A hydrogen conductivity measurement system and method

Abstract

This invention discloses a hydrogen conductivity measurement system and method. The outlet of an ultrapure water tank is connected to one end of an ultrapure water pump and one end of an inlet valve. The other end of the inlet valve is connected to the inlet of a mixer via a degassing device. The water sample input pipeline is connected to the inlet of the mixer via an injection valve. The outlet of the mixer is connected to the inlet of a thermostat. The outlet of the thermostat is connected to the inlet of a hydrogen-type cation exchange column. The outlet of the hydrogen-type cation exchange column is connected to the inlet of a hydrogen conductivity electrode. The outlet of the hydrogen conductivity electrode is connected to the inlet of a pH electrode. The hydrogen conductivity electrode is connected to a hydrogen conductivity transmitter, and the pH electrode is connected to a pH transmitter. A first flow meter is installed at the outlet of the degassing device, and a second flow meter is installed at the outlet of the injection valve. This system and method can increase the service life of the cation exchange resin while ensuring accurate hydrogen conductivity measurement.

Description

Technical Field

[0001] This invention belongs to the field of water quality monitoring technology and relates to a hydrogen conductivity measurement system and method. Background Technology

[0002] Hydrogen conductivity is one of the important indicators for monitoring the quality of steam and water in thermal power plants and for chemical surveillance. Hydrogen conductivity is measured after the water sample has been passed through a cation exchange resin to replace cations with hydrogen ions; it reflects the overall level of anions in the water.

[0003] In power plant thermal systems, ammonia is commonly added to feedwater to prevent metal corrosion, with ammonia levels typically ranging from 1 to 3 mg / L. During hydrogen conductivity measurements, the active groups of the cation exchange resin are largely consumed by ammonium ions. When the resin becomes ineffective, it must be replaced, which creates a measurement vacuum period, negatively impacting chemical monitoring and control. Furthermore, frequent resin replacements increase the workload for on-site personnel.

[0004] For some water samples, such as those from heating return water, gas turbine units, and small-capacity, low-parameter boiler drums, the conductivity is relatively high. When measuring hydrogen conductivity, the cation exchange resin fails quickly, which greatly limits the measurement of hydrogen conductivity in these water samples. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a hydrogen conductivity measurement system and method that can increase the service life of cation exchange resin while ensuring accurate hydrogen conductivity measurement.

[0006] To achieve the above objectives, the hydrogen conductivity measurement system of the present invention includes an ultrapure water tank, an ultrapure water pump, an inlet valve, a degassing device, a mixer, a water sample input pipeline, an injection valve, a constant temperature device, a hydrogen-type cation exchange column, a hydrogen conductivity electrode, a pH electrode, a hydrogen conductivity transmitter, a pH transmitter, and a signal processing system.

[0007] The outlet of the ultrapure water tank is connected to one end of the ultrapure water pump and one end of the inlet valve. The other end of the inlet valve is connected to the inlet of the mixer via the degassing device. The water sample input pipeline is connected to the inlet of the mixer via the injection valve. The outlet of the mixer is connected to the inlet of the thermostat. The outlet of the thermostat is connected to the inlet of the hydrogen-type cation exchange column. The outlet of the hydrogen-type cation exchange column is connected to the inlet of the hydrogen conductivity electrode. The outlet of the hydrogen conductivity electrode is connected to the inlet of the pH electrode. The hydrogen conductivity electrode is connected to the hydrogen conductivity transmitter, and the pH electrode is connected to the pH transmitter.

[0008] A first flow meter is installed at the outlet of the degassing device, and a second flow meter is installed at the outlet of the injection valve. The first flow meter, the second flow meter, the pH transmitter, and the hydrogen conductivity transmitter are connected to the signal processing system.

[0009] One end of the reflux valve is connected to the outlet of the ultrapure water pump, and the other end of the reflux valve is connected to the ultrapure water tank.

[0010] The outlet of the pH electrode is connected to the trench.

[0011] The hydrogen conductivity electrode is connected to the hydrogen conductivity transmitter via the first signal line.

[0012] The pH electrode is connected to the pH transmitter via a second signal line.

[0013] The signal processing system is connected to a display screen.

[0014] The hydrogen-form cation exchange column is filled with hydrogen-form cation exchange resin.

[0015] The hydrogen conductivity measurement method of the present invention includes the following steps:

[0016] Obtain the flow rate information of the water at the outlet of the degassing device as measured by the first flow meter;

[0017] Obtain the flow rate information of the water at the outlet of the sampling valve measured by the second flow meter;

[0018] Obtain the pH value of the water at the outlet of the hydrogen-type cation exchange column output by the pH transmitter;

[0019] Obtain the hydrogen conductivity information of the water at the outlet of the hydrogen-type cation exchange column output by the hydrogen conductivity transmitter;

[0020] The hydrogen conductivity (CC) of the water sample to be tested was calculated based on the obtained flow rate information of the water at the outlet of the degassing device, the flow rate information of the water at the outlet of the injection valve, the pH value of the water at the outlet of the hydrogen-type cation exchange column, and the hydrogen conductivity information of the water at the outlet of the hydrogen-type cation exchange column.

[0021] The hydrogen conductivity CC of the water sample to be tested is:

[0022]

[0023] Among them, Q 纯水 This refers to the flow rate of water at the outlet of the degassing device measured by the first flow meter; Q 水样 This refers to the flow rate information of the water at the outlet of the sampling valve measured by the second flow meter; CC 测 The hydrogen conductivity information is output by the hydrogen conductivity transmitter as the water at the outlet of the hydrogen-type cation exchange column; pH is output by the pH transmitter as the pH value of the water at the outlet of the hydrogen-type cation exchange column. The limiting molar conductivity for hydrogen ions. is the limiting molar conductivity of hydroxide ions.

[0024] The present invention has the following beneficial effects:

[0025] In practical operation, the hydrogen conductivity measurement system and method described in this invention, while keeping the total flow rate of the hydrogen conductivity meter constant, reduces the amount of impurity cations in the water sample passing through the cation exchange resin by diluting it with ultrapure water. This significantly extends the service life of the ion exchange resin to k times its original value. The hydrogen conductivity of the water sample to be tested is then calculated using a formula, ensuring measurement accuracy and effectively solving the problem of frequent resin replacement. This makes it possible to continuously measure the hydrogen conductivity of high-conductivity water samples over a long period of time. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the present invention.

[0027] Among them, 1 is an ultrapure water tank, 2 is an ultrapure water pump, 3 is a reflux valve, 4 is an inlet valve, 5 is a degassing device, 6 is a first flow meter, 7 is an injection valve, 8 is a second flow meter, 9 is a mixer, 10 is a constant temperature device, 11 is a hydrogen-type cation exchange column, 12 is a hydrogen conductivity electrode, 13 is a hydrogen conductivity transmitter, 14 is a pH electrode, 15 is a pH transmitter, and 16 is a signal processing system. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, not all embodiments, and are not intended to limit the scope of the present invention. Furthermore, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion regarding the concepts disclosed in the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort should fall within the scope of protection of the present invention.

[0029] The accompanying drawings show structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not drawn to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0030] refer to Figure 1The hydrogen conductivity measurement system of the present invention includes an ultrapure water tank 1, an ultrapure water pump 2, a reflux valve 3, an inlet valve 4, a degassing device 5, a first flow meter 6, an injection valve 7, a second flow meter 8, a mixer 9, a constant temperature device 10, a hydrogen-type cation exchange column 11, a hydrogen conductivity electrode 12, a hydrogen conductivity transmitter 13, a pH electrode 14, a pH transmitter 15, and a signal processing system 16.

[0031] The outlet of the ultrapure water tank 1 is connected to one end of the reflux valve 3 and one end of the inlet valve 4 via the ultrapure water pump 2. The other end of the reflux valve 3 is connected to the ultrapure water tank 1. The other end of the inlet valve 4 is connected to the inlet of the mixer 9 via the degassing device 5. The water sample input pipeline is connected to the inlet of the mixer 9 via the injection valve 7. The outlet of the mixer 9 is connected to the inlet of the thermostat 10. The outlet of the thermostat 10 is connected to the inlet of the hydrogen-type cation exchange column 11. The outlet of the hydrogen-type cation exchange column 11 is connected to the inlet of the hydrogen conductivity electrode 12. The outlet of the hydrogen conductivity electrode 12 is connected to the inlet of the pH electrode 14. The outlet of the pH electrode 14 is connected to the drain. The hydrogen conductivity electrode 12 is connected to the hydrogen conductivity transmitter 13. The pH electrode 14 is connected to the pH transmitter 15.

[0032] Specifically, the hydrogen conductivity electrode 12 is connected to the hydrogen conductivity transmitter 13 via a first signal line, and the pH electrode 14 is connected to the pH transmitter 15 via a second signal line.

[0033] A first flow meter 6 is installed at the outlet of the degassing device 5, and a second flow meter 8 is installed at the outlet of the injection valve 7. The first flow meter 6, the second flow meter 8, the pH transmitter 15, and the hydrogen conductivity transmitter 13 are connected to the signal processing system 16.

[0034] The signal processing system 16 is connected to a display screen to display the hydrogen conductivity value of the water sample to be tested.

[0035] The conductivity of ultrapure water after removing gases such as carbon dioxide by degassing device 5 is 0.055 μS / cm (25℃). Degassing device 5 uses degassing membrane method, nitrogen stripping method or boiling method for degassing.

[0036] The constant temperature device 10 uses a water bath or other methods to maintain the water temperature at around 25°C.

[0037] The hydrogen-form cation exchange column 11 is filled with hydrogen-form cation exchange resin.

[0038] The solution diluted to remove impurity cations is considered an infinitely diluted solution, and its hydrogen conductivity is:

[0039]

[0040] Where CC is the hydrogen conductivity, μS / cm; [H+ [ ] represents the hydrogen ion concentration, in mol / L; The limiting molar conductivity for hydrogen ions is given in μS·cm. 2 / mol; [OH - [ ] represents the hydroxide ion concentration, in mol / L; The limiting molar conductivity of hydroxide ions is given in μS·cm. 2 / mol; [M] is the concentration of anion M, mol / L; The limiting molar conductivity of the anion M is given in μS·cm. 2 / mol;

[0041] The signal processing system 16 receives the flow rate Q measured by the first flow meter 6. 纯水 The flow rate Q measured by the second flow meter 8 水样 The measured value CC of hydrogen conductivity transmitter 13 测 The pH value measured by pH transmitter 15 is used to calculate the dilution factor.

[0042] The concentration of hydrogen ions in the water sample after passing through hydrogen-type cation exchange column 11 [H] + ] 测 =10 -pH The concentration of hydroxide ions [OH] - ] 测 =10 pH-14 Among them, the hydrolysis constant K of water at 25℃ w =10 -14 Based on the cation-anion balance, the concentration of impurity anions ∑[M] 测 for:

[0043] ∑[M] 测 =[H + ] 测 -[OH - ] 测 =10 -pH -10 pH-14

[0044] The concentration of impurity anions in the water sample after passing through hydrogen cation exchange column 11 for:

[0045]

[0046] The concentration of impurity anions in the water sample to be tested, ∑[M], is:

[0047]

[0048] Hydrogen ion concentration [H] in the water sample to be tested + ]for:

[0049]

[0050] The concentration of hydroxide ions in the water sample to be tested [OH] - ]for:

[0051]

[0052] Concentration of impurity anions in the water sample to be tested for:

[0053]

[0054] Substituting into the formula for calculating hydrogen conductivity, we get...

[0055]

[0056] Where CC is the hydrogen conductivity of the water sample to be tested; Q 纯水 The reading for the first flow meter 6; Q 水样 For the reading of the second flow meter 8; CC 测 The value is the hydrogen conductivity transmitter 13; the pH value is the pH transmitter 15. The limiting molar conductivity for hydrogen ions. is the limiting molar conductivity of hydroxide ions.

[0057] Based on the above theory, the hydrogen conductivity measurement method of the present invention includes the following steps:

[0058] Obtain the flow rate information of the water at the outlet of the degassing device 5 measured by the first flow meter 6;

[0059] Obtain the flow rate information of the water at the outlet of the sampling valve 7 measured by the second flow meter 8;

[0060] Obtain the pH value of the water at the outlet of the hydrogen-type cation exchange column 11 output by pH transmitter 15;

[0061] Obtain the hydrogen conductivity information of the water at the outlet of the hydrogen-type cation exchange column 11 output by the hydrogen conductivity transmitter 13;

[0062] The hydrogen conductivity (CC) of the water sample to be tested was calculated based on the obtained flow rate information of the water at the outlet of the degassing device 5, the flow rate information of the water at the outlet of the injection valve 7, the pH value of the water at the outlet of the hydrogen-type cation exchange column 11, and the hydrogen conductivity information of the water at the outlet of the hydrogen-type cation exchange column 11.

[0063] It should be noted that, while maintaining the total flow rate of the hydrogen conductivity meter, this invention reduces the amount of impurity cations in the water sample passing through the cation exchange resin by diluting it with ultrapure water. This significantly extends the service life of the ion exchange resin, increasing it to k times the original value. The hydrogen conductivity of the water sample to be tested is obtained by calculation formula to ensure the accuracy of the measurement, effectively solve the problem of frequent resin replacement, and make it possible to continuously measure the hydrogen conductivity of high conductivity water samples for a long time.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A hydrogen conductivity measurement system, characterized in that, It includes an ultrapure water tank (1), an ultrapure water pump (2), an inlet valve (4), a degassing device (5), a mixer (9), a water sample input pipeline, an inlet valve (7), a constant temperature device (10), a hydrogen-type cation exchange column (11), a hydrogen conductivity electrode (12), a pH electrode (14), a hydrogen conductivity transmitter (13), a pH transmitter (15), and a signal processing system (16). The outlet of the ultrapure water tank (1) is connected to one end of the inlet valve (4) via the ultrapure water pump (2), and the other end of the inlet valve (4) is connected to the inlet of the mixer (9) via the degassing device (5). The water sample input pipeline is connected to the inlet of the mixer (9) via the injection valve (7). The outlet of the mixer (9) is connected to the inlet of the thermostat (10). The outlet of the thermostat (10) is connected to the inlet of the hydrogen-type cation exchange column (11). The outlet of the hydrogen-type cation exchange column (11) is connected to the inlet of the hydrogen conductivity electrode (12). The outlet of the hydrogen conductivity electrode (12) is connected to the inlet of the pH electrode (14). The hydrogen conductivity electrode (12) is connected to the hydrogen conductivity transmitter (13), and the pH electrode (14) is connected to the pH transmitter (15). A first flow meter (6) is installed at the outlet of the degassing device (5), and a second flow meter (8) is installed at the outlet of the injection valve (7). The first flow meter (6), the second flow meter (8), the pH transmitter (15) and the hydrogen conductivity transmitter (13) are connected to the signal processing system (16).

2. The hydrogen conductivity measurement system according to claim 1, characterized in that, One end of the reflux valve (3) is connected to the outlet of the ultrapure water pump (2), and the other end of the reflux valve (3) is connected to the ultrapure water tank (1).

3. The hydrogen conductivity measurement system according to claim 1, characterized in that, The outlet of the pH electrode (14) is connected to the trench.

4. The hydrogen conductivity measurement system according to claim 1, characterized in that, The hydrogen conductivity electrode (12) is connected to the hydrogen conductivity transmitter (13) via the first signal line.

5. The hydrogen conductivity measurement system according to claim 1, characterized in that, The pH electrode (14) is connected to the pH transmitter (15) via a second signal line.

6. The hydrogen conductivity measurement system according to claim 1, characterized in that, The signal processing system (16) is connected to a display screen.

7. The hydrogen conductivity measurement system according to claim 1, characterized in that, The hydrogen-form cation exchange column (11) is filled with hydrogen-form cation exchange resin.

8. A method for measuring hydrogen conductivity, characterized in that, The hydrogen conductivity measurement system according to claim 1 includes the following steps: Obtain the flow rate information of the water at the outlet of the degassing device (5) measured by the first flow meter (6); Obtain the flow rate information of the water at the outlet of the sampling valve (7) measured by the second flow meter (8); Obtain the pH value of the water at the outlet of the hydrogen-type cation exchange column (11) output by the pH transmitter (15); Obtain the hydrogen conductivity information of the water at the outlet of the hydrogen-type cation exchange column (11) output by the hydrogen conductivity transmitter (13); The hydrogen conductivity of the water sample to be tested is calculated based on the obtained flow rate information of the water at the outlet of the degassing device (5), the flow rate information of the water at the outlet of the injection valve (7), the pH value of the water at the outlet of the hydrogen-type cation exchange column (11), and the hydrogen conductivity information of the water at the outlet of the hydrogen-type cation exchange column (11). .

9. The method for measuring hydrogen conductivity according to claim 8, characterized in that, Hydrogen conductivity of the water sample to be tested for: in, The flow rate information of the water at the outlet of the degassing device (5) measured by the first flow meter (6); The flow rate information of the water at the outlet of the sampling valve (7) measured by the second flow meter (8); The hydrogen conductivity information of the water at the outlet of the hydrogen-type cation exchange column (11) is output by the hydrogen conductivity transmitter (13); pH is the pH value of the water at the outlet of the hydrogen-type cation exchange column (11) is output by the pH transmitter (15). The limiting molar conductivity of hydrogen ions; is the limiting molar conductivity of hydroxide ions.

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