Method for improving calcium carbonate content in precipitate produced by electrolysis of water

Abstract

The present application relates to a method for improving the content of calcium carbonate in electrolytic water precipitate, taking calcium hardness, magnesium hardness and alkalinity as independent variables, obtaining the regression model of calcium hardness, magnesium hardness and alkalinity and the regression model of gas-water ratio under the condition of non-aeration improvement, calculating the gas-water ratio, realizing the application of electrolytic water precipitate in limestone wet flue gas desulfurization, improving the reaction rate of electrolytic water precipitation process and the content of calcium carbonate in electrolytic water precipitate to more than 95%, realizing the application of electrolytic water precipitate in limestone wet flue gas desulfurization, directly calculating the working condition of aeration improvement according to the quality of cooling water, avoiding blind test and saving labor cost; the water quality index of enterprise cooling water can be directly applied in this range, and the regression equation can be determined again according to the test method if it is not in this range, which has strong applicability.

Description

Technical Field

[0001] This invention relates to the field of water electrolysis, and in particular to a method for increasing the calcium carbonate content in the precipitate generated by water electrolysis. Background Technology

[0002] Electrolysis of water is a water treatment method with many advantages, including environmental friendliness, simple equipment for easy automation, and strong adaptability. It is a green water treatment technology with broad application prospects. In the electrolysis process, cooling water contains Ca... 2+ Mg 2 + and HCO3 - When scale-forming ions are transferred to the high pH region, a chemical precipitation reaction occurs, generating precipitates that crystallize and grow on the cathode surface, forming a precipitate layer.

[0003] Cooling water is a major category of industrial water use, accounting for over 70% of total water consumption in enterprises. Applying the calcium carbonate generated during cooling water treatment to desulfurization facilities in large-scale industries such as coal-fired power plants would generate significant economic and social benefits. However, the calcium carbonate content of the precipitate generated from water electrolysis is low (<70%), making it unsuitable for flue gas desulfurization (limestone wet flue gas desulfurization requires a CaCO3 purity greater than 85%). Currently, there is no method to increase the calcium carbonate content in the precipitate generated from water electrolysis.

[0004] Therefore, there is an urgent need for a method to increase the calcium carbonate content in the precipitate generated by water electrolysis. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method for increasing the calcium carbonate content in the precipitate generated by water electrolysis, significantly improving the calcium carbonate content in the precipitate generated by cooling water treatment, and enabling its application in limestone wet flue gas desulfurization in coal-fired power plants.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A method for increasing the calcium carbonate content in precipitates generated by water electrolysis includes the following steps:

[0008] (1) Determine the range of calcium hardness, magnesium hardness, and alkalinity of the cooling water based on the enterprise's cooling water quality report;

[0009] (2) Experimental design and data processing

[0010] Using calcium hardness, magnesium hardness and alkalinity as independent variables, and calcium hardness precipitation rate and magnesium hardness precipitation rate as response values, at least 20 sets of experiments were designed based on a second-order universal rotational combination, of which 15 sets were factorial test points and 5 sets were repeating central test points, and the order of the test points in each set was randomly arranged.

[0011] The above experimental results were subjected to regression analysis to obtain regression models of calcium hardness, magnesium hardness, and alkalinity with the proportion of calcium carbonate content during the electrolytic water precipitation process under non-aeration conditions. The significance of these models was verified and the regression model of P was determined.

[0012] (3) Set the target value of calcium carbonate content to 95%, determine the ratio of aeration flow rate to influent flow rate, i.e., the air-to-water ratio, and under no aeration conditions, the difference between the calcium carbonate content and 95% is P. 差 (%)

[0013] P 差 =95-P

[0014] Regression analysis was performed on the experimental results to obtain the difference P between calcium hardness, magnesium hardness, alkalinity, and calcium carbonate content under aeration conditions. 差 The regression model of the air-water ratio GF is determined by the ratio of (%) to the aeration flow rate to the influent flow rate, and the regression model of GF is determined after verifying its significance.

[0015] (4) Obtain the calcium hardness, magnesium hardness and alkalinity of the cooling water to be electrolyzed, and substitute them into the regression model of P to obtain the percentage of calcium carbonate in the precipitate of electrolyzed water under the condition of no aeration.

[0016] (5) Calculate the difference between the percentage of calcium carbonate content P (%) and 95% as P. 差 (%), calcium hardness, magnesium hardness, alkalinity, P 差 Substituting the values ​​into the regression model of GF, we obtain the air-to-water ratio GF under the condition of enhanced aeration.

[0017] (6) During the electrolytic water precipitation process, the ratio of gas flow rate to influent flow rate is increased to the GF value obtained in step (5), thereby increasing the calcium carbonate content to the target value (close to or exceeding 95%), so as to realize the application of electrolytic water precipitate in limestone wet flue gas desulfurization.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] (1) While increasing the reaction rate of the electrolytic water precipitation process, the calcium carbonate content in the electrolytic water precipitate is increased to more than 95%, so as to realize the application of electrolytic water precipitate in limestone wet flue gas desulfurization.

[0020] (2) High efficiency: The working conditions for aeration enhancement can be directly calculated based on the cooling water quality, avoiding blind experimentation and saving manpower costs.

[0021] (3) Wide applicability: Water quality indicators of enterprise cooling water within this range can be directly applied, while those outside this range can have their regression equations re-determined based on experimental methods, making it highly applicable. Detailed Implementation

[0022] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, working principle and examples.

[0023] The working principle of this invention is as follows:

[0024] Cooling water contains Ca 2+ Mg 2+ Fe 2+ Cu 2+ These cations, during water electrolysis, will react with the OH groups produced by the reduction reaction of water electrolysis. - The reaction directly produces a precipitate, except for Ca. 2+ Other cations can cause a decrease in the CaCO3 content of the precipitate. This is due to the presence of Fe in the cooling water. 2+ Cu 2+ Since the concentration of cations is relatively low, the CaCO3 content in the precipitate is mainly increased by reducing the content of MgCO3 and Mg(OH)2 in the precipitate.

[0025] According to Ca 2+ and Mg 2+ Precipitation kinetics study, Ca 2+ and Mg 2+ The fitting formulas for the precipitation rate constants are as follows:

[0026]

[0027]

[0028] In the formula, For Ca 2+ The precipitation rate constant;

[0029] For Ca in solution 2+ molar concentration, mmol·L -1 ;

[0030] k I→∞ When the current density approaches infinity, Ca 2+ The limiting precipitation rate constant;

[0031] I is the current density, A·m -2 ;

[0032] k Mg2+ Mg 2+ The precipitation rate constant;

[0033] C Mg2+ Mg in solution 2+ molar concentration, mmol·L-1 .

[0034] From formula (1), we can see that Ca 2+ The precipitation rate constant is related to the Ca in the solution. 2+ When the molar concentration, current density, and current density approach infinity, Ca 2+ The limiting precipitation rate constant is related to the influent aqueous solution; when the influent aqueous solution is constant, Ca 2+ The precipitation rate constant is mainly related to the current density, and the precipitation rate constant of Ca approaches infinity. 2+ It is related to the limiting precipitation rate constant.

[0035] From formula (2), we can see that Mg 2+ The precipitation rate constant is related to the amount of Mg in the solution. 2+ The molar concentration and current density are related; when the influent aqueous solution is constant, Mg 2+ The precipitation rate constant is mainly related to the current density.

[0036] Furthermore, as the current density approaches infinity, Ca... 2+ The limiting precipitation rate constant, and Ca 2+ HCO3 - The mass transfer rate is related to the current density, i.e., Ca 2+ HCO3 - The higher the mass transfer rate, the larger the limiting sedimentation rate constant, and consequently, the greater the Ca... 2+ The larger the precipitation rate constant, the greater the precipitation rate constant.

[0037] Comparing formulas (1) and (2), the change in mass transfer rate does not affect Mg. 2+ The precipitation rate of Ca can be adjusted by increasing the mass transfer rate. 2+ The precipitation rate constant of Mg 2+ The ratio of the precipitation rate constant to the precipitation rate constant of Ca increases the efficiency of the water electrolysis precipitation process. 2+ The selective removal process increases the calcium carbonate content during water electrolysis precipitation.

[0038] Common methods to accelerate ion mass transfer include mechanical stirring, aeration, and ultrasound. Considering the space constraints between electrode plates and equipment investment, aeration is chosen to accelerate ion convection mass transfer. This method does not require redesigning or modifying the existing water electrolysis equipment; simply adding aeration devices in suitable locations will achieve the desired effect.

[0039] Therefore, the water electrolysis precipitation process affects Ca 2+ The selectivity of removal is mainly affected by three factors: first, the ratio of aeration flow rate to influent flow rate, i.e., the air-to-water ratio; second, the amount of Ca in the influent solution; and third, the concentration of Ca in the influent solution. 2+ molar concentration of Mg 2+The ratio of molar concentrations, and the third is the alkalinity of the influent solution, in mmol / L.

[0040] Increasing the gas-to-water ratio can improve the mass transfer rate of ions, but it can also increase the washing and friction effect of bubbles on the precipitates attached to the cathode surface, hindering the rapid accumulation of precipitates and thus affecting the collection of precipitates on the electrode plate.

[0041] According to a survey of the company's cooling water quality report, the influent solution contains Ca... 2+ The molar concentration of Mg is generally between 2 and 5 mmol / L. 2+ The molar concentration is generally between 1.0 and 3.0 mmol / L, and the alkalinity is generally between 4 and 8 mmol / L.

[0042] Experimental design and data processing were performed using mathematical software, with calcium hardness, magnesium hardness, and alkalinity as three independent variables, among which calcium hardness (mmol·L⁻¹) was used. -1 The value is A, and the magnesium hardness (mmol·L) -1 The value is B, and the alkalinity (mmol·L) -1 Let C be the calcium hardness precipitation rate and magnesium hardness precipitation rate, and then calculate the percentage of calcium carbonate content (%) P.

[0043] Calcium hardness precipitation rate (V) Ca2+ () represents the mass of calcium hardness removed per unit time per unit cathode plate, expressed as CaCO3, in g·m³. -2 ·h -1 The calculation formula is as follows:

[0044]

[0045] In the formula, Q is the influent flow rate, L·min -1 ; and Calcium hardness of influent and effluent, respectively, in mmol·L⁻¹ -1 A is the effective cathode plate area, in meters. 2 .

[0046] Magnesium hardness precipitation rate It represents the mass of magnesium hardness removed per unit time per unit cathode plate, expressed as CaCO3, with units of g·m. -2 ·h -1 The calculation formula is as follows:

[0047]

[0048] In the formula, Q is the influent flow rate, L·min -1 ; and Magnesium hardness of influent and effluent, respectively, in mmol·L⁻¹ -1 A is the effective cathode plate area, in meters. 2 .

[0049] The formula for calculating the percentage (%) of calcium carbonate (P) is as follows:

[0050]

[0051] The design factors and levels under the condition of no aeration enhancement are shown in Table 1.

[0052] Table 1. Experimental Design Factors and Levels (No Aeration Increase)

[0053]

[0054] A total of 20 experiments were designed, including 15 factorial experimental sites and 5 repeating central experimental sites. The order of the experimental sites in each group was randomized. The repeating experiments at the central sites were used to estimate the error of the experimental design. The codes and levels of the independent variables under the condition of no aeration enhancement are shown in Table 2.

[0055] Table 2. Codes and levels of independent variables in the experiment (without aeration improvement)

[0056]

[0057]

[0058] The test results under conditions without aeration enhancement are shown in Table 3.

[0059] Table 3. Experimental Results (No Aeration Increase)

[0060]

[0061]

[0062] Regression analysis was performed on the above experimental results to obtain regression models for calcium hardness, magnesium hardness, and alkalinity in relation to the proportion of calcium carbonate content during the electrolytic water precipitation process under conditions without aeration enhancement.

[0063] P=109.407+13.636A-17.095B-22.13C-20.582AB+2.729AC+16.459BC+6.316AB 2

[0064] -2.58B 2 C-1.062ABC-0.068A 3 -1.063B 3 -0.012C 3

[0065] The model test table, analysis of variance table, and coefficient test table for the regression equation are shown in Tables 4, 5, and 6, respectively.

[0066] Table 4. Regression Equation Model Test Table

[0067] Model R <![CDATA[R 2 ]]> <![CDATA[Standard R 2 > Standard error of the estimate The regression equation of P 0.963 0.928 0.805 3.310

[0068] Table 5. Analysis of Variance Table for Regression Equations

[0069]

[0070] Table 6. Test Table for Regression Equation Coefficients

[0071]

[0072]

[0073] As shown in Tables 4, 5, and 6, the regression model of P is significant.

[0074] Based on the precipitation process of water electrolysis, Ca 2+ To determine the selectivity of calcium carbonate removal, the aeration conditions were adjusted to increase the proportion of calcium carbonate content. A target value of 95% was set (this target value of 95% is an empirical value; it ensures that the calcium carbonate content meets the flue gas desulfurization requirements while avoiding an excessively high air-to-water ratio that could affect the collection of sediment on the electrode plates). The ratio of aeration flow rate to influent flow rate, i.e., the air-to-water ratio, was determined. Under conditions without aeration enhancement, the difference between the calcium carbonate content proportion and 95% is P. 差 (%).

[0075] P 差 =95-P

[0076] The test results are shown in Table 7.

[0077] Table 7. Results of the air-to-water ratio experiment under enhanced aeration conditions, increasing the calcium carbonate content to 95%.

[0078]

[0079]

[0080] Regression analysis was performed on the above experimental results to obtain the difference P between calcium hardness (A), magnesium hardness (B), alkalinity (C), and calcium carbonate content percentage under aeration conditions. 差 The regression model of the air-to-water ratio (GF) is the ratio of aeration flow rate to influent flow rate.

[0081] GF=-12.295+4.263A+2.351C+0.264P 差 -0.21AC -0.026AP 差

[0082] +0.286BC - 0.279A 2 -0.523B 2 -0.168C 2 -0.003P 差 2

[0083] The model test table, analysis of variance table, and coefficient test table for the regression equation are shown in Tables 8, 9, and 10, respectively.

[0084] Table 8. Regression Equation Model Test Table

[0085] Model R <![CDATA[R 2 ]]> <![CDATA[Standard R 2 > Standard error of the estimate GF regression equation 0.996 0.992 0.984 0.146

[0086] Table 9. Analysis of Variance Table for Regression Equations

[0087]

[0088] Table 10: Test Table for Regression Equation Coefficients

[0089]

[0090] As shown in Tables 8, 9 and 10, the regression model of GF is significant.

[0091] By using the regression models of P and GF, the ratio of gas flow rate to influent flow rate, i.e., the gas-water ratio, is calculated under given conditions, thereby increasing the calcium carbonate content to 95% and enabling the application of electrolyzed water precipitate in limestone wet flue gas desulfurization.

[0092] Based on this, a method for increasing the calcium carbonate content in the precipitate generated by water electrolysis is obtained, comprising the following steps:

[0093] (1) Obtain the cooling water quality, including calcium hardness (A), magnesium hardness (B), and alkalinity (C), and substitute them into the regression equation for P to calculate the P value:

[0094] P=109.407+13.636A-17.095B-22.13C-20.582AB+2.729AC+16.459BC+6.316AB 2

[0095] -2.58B 2 C-1.062ABC-0.068A 3 -1.063B 3 -0.012C 3

[0096] Under conditions of no aeration enhancement, the percentage of calcium carbonate in the precipitate of electrolyzed water was obtained (P).

[0097] (2) Calculate the difference between the percentage of calcium carbonate and 95% under the condition of no aeration enhancement, and the value of P. 差 :

[0098] P 差 =95-P

[0099] P 差 Substitute into the regression model of GF:

[0100] GF=-12.295+4.263A+2.351C+0.264P 差 -0.21AC -0.026AP 差

[0101] +0.286BC - 0.279A 2 -0.523B 2 -0.168C 2 -0.003P 差 2

[0102] Under conditions of enhanced aeration, the air-to-water ratio GF;

[0103] (3) During the electrolysis precipitation process, the ratio of gas flow rate to influent flow rate is increased to the GF value, thereby increasing the calcium carbonate content to the target value (close to or exceeding 95%), so as to realize the application of electrolysis water precipitate in limestone wet flue gas desulfurization.

[0104] The embodiments of the present invention are as follows:

[0105] Example 1

[0106] A thermal power plant uses electrolytic water treatment in its cooling water system. The calcium hardness of the cooling water is 4.2 mmol·L⁻¹. -1 The magnesium hardness is 2.5 mmol·L. -1 The alkalinity is 5.1 mmol·L. -1 The experiment showed that the calcium carbonate content during the water electrolysis precipitation process was 67.9%, which is lower than the purity requirement of CaCO3 (85%) for limestone wet flue gas desulfurization. Therefore, the water electrolysis precipitate cannot be used in flue gas desulfurization.

[0107] Using the method of this invention:

[0108] Calculate the P-value based on the regression equation (regression model) of cooling water quality and P.

[0109] A = 4.2 mmol·L -1 B = 2.5 mmol·L -1 C = 5.1 mmol·L -1

[0110] Substitute into the regression equation of P

[0111] P=109.407+13.636A-17.095B-22.13C-20.582AB+2.729AC+16.459BC+6.316AB 2

[0112] -2.58B 2 C-1.062ABC-0.068A 3 -1.063B 3 -0.012C 3

[0113] Under conditions without aeration, the calcium carbonate content (P%) was 66.7%.

[0114] Under conditions of no aeration enhancement, the difference between the percentage of calcium carbonate and 95% is P. 差 (%)

[0115] P 差 =95-P

[0116] Get P 差 (%) = 28.3%

[0117] Substitute into the regression model of GF:

[0118] GF=-12.295+4.263A+2.351C+0.264P 差 -0.21AC -0.026AP 差

[0119] +0.286BC - 0.279A 2 -0.523B 2 -0.168C 2 -0.003P 差 2

[0120] With GF = 6.2, the air-to-water ratio is determined to be 6.2 under the condition of enhanced aeration.

[0121] The experiment showed that, under the condition of a gas-to-water ratio of 6.2, the calcium carbonate content during the electrolytic water precipitation process increased to 94.6%, which is higher than the purity requirement of CaCO3 (85%) for limestone wet flue gas desulfurization. The electrolytic water precipitate has been successfully applied in flue gas desulfurization.

[0122] Example 2

[0123] A thermal power plant uses electrolytic water treatment in its cooling water system. The calcium hardness of the cooling water is 2.9 mmol·L⁻¹. -1 The magnesium hardness is 2.2 mmol·L⁻¹. -1The alkalinity is 4.6 mmol·L. -1 The experiment showed that the calcium carbonate content during the water electrolysis precipitation process was 66.2%, which is lower than the purity requirement of CaCO3 (85%) for limestone wet flue gas desulfurization. Therefore, the water electrolysis precipitate cannot be used in flue gas desulfurization.

[0124] Using the method of this invention:

[0125] Calculate the P value based on the regression equation of cooling water quality and P:

[0126] A = 2.9 mmol·L -1 B = 2.2 mmol·L -1 C = 4.6 mmol·L -1

[0127] Substitute P into the regression model:

[0128] P=109.407+13.636A-17.095B-22.13C-20.582AB+2.729AC+16.459BC+6.316AB 2

[0129] -2.58B 2 C-1.062ABC-0.068A 3 -1.063B 3 -0.012C 3

[0130] Under conditions without aeration, the calcium carbonate content (P%) was 67.1%.

[0131] Under conditions of no aeration enhancement, the difference between the percentage of calcium carbonate and 95% is P. 差 (%)

[0132] P 差 =95-P

[0133] Get P 差 (%) = 27.9%

[0134] Substitute into the regression model of GF:

[0135] GF=-12.295+4.263A+2.351C+0.264P 差 -0.21AC -0.026AP 差

[0136] +0.286BC - 0.279A 2 -0.523B 2 -0.168C 2 -0.003P差 2

[0137] With GF = 5.5, the air-to-water ratio is determined to be 5.5 under the condition of enhanced aeration.

[0138] Experiments showed that, under a gas-to-water ratio of 5.5, the calcium carbonate content during the water electrolysis precipitation process increased to 95.2%, which is higher than the purity requirement of CaCO3 (85%) for limestone wet flue gas desulfurization. The water electrolysis precipitate has been successfully applied in flue gas desulfurization.

[0139] Example 3

[0140] A thermal power plant uses electrolytic water treatment in its cooling water system. The calcium hardness of the cooling water is 4.7 mmol·L⁻¹. -1 The magnesium hardness is 1.9 mmol·L. -1 The alkalinity is 4.1 mmol·L. -1 The experiment showed that the calcium carbonate content during the water electrolysis precipitation process was 63.2%, which is lower than the purity requirement of CaCO3 (85%) for limestone wet flue gas desulfurization. Therefore, the water electrolysis precipitate cannot be used in flue gas desulfurization.

[0141] Using the method of this invention:

[0142] Calculate the P value based on the regression equation of cooling water quality and P:

[0143] A = 4.7 mmol·L -1 B = 1.9 mmol·L -1 C = 4.1 mmol·L -1

[0144] Substitute P into the regression equation:

[0145] P=109.407+13.636A-17.095B-22.13C-20.582AB+2.729AC+16.459BC+6.316AB 2

[0146] -2.58B 2 C-1.062ABC-0.068A 3 -1.063B 3 -0.012C 3

[0147] Under conditions without aeration, the calcium carbonate content (P%) was 62.2%.

[0148] Under conditions of no aeration enhancement, the difference between the percentage of calcium carbonate and 95% is P. 差 (%).

[0149] P 差 =95-P

[0150] Get P 差 (%) = 32.8%

[0151] Substitute into the regression model of GF:

[0152] GF=-12.295+4.263A+2.351C+0.264P 差 -0.21AC -0.026AP 差

[0153] +0.286BC - 0.279A 2 -0.523B 2 -0.168C 2 -0.003P 差 2

[0154] With GF = 6.1, the air-to-water ratio is determined to be 6.1 under the condition of enhanced aeration.

[0155] The experiment showed that, under the condition of a gas-to-water ratio of 6.1, the calcium carbonate content during the electrolytic water precipitation process increased to 94.8%, which is higher than the purity requirement of CaCO3 (85%) for limestone wet flue gas desulfurization. The electrolytic water precipitate has been successfully applied in flue gas desulfurization.

Claims

1. A method for increasing the calcium carbonate content in precipitates generated by water electrolysis, characterized in that, Includes the following steps: (1) Determine the range of calcium hardness, magnesium hardness, and alkalinity of the cooling water based on the enterprise's cooling water quality report; (2) Experimental design and data processing Using calcium hardness, magnesium hardness and alkalinity as independent variables, and calcium hardness precipitation rate and magnesium hardness precipitation rate as response values, at least 20 sets of experiments were designed based on a second-order universal rotational combination, of which 15 sets were factorial test points and 5 sets were repeating central test points, and the order of the test points in each set was randomly arranged. The above experimental results were subjected to regression analysis to obtain regression models of calcium hardness, magnesium hardness, and alkalinity with the proportion of calcium carbonate content during the electrolytic water precipitation process under non-aeration conditions. The significance of these models was verified and the regression model of P was determined. (3) Set the target value of calcium carbonate content to 95%, determine the ratio of aeration flow rate to influent flow rate, i.e., the air-to-water ratio, and under no aeration conditions, the difference between the calcium carbonate content and 95% is P. 差 (%) P 差 =95-P Regression analysis was performed on the experimental results to obtain the difference P between calcium hardness, magnesium hardness, alkalinity, and calcium carbonate content under aeration conditions. 差 The regression model of the air-water ratio GF is determined by the ratio of (%) to the aeration flow rate to the influent flow rate, and the regression model of GF is determined after verifying its significance. (4) Obtain the calcium hardness, magnesium hardness and alkalinity of the cooling water to be electrolyzed, and substitute them into the regression model of P to obtain the percentage of calcium carbonate in the precipitate of electrolyzed water under the condition of no aeration. (5) Calculate the difference between the percentage of calcium carbonate content P (%) and 95% as P. 差 (%), calcium hardness, magnesium hardness, alkalinity, P 差 Substituting the values ​​into the regression model of GF, we obtain the air-to-water ratio GF under the condition of enhanced aeration. (6) During the electrolytic water precipitation process, the ratio of gas flow rate to influent flow rate is increased to the GF value obtained in step (5), thereby increasing the calcium carbonate content to the target value and realizing the application of electrolytic water precipitate in limestone wet flue gas desulfurization.

2. A method for increasing the calcium carbonate content in precipitates generated by water electrolysis, characterized in that, Includes the following steps: (1) Obtain the cooling water quality, including calcium hardness (A), magnesium hardness (B), and alkalinity (C), and substitute them into the regression equation for P to calculate the P value: P=109.407+13.636A-17.095B-22.13C-20.582AB+2.729AC+16.459BC+6.316AB 2 -2.58B 2 C-1.062ABC-0.068A 3 -1.063B 3 -0.012C 3 Under conditions of no aeration enhancement, the percentage of calcium carbonate in the precipitate of electrolyzed water was obtained (P). (2) Calculate the difference between the percentage of calcium carbonate and 95% under the condition of no aeration enhancement, and the value of P. 差 : P 差 =95-P P 差 Substitute into the regression model of GF: GF=-12.295+4.263A+2.351C+0.264P 差 -0.21AC-0.026AP 差 +0.286BC-0.279A 2 -0.523B 2 -0.168C 2 -0.003P 差 2 Under conditions of enhanced aeration, the air-to-water ratio GF; (3) During the electrolysis of water precipitation process, the ratio of gas flow rate to influent flow rate is increased to the GF value, thereby increasing the proportion of calcium carbonate content to the target value, so as to realize the application of electrolysis water precipitate in limestone wet flue gas desulfurization.

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