Calculation method for scale inhibition rate of air micro-nano bubbles

Abstract

The invention belongs to the field of circulating water scale inhibition, and provides an air micro-nano bubble scale inhibition rate calculation method which comprises the following steps: preparing original solutions, grouping the original solutions, adding air micro-nano bubbles, heating in a water bath and filtering, measuring the concentration of calcium ions, calculating a correction coefficient and calculating the scale inhibition rate. By introducing the correction coefficient and the scale inhibition ratio formula, the defects of the method for measuring the scale inhibition ratio by using the chemical scale inhibitor are improved, and the accuracy of measuring the scale inhibition ratio of the air micro-nano bubbles is improved.

Description

Technical Field

[0001] The invention relates to the field of circulating water scale inhibition, and in particular to a method for calculating the scale inhibition rate of air micro-nano bubbles. Background Art

[0002] Conventional chemical scale inhibitors can inhibit the formation of scale by complexing calcium ions with functional groups such as carboxylic acid, phosphonic acid or sulfonic acid groups or attaching to the active sites of calcium carbonate crystals to hinder the normal growth of calcium carbonate crystals. The solution with a certain calcium ion concentration is divided into two groups, one with scale inhibitor added and the other without. After heating in a water bath at a certain temperature for a certain period of time, the residual calcium ion concentration of the two groups is measured, and then the formula can be used to calculate the residual calcium ion concentration of the two groups. The scale inhibition rate of the corresponding scale inhibitor can be obtained. In the formula, η is the scale inhibition rate, ρ0 is the calcium ion concentration of the original solution, ρ1 is the residual calcium ion concentration after water bath heating without adding scale inhibitor, and ρ2 is the residual calcium ion concentration after water bath heating with adding scale inhibitor. Since EDTA has a stronger complexing ability for calcium ions than conventional chemical scale inhibitors, the measurement results are accurate, so the EDTA titration method can be used to determine the true concentration of residual calcium ions in the solution.

[0003] The experiment found that after using air micro-nano bubbles for scale inhibition, the sum of the remaining calcium ion concentration of the solution measured by the EDTA titration method and the amount of calcium ion loss in the solution calculated by the amount of scaling is less than the calcium ion concentration in the raw water and is not within the error range. Since the use of air micro-nano bubbles as a scale inhibitor will significantly increase the particle size of the scale body, it is easy to separate the scale body, and most of the scale body can be separated from the solution. Therefore, it is judged that the binding energy of EDTA for calcium ions is much smaller than the adsorption capacity of air micro-nano bubbles for calcium ions, resulting in the remaining calcium ion concentration of the solution measured by the EDTA titration method being lower than the actual remaining calcium ion concentration of the solution, which in turn causes the calculated air micro-nano bubble scale inhibition rate to deviate from the actual value. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a method for calculating the scale inhibition rate of air micro-nano bubbles, so as to solve the problem that the calculated scale inhibition rate of air micro-nano bubbles deviates from the true value because the binding energy of EDTA for calcium ions is much smaller than the adsorption capacity of air micro-nano bubbles for calcium ions.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A method for calculating the scale inhibition rate of air micro-nano bubbles, comprising:

[0007] preparing a stock solution comprising a predetermined calcium ion concentration and a predetermined bicarbonate concentration;

[0008] The original solution was divided into two parts to obtain an experimental group solution and a blank group solution;

[0009] Filling the experimental group solution with air micro-nano bubbles to obtain a bubble-containing solution;

[0010] Respectively heating the bubble-containing solution and the blank group solution in a water bath at a preset temperature and filtering them to obtain a first filtrate and a second filtrate;

[0011] Using EDTA titration method to measure the ion concentration of the first filtrate and the second filtrate respectively, to obtain a first calcium ion concentration and a second calcium ion concentration;

[0012] Substituting the preset temperature into a preset correction coefficient calculation formula to obtain an auxiliary correction coefficient;

[0013] The auxiliary correction coefficient, the first calcium ion concentration, and the second calcium ion concentration are input into a preset scale inhibition rate calculation formula to obtain an air micro-nano bubble scale inhibition rate calculation result.

[0014] Preferably, the process of constructing the correction coefficient calculation formula includes:

[0015] preparing a test solution comprising a predetermined calcium ion concentration and a predetermined bicarbonate concentration;

[0016] Filling the test solution with air micro-nano bubbles;

[0017] Heating and filtering the test solution after the bubbles are injected in a water bath at the preset temperature to obtain a scale body and a third filtrate;

[0018] Drying and weighing the scale to obtain the mass of the scale;

[0019] Determine the calcium ion concentration of the third filtrate by using EDTA titration method to obtain a third calcium ion concentration;

[0020] Inputting the mass of the scale into a preset calcium ion concentration calculation formula for calculation to obtain a fourth calcium ion concentration;

[0021] calculating a ratio of the fourth calcium ion concentration to the third calcium ion concentration to obtain a set of correction data;

[0022] The correction data at several groups of temperatures are obtained, and function fitting is performed based on all the correction data to obtain the correction coefficient calculation formula.

[0023] Preferably, the preset temperature includes any temperature between 30°C and 70°C.

[0024] Preferably, the calculation formula of the correction coefficient is: ξ=α3T 3 -α2T 2+α1T-α0; wherein ξ is the correction coefficient; T is temperature; α0, α1, α2 and α3 correspond to the zeroth, first, second and third order coefficients of temperature respectively.

[0025] Preferably, the calculation formula of the real scale inhibition rate is: Among them, η is the actual scale inhibition rate; ρ1 is the second calcium ion concentration; ρ2 is the first calcium ion concentration; ρ0 is the calcium ion concentration of the original solution.

[0026] Preferably, the calcium ion concentration calculation formula is: Wherein, ρ is the fourth calcium ion concentration; ρ 01 is the calcium ion concentration of the test solution; m b is the mass of the scale; M Ca2+ is the relative atomic mass of calcium ion; M CaCo3 is the relative molecular mass of calcium carbonate.

[0027] The present invention discloses the following technical effects:

[0028] The present invention provides a method for calculating the scale inhibition rate of air micro-nano bubbles. By introducing a correction coefficient and a scale inhibition rate formula, the problem that the calculated scale inhibition rate of air micro-nano bubbles deviates from the true value due to the fact that the binding energy of EDTA for calcium ions is much smaller than the adsorption capacity of air micro-nano bubbles for calcium ions is solved, thereby achieving improvement on the defects of the scale inhibition rate determination method using chemical scale inhibitors. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0030] Figure 1 A schematic diagram of the calculation process of the air micro-nano bubble scale inhibition rate provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0032] The purpose of the present invention is to provide a method for calculating the scale inhibition rate of air micro-nano bubbles, so as to solve the problem that the calculated scale inhibition rate of air micro-nano bubbles deviates from the true value because the binding energy of EDTA for calcium ions is much smaller than the adsorption capacity of air micro-nano bubbles for calcium ions.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] Figure 1 The schematic diagram of the calculation process of the scale inhibition rate of air micro-nano bubbles provided in the embodiment of the present invention is as follows: Figure 1 As shown, the present invention provides a method for calculating the scale inhibition rate of air micro-nano bubbles, comprising:

[0035] Step 100: preparing a raw solution containing a preset calcium ion concentration and a preset bicarbonate concentration;

[0036] Step 200: Divide the original solution into two parts to obtain an experimental group solution and a blank group solution;

[0037] Step 300: Filling the experimental group solution with air micro-nano bubbles to obtain a bubble-containing solution;

[0038] Step 400: heating the bubble-containing solution and the blank group solution in a water bath at a preset temperature and filtering them to obtain a first filtrate and a second filtrate;

[0039] Step 500: using EDTA titration method to measure the ion concentration of the first filtrate and the second filtrate respectively, to obtain a first calcium ion concentration and a second calcium ion concentration;

[0040] Step 600: Substitute the preset temperature into the preset correction coefficient calculation formula to obtain the auxiliary correction coefficient;

[0041] Step 700: input the auxiliary correction coefficient, the first calcium ion concentration and the second calcium ion concentration into a preset scale inhibition rate calculation formula to obtain the air micro-nano bubble scale inhibition rate calculation result.

[0042] Furthermore, the process of constructing the correction coefficient calculation formula includes:

[0043] preparing a test solution comprising a predetermined calcium ion concentration and a predetermined bicarbonate concentration;

[0044] Fill the test solution with air micro-nano bubbles;

[0045] The test solution after the bubbles are flushed is heated in a water bath and filtered at a preset temperature to obtain a scale body and a third filtrate;

[0046] The scale body is dried and weighed to obtain the mass of the scale body;

[0047] Determine the calcium ion concentration of the third filtrate using an EDTA titration method to obtain a third calcium ion concentration;

[0048] Input the mass of the scale into a preset calcium ion concentration calculation formula to calculate and obtain the fourth calcium ion concentration;

[0049] calculating the ratio of the fourth calcium ion concentration to the third calcium ion concentration to obtain a set of correction data;

[0050] Correction data at several groups of temperatures are obtained, and function fitting is performed based on all the correction data to obtain a correction coefficient calculation formula.

[0051] Optionally, the preset temperature includes any temperature between 30°C and 70°C.

[0052] Specifically, the calculation formula of the correction coefficient is: ξ=α3T 3 -α2T 2 +α1T-α0; where ξ is the correction coefficient; T is the temperature; α0, α1, α2 and α3 correspond to the zeroth, first, second and third order coefficients of the temperature respectively.

[0053] Furthermore, the calculation formula of the actual scale inhibition rate is: Among them, η is the actual scale inhibition rate; ρ1 is the second calcium ion concentration; ρ2 is the first calcium ion concentration; ρ0 is the calcium ion concentration of the original solution.

[0054] Specifically, the calcium ion concentration calculation formula is: Where, ρ is the fourth calcium ion concentration; ρ 01 is the calcium ion concentration of the test solution; m b is the mass of scale; M Ca2+ is the relative atomic mass of calcium ion; M CaCo3 is the relative molecular mass of calcium carbonate.

[0055] Furthermore, in order to verify the feasibility of the solution of this embodiment, 5 embodiments are provided, as follows:

[0056] 1) Embodiment 1

[0057] Prepare a solution with a calcium ion concentration of 361 mg / L and a bicarbonate concentration of 549 mg / L, introduce sufficient micro-nano bubbles, take 1L of the solution and heat it in a water bath at 30°C, 40°C, 50°C, 60°C and 70°C for 1 hour, filter it, dry and weigh the scale obtained by filtration, and use EDTA to determine the third calcium ion concentration of the filtrate obtained by filtration. Substitute the average mass of the scale into the fourth calcium ion concentration calculation formula to calculate the fourth calcium ion concentration of the filtrate after heating in a water bath at each temperature. Calculate the ratio of the fourth calcium ion concentration to the third calcium ion concentration to obtain the correction coefficient. Establish a functional relationship between the correction coefficient and the corresponding temperature, and the correction coefficient calculation formula ξ=3.0246*10 -5 T 3 -0.00473T 2 +0.23596T-2.10118 (this formula is obtained by fitting according to the above method).

[0058] Take the above 2L prepared solution and divide the solution into two groups, one for the experimental group and the other for the control group. Sufficient micro-nano bubbles are introduced into the experimental group and heated in a water bath at 70°C. After the water bath heating, the scale bodies in the micro-nano bubble group are dried and weighed. The average weight of the scale bodies in the experimental group is 153mg. The average calcium ion concentration in the experimental group solution after filtration is measured by EDTA titration method to be 187.12mg / L, and the average calcium ion concentration in the blank group solution is 223.03mg / L.

[0059] Substituting the experimental temperature of 70℃ into the correction coefficient calculation formula, the coefficient is 1.6134, and substituting it into the real scale inhibition rate calculation formula together with the average calcium ion concentration in the experimental group solution after filtration and the average calcium ion concentration in the blank group solution measured by EDTA titration method, the real scale inhibition rate is 57.16%. Substituting the average mass of the scale body into the calcium ion concentration calculation formula, the fourth calcium ion concentration of the filtrate after water bath heating should be 305.76mg / L, and the scale inhibition rate can be calculated to be 59.96%. It can be seen that the error rate of this calculation method is 4.67%, which is less than 5%, and there is no significant difference.

[0060] 2) Embodiment 2

[0061] 2L of solution with a calcium ion concentration of 361mg / L and a bicarbonate concentration of 549mg / L was prepared, and the solution was divided into two groups, one for the experimental group and the other for the control group. Sufficient micro-nano bubbles were introduced into the experimental group and heated in a water bath at 50°C. After the water bath heating, the scale bodies in the micro-nano bubble group were dried and weighed. The average weight of the scale bodies in the experimental group was 68mg. The average calcium ion concentration in the experimental group solution after filtration was measured by EDTA titration method to be 200.95mg / L, and the average calcium ion concentration in the blank group solution was 243.21mg / L.

[0062] Substituting the experimental temperature of 50°C into the correction coefficient calculation formula in Example 1, the coefficient is 1.6526, and substituting it into the real scale inhibition rate calculation formula together with the average calcium ion concentration in the experimental group solution after filtration and the average calcium ion concentration in the blank group solution measured by EDTA titration method, the real scale inhibition rate is 75.45%, substituting the average mass of the scale body into the calcium ion concentration calculation formula to calculate that the fourth calcium ion concentration of the filtrate after water bath heating should be 336.45 mg / L, and the scale inhibition rate can be calculated to be 79.16%. It can be seen that the error rate of this calculation method is 4.68%, which is less than 5%, and there is no significant difference.

[0063] 3) Embodiment 3

[0064] 2L of solution with a calcium ion concentration of 451mg / L and a bicarbonate concentration of 687mg / L was prepared, and the solution was divided into two groups, one for the experimental group and the other for the control group. Sufficient micro-nano bubbles were introduced into the experimental group and heated in a water bath at 60°C. After the water bath heating, the scale bodies in the micro-nano bubble group were dried and weighed. The average weight of the scale bodies in the experimental group was 162mg. The average calcium ion concentration in the experimental group solution after filtration was measured by EDTA titration method to be 249.26mg / L, and the average calcium ion concentration in the blank group solution was 290.08mg / L.

[0065] Substituting the experimental temperature of 60°C into the correction coefficient calculation formula in Example 1, the coefficient is 1.5616, and substituting it into the real scale inhibition rate calculation formula together with the average calcium ion concentration in the experimental group solution after filtration and the average calcium ion concentration in the blank group solution measured by EDTA titration method, the real scale inhibition rate is 61.62%. Substituting the average mass of the scale body into the calcium ion concentration calculation formula, the fourth calcium ion concentration of the filtrate after water bath heating should be 392.51 mg / L, and the scale inhibition rate can be calculated to be 63.65%. It can be seen that the error rate of this calculation method is 3.20%, which is less than 5%, and there is no significant difference.

[0066] 4) Embodiment 4

[0067] 2L of solution with a calcium ion concentration of 541mg / L and a bicarbonate concentration of 824mg / L was prepared. The solution was divided into two groups, one for the experimental group and the other for the control group. Sufficient micro-nano bubbles were introduced into the experimental group and heated in a water bath at 40°C. After the water bath heating, the scale bodies in the micro-nano bubble group were dried and weighed. The average weight of the scale bodies in the experimental group was 133mg. The average calcium ion concentration in the experimental group solution after filtration was measured by EDTA titration method to be 291.37mg / L, and the average calcium ion concentration in the blank group solution was 390.00mg / L.

[0068] Substituting the experimental temperature of 40°C into the correction coefficient calculation formula in Example 1, the coefficient is 1.7050, and substituting it into the real scale inhibition rate calculation formula together with the average calcium ion concentration in the experimental group solution after filtration and the average calcium ion concentration in the blank group solution measured by EDTA titration method, the real scale inhibition rate is 70.71%. Substituting the average mass of the scale body into the calcium ion concentration calculation formula, the fourth calcium ion concentration of the filtrate after water bath heating should be 492.98 mg / L, and the scale inhibition rate can be calculated to be 68.20%. It can be seen that the error rate of this calculation method is 3.69%, which is less than 5%, and there is no significant difference.

[0069] 5) Embodiment 5

[0070] 2L of solution with a calcium ion concentration of 361mg / L and a bicarbonate concentration of 549mg / L was prepared, and the solution was divided into two groups, one for the experimental group and the other for the control group. Sufficient micro-nano bubbles were introduced into the experimental group and heated in a water bath at 30°C. After the water bath heating, the scale bodies introduced with micro-nano bubbles were dried and weighed. The average weight of the scale bodies in the experimental group was 72mg. The average calcium ion concentration in the experimental group solution after filtration was measured by EDTA titration method to be 215.85mg / L, and the average calcium ion concentration in the blank group solution was 267.94mg / L.

[0071] Substituting the experimental temperature of 30°C into the correction coefficient calculation formula in Example 1, the coefficient is 1.5373, and substituting it into the real scale inhibition rate calculation formula together with the average calcium ion concentration in the experimental group solution after filtration and the average calcium ion concentration in the blank group solution measured by EDTA titration method, the real scale inhibition rate is 68.64%, and substituting the average mass of the scale body into the calcium ion concentration calculation formula to calculate that the fourth calcium ion concentration of the filtrate after water bath heating should be 335.00 mg / L, and the scale inhibition rate can be calculated to be 72.07%. It can be seen that the error rate of this calculation method is 4.75%, which is less than 5%, and there is no significant difference.

[0072] The beneficial effects of the present invention are as follows:

[0073] The present invention introduces a correction coefficient and a scale inhibition rate formula to solve the problem that the binding energy of EDTA for calcium ions is much smaller than the adsorption capacity of air micro-nano bubbles for calcium ions, which causes the calculated air micro-nano bubble scale inhibition rate to deviate from the true value, thereby achieving accurate measurement of the micro-nano bubble scale inhibition rate.

[0074] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0075] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for calculating the scale inhibition rate of air micro-nano bubbles, characterized in that: include: preparing a stock solution comprising a predetermined calcium ion concentration and a predetermined bicarbonate concentration; The original solution was divided into two parts to obtain an experimental group solution and a blank group solution; Filling the experimental group solution with air micro-nano bubbles to obtain a bubble-containing solution; Respectively heating the bubble-containing solution and the blank group solution in a water bath at a preset temperature and filtering them to obtain a first filtrate and a second filtrate; Using EDTA titration method to measure the ion concentration of the first filtrate and the second filtrate respectively, to obtain a first calcium ion concentration and a second calcium ion concentration; Substituting the preset temperature into a preset correction coefficient calculation formula to obtain an auxiliary correction coefficient; The auxiliary correction coefficient, the first calcium ion concentration, and the second calcium ion concentration are input into a preset scale inhibition rate calculation formula to obtain an air micro-nano bubble scale inhibition rate calculation result.

2. The method for calculating the scale inhibition rate of air micro-nano bubbles according to claim 1 is characterized in that: The process of constructing the correction coefficient calculation formula includes: preparing a test solution comprising a predetermined calcium ion concentration and a predetermined bicarbonate concentration; Filling the test solution with air micro-nano bubbles; Heating and filtering the test solution after the bubbles are injected in a water bath at the preset temperature to obtain a scale body and a third filtrate; Drying and weighing the scale to obtain the mass of the scale; Determine the calcium ion concentration of the third filtrate by using EDTA titration method to obtain a third calcium ion concentration; Inputting the mass of the scale into a preset calcium ion concentration calculation formula for calculation to obtain a fourth calcium ion concentration; calculating a ratio of the fourth calcium ion concentration to the third calcium ion concentration to obtain a set of correction data; The correction data at several groups of temperatures are obtained, and function fitting is performed based on all the correction data to obtain the correction coefficient calculation formula.

3. The method for calculating the scale inhibition rate of air micro-nano bubbles according to claim 1 is characterized in that: The preset temperature includes any temperature between 30°C and 70°C.

4. The method for calculating the scale inhibition rate of air micro-nano bubbles according to claim 1 is characterized in that: The calculation formula of the correction coefficient is: ξ=α3T 3 -α2T 2 +α1T-α0; wherein ξ is the correction coefficient; T is temperature; α0, α1, α2 and α3 correspond to the zeroth, first, second and third order coefficients of temperature respectively.

5. The method for calculating the scale inhibition rate of air micro-nano bubbles according to claim 1 is characterized in that: The calculation formula of the actual scale inhibition rate is: Among them, η is the actual scale inhibition rate; ρ1 is the second calcium ion concentration; ρ2 is the first calcium ion concentration; ρ0 is the calcium ion concentration of the original solution.

6. The method for calculating the scale inhibition rate of air micro-nano bubbles according to claim 2 is characterized in that: The calcium ion concentration calculation formula is: Wherein, ρ is the fourth calcium ion concentration; ρ 01 is the calcium ion concentration of the test solution; m b is the mass of the scale; M Ca2+ is the relative atomic mass of calcium ion; M CaCo3 is the relative molecular mass of calcium carbonate.

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