A method and system for detecting the granularity of calcium carbonate

Abstract

The application relates to the technical field of calcium carbonate granularity detection, and particularly discloses a calcium carbonate granularity detection method and system, which relates to the technical field of calcium carbonate granularity detection, and realizes the precise cooperation of a dispersant and ultrasonic waves through four steps: step one, determining the static saturation concentration, adsorption relaxation time and re-agglomeration starting time of the dispersant; step two, establishing a correlation model of the dynamic saturation concentration under different ultrasonic energies and determining the critical value of the ultrasonic energy; step three, calculating an imbalance risk index to determine whether the dispersion system is imbalanced; and step four, optimizing the dispersion system according to the imbalance risk type, supplementing the dispersant when the concentration gap is dominant, and adopting pulse ultrasonic waves and determining the parameters of the pulse ultrasonic waves when the energy overrun is dominant, so that the core contradiction between the cooperation and confrontation of the dispersant and ultrasonic waves is solved, calcium carbonate particles are stably dispersed and precisely detected, and the detection precision and efficiency are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of calcium carbonate particle size detection, and particularly relates to a calcium carbonate particle size detection method and system. BACKGROUND

[0002] In the process of calcium carbonate particle size detection, the dispersion effect directly determines the accuracy and reliability of the detection result. The interaction between the dispersant and the ultrasound is an invisible variable of calcium carbonate particle dispersion. The core contradiction is that the dispersant needs sufficient concentration to form effective repulsion to assist dispersion, but too high concentration or dispersant not resistant to ultrasound will be destroyed by ultrasound energy, and thus lose the effect. This problem is particularly prominent in calcium carbonate detection, because the surface of calcium carbonate is highly polar, the agglomeration energy (van der Waals force + hydrogen bond) is high, and the dependence on the dispersant is stronger, while ultrasound is the main means to break the agglomeration, and the synergy and antagonism of the two directly determine the dispersion effect.

[0003] In the prior art, the regulation of dispersant concentration and ultrasound parameters depends on experience, and lacks quantitative correlation models and imbalance risk judgment standards. Either the agglomeration cannot be completely broken due to insufficient dispersant concentration, resulting in a large detection result, or the dispersant is degraded and the particles are broken due to excessive ultrasound energy, resulting in distorted detection results. At the same time, for the scenario where the ultrasound energy exceeds the tolerance threshold of the dispersant, there is a lack of effective alternative ultrasound mode and parameter design method, making it difficult to achieve stable dispersion and accurate detection of calcium carbonate particles.

[0004] Therefore, the present application provides a calcium carbonate particle size detection method and system. SUMMARY

[0005] The present application aims to provide a calcium carbonate particle size detection method and system to solve the above background problems.

[0006] The purpose of the present application can be achieved by the following technical solutions: a calcium carbonate particle size detection method, comprising:

[0007] The dispersant static saturation concentration is determined by performing a dispersant concentration gradient experiment on the calcium carbonate sample, and the dispersant adsorption equilibrium time parameter is recorded;

[0008] The dispersant dynamic saturation concentration under different ultrasound energy densities is obtained through an ultrasound energy density gradient pre-experiment based on the dispersant static saturation concentration as a reference, and the ultrasound energy density critical value is obtained through segmented fitting of the ultrasound energy density and the dynamic saturation concentration, so as to segment modeling based on the ultrasound energy density critical value to obtain the ultrasound energy density-dynamic saturation concentration correlation model;

[0009] The theoretical dispersant concentration is calculated according to the correlation model of ultrasonic energy density and dynamic saturation concentration, the concentration gap ratio is calculated by calculating the deviation of the current dispersant concentration and the theoretical dispersant concentration, the energy overrun ratio is calculated by calculating the ratio of the current ultrasonic energy density and the critical value of the ultrasonic energy density, and the imbalance risk index is calculated according to the concentration gap ratio and the energy overrun ratio. If the imbalance risk index meets the requirements, the current dispersion system has an ultrasonic imbalance risk.

[0010] The imbalance risk type is determined according to the ratio analysis of the current ultrasonic energy density and the critical value of the ultrasonic energy density, and the dispersion system is optimized in combination with the dispersant adsorption equilibrium time parameter.

[0011] Further, the determination method of the dispersant static saturation concentration and the dispersant adsorption equilibrium time parameter is:

[0012] In the fixed concentration of calcium carbonate suspension, different concentration gradient of dispersant is added, the corresponding Zeta potential and particle size of the dispersant under each concentration gradient are measured, and the Zeta potential sequence and particle size sequence are integrated respectively.

[0013] The first static saturation concentration is determined by the Zeta potential sequence, and the second static saturation concentration is determined by the particle size sequence.

[0014] The dispersant static saturation concentration is the maximum value of the first static saturation concentration and the second static saturation concentration.

[0015] The dispersant adsorption equilibrium time parameter includes the adsorption relaxation time and the dispersion system re-agglomeration starting time.

[0016] The adsorption relaxation time is the time required for the Zeta potential to be stable from the addition of the dispersant to the reading under the stirring of the dispersant at the static saturation concentration.

[0017] The agglomeration starting time is the time required for the particle size to meet the requirements for the first time under the static state of the dispersant at the static saturation concentration.

[0018] Further, the determination method of the first static saturation concentration and the second static saturation concentration is:

[0019] The Zeta potential change rate of adjacent Zeta potential in the Zeta potential sequence is calculated, and if two or more Zeta potential change rates meet the requirements, the dispersant concentration corresponding to the first Zeta potential meeting the requirements is the first static saturation concentration.

[0020] The particle size change rate of adjacent particle size in the particle size sequence is calculated, and the lowest dispersant concentration at which the particle size meets the requirements and reaches the stable minimum value is the second static saturation concentration.

[0021] Further, the determination method of the dynamic saturation concentration under different ultrasonic energy densities is:

[0022] Based on the static saturation concentration of the dispersant, a plurality of dispersant concentration gradients are set, and a plurality of ultrasonic energy density gradients are set according to the actual detection range of the energy coverage;

[0023] For any one group of ultrasonic energy density:

[0024] According to the dispersant concentration gradient, a corresponding volume of dispersant mother liquor is added to the centrifugal tube, and the samples are ultrasonically treated one by one according to the ultrasonic energy density gradient under the same amount of calcium carbonate sample. After the ultrasonic treatment is completed, the particle size of each sample is measured;

[0025] The lowest dispersant concentration at which the particle size reaches the minimum stable value is the dynamic saturation concentration under the ultrasonic energy density.

[0026] Further, the determination method of the ultrasonic energy density critical value is:

[0027] The ultrasonic energy density-dynamic saturation concentration data in the full energy range is divided into continuous energy sections at a fixed interval;

[0028] The local slope of each energy section is calculated, and the slope change rate of the adjacent two energy sections is calculated. The starting point of the energy section corresponding to the first time the slope change rate meets the requirement is the ultrasonic energy density critical point.

[0029] Further, the construction process of the ultrasonic energy density-dynamic saturation concentration correlation model is:

[0030] The ultrasonic energy density is divided into a linear section and a nonlinear section according to the ultrasonic energy density critical point;

[0031] The ultrasonic energy density is taken as the independent variable, and the dynamic saturation concentration is taken as the dependent variable;

[0032] The ultrasonic energy density-dynamic saturation concentration of the linear section is linearly fitted to obtain the ultrasonic energy density-dynamic saturation concentration correlation model;

[0033] The ultrasonic energy density-dynamic saturation concentration of the nonlinear section is fitted by a quadratic function to obtain the ultrasonic energy density-dynamic saturation concentration correlation model.

[0034] Further, the calculation method of the theoretical dispersant concentration is:

[0035] If the current ultrasonic energy density is less than or equal to the ultrasonic energy density critical point, the linear model is used, otherwise the nonlinear model is used. The current ultrasonic energy density is substituted into the ultrasonic energy density-dynamic saturation concentration to obtain the theoretical dispersant concentration.

[0036] Further, the imbalance risk type judgment mode is:

[0037] If the current ultrasonic energy density is less than the ultrasonic energy density threshold value, the imbalance risk type is concentration gap dominant, otherwise it is energy overrun dominant.

[0038] Further, the process of optimizing the dispersion system is:

[0039] If the imbalance risk type is concentration gap dominant, the dispersant concentration is supplemented to the theoretical dispersant concentration, and the theoretical dispersant concentration is substituted into the ultrasonic energy density-dynamic saturation concentration correlation model to calculate the corresponding ultrasonic energy density as the optimal parameter combination;

[0040] If the imbalance risk type is energy overrun dominant, pulse ultrasonic is performed:

[0041] The current dispersant concentration is substituted into the ultrasonic energy density-dynamic saturation concentration correlation model to calculate the theoretical ultrasonic energy density, and the total ultrasonic energy is calculated according to the formula total ultrasonic energy = theoretical ultrasonic energy density × sample volume;

[0042] The off time of pulse ultrasonic is [adsorption relaxation time, re-aggregation initiation time], the on time is half to one time of the off time, and the cycle number is total ultrasonic energy / ultrasonic power × single on time.

[0043] A calcium carbonate particle size detection system, comprising the following modules:

[0044] Static parameter calibration module: determine the dispersant static saturation concentration by dispersant concentration gradient experiment on calcium carbonate sample, and record the dispersant adsorption equilibrium time parameter;

[0045] Dynamic correlation modeling module: take the dispersant static saturation concentration as the benchmark, obtain the dispersant dynamic saturation concentration under different ultrasonic energy densities through ultrasonic energy density gradient pre-experiment, and obtain the ultrasonic energy density threshold value through piecewise fitting of ultrasonic energy density and dynamic saturation concentration. Segment modeling is performed with the ultrasonic energy density threshold value as the boundary to obtain the ultrasonic energy density-dynamic saturation concentration correlation model;

[0046] Imbalance risk determination module: calculate the theoretical dispersant concentration according to the correlation model of ultrasonic energy density and dynamic saturation concentration, and perform deviation analysis with the current dispersant concentration, combine the comparison analysis of current ultrasonic energy density and ultrasonic energy density threshold value, and judge whether the current dispersion system has ultrasonic imbalance risk;

[0047] Dispersion system optimization module: determine the imbalance risk type according to the comparison analysis of current ultrasonic energy density and ultrasonic energy density threshold value, and optimize the dispersion system combined with the dispersant adsorption equilibrium time parameter.

[0048] The beneficial effects of the present application are as follows:

[0049] 1. By establishing a correlation model between ultrasonic energy and dynamic saturation concentration, the dispersion agent concentration and ultrasonic parameters are quantitatively matched, the blindness of traditional empirical control is solved, and the accuracy of detection is improved.

[0050] 2. The imbalance risk index is introduced, the imbalance degree of the dispersion system is quantified by the concentration gap ratio and the energy overrun ratio, the dispersion risk can be predicted in advance, and the detection error caused by improper parameters can be avoided.

[0051] 3. Different optimization strategies are adopted for different imbalance risk types, the dispersion agent is accurately supplemented when the concentration gap dominates, and the pulse ultrasonic is innovatively used when the energy overrun dominates, and the parameters are designed based on the adsorption relaxation time and the re-agglomeration starting time, which realizes the dynamic balance between the dispersion agent protection and the ultrasonic destruction, and ensures the stability of the dispersion effect.

[0052] 4. The whole method flow is logical and operable, the corresponding detection system is modularly designed, which is convenient for industrial application, and can significantly improve the efficiency and reliability of the calcium carbonate particle size detection. BRIEF DESCRIPTION OF DRAWINGS

[0053] The present application will be further described below with reference to the accompanying drawings.

[0054] Figure 1 is a flowchart of a calcium carbonate particle size detection method in embodiment 1 of the present application;

[0055] Figure 2 is a flowchart for determining whether the current dispersion system has ultrasonic imbalance risk in embodiment 1 of the present application;

[0056] Figure 3 is a functional module diagram of a calcium carbonate particle size detection method system in embodiment 2 of the present application. DETAILED DESCRIPTION

[0057] In order to make the technical means, creative features, purposes and effects achieved by the present application easy to understand, the present application will be further described below with reference to the specific embodiments.

[0058] Embodiment 1: Please refer to Figure 1 The calcium carbonate particle size detection method described in the embodiment of the present application comprises the following steps:

[0059] Step 1: Determine the dispersion agent static saturation concentration by performing a dispersion agent concentration gradient experiment on the calcium carbonate sample, and record the dispersion agent adsorption equilibrium time parameter;

[0060] In step one, the static saturation concentration is the minimum concentration of the dispersant under the condition of no ultrasonic adsorption-desorption equilibrium, reflecting the theoretical demand of the dispersant;

[0061] The determination process of the static saturation concentration of the dispersant includes:

[0062] The static saturation concentration is determined by Zeta potential and particle size, specifically:

[0063] Prepare a series of calcium carbonate suspensions with fixed concentrations, set a concentration gradient of the dispersant, for example: sodium hexametaphosphate, concentration gradient is 0.1%, 0.2%, 0.5%, 1.0%, 1.5%, 2.0%, etc.

[0064] Gently stir for thirty minutes using a magnetic stirrer to ensure that the dispersant is adsorbed and balanced;

[0065] Measure the corresponding Zeta potential and particle size (D50) of the dispersant under each concentration gradient, and integrate them into Zeta potential sequence and particle size sequence respectively;

[0066] First, the first static saturation concentration is determined by the Zeta potential sequence, specifically:

[0067] Calculate the Zeta potential change rate of adjacent Zeta potentials in the Zeta potential sequence, and compare it with the preset change rate. If there are two or more Zeta potential change rates less than the preset change rate, the dispersant concentration corresponding to the first Zeta potential less than the preset change rate is the first static saturation concentration;

[0068] Second, the second static saturation concentration is determined by the particle size sequence, specifically:

[0069] Calculate the particle size change rate of adjacent particle sizes in the particle size sequence. The lowest dispersant concentration at which the particle size change rate is less than the preset particle size change rate and the particle size reaches a stable minimum value is the second static saturation concentration;

[0070] The static saturation concentration of the dispersant is the maximum value of the first static saturation concentration and the second static saturation concentration;

[0071] It can be understood that the logic of determining the static saturation concentration is: the first static saturation concentration determined by Zeta potential mainly reflects the saturation point of electrostatic stabilization mechanism, and the second static saturation concentration determined by the minimum particle size reflects the best point of overall dispersion effect, including electrostatic stabilization and spatial stabilization mechanism. Selecting a higher concentration can ensure stable dispersion under various conditions and meet the needs of electrostatic stabilization and spatial stabilization at the same time;

[0072] The dispersant adsorption equilibrium time parameter includes adsorption relaxation time and dispersion system re-aggregation initiation time;

[0073] wherein the adsorption relaxation time is the time required for the dispersant molecules to be firmly adsorbed on the surface of the particles, and the determination process comprises:

[0074] Prepare a calcium carbonate suspension, add the static saturated concentration of dispersant, and start vigorous stirring at the same time;

[0075] Use a Zeta potential instrument to measure the Zeta potential every few seconds until the reading is stable;

[0076] The time required from the addition of the dispersant to the stable reading is the adsorption relaxation time;

[0077] The re-agglomeration initiation time is the time at which the particles begin to agglomerate obviously in the presence of the dispersant but without mechanical stirring, and the determination process comprises:

[0078] Place a well-dispersed calcium carbonate suspension under the static saturated concentration of dispersant without stirring;

[0079] Measure the particle size (D50) at fixed time intervals (such as 30 seconds, 1 minute, 2 minutes, etc.);

[0080] Draw a particle size-static time curve, and the time point at which the particle size increases by more than 5% is the re-agglomeration initiation time;

[0081] It should be noted that the determination of the static saturated concentration of the dispersant and the recording of the dispersant adsorption equilibrium time parameter serve to:

[0082] Provide a basic reference system for subsequent dynamic control and optimization, and solve the basic adaptation problem of the dispersant and the particles under the condition of no ultrasonic;

[0083] Step two: based on the static saturated concentration of the dispersant, obtain the dynamic saturated concentration of the dispersant under different ultrasonic energy densities through ultrasonic energy density gradient pre-experiment, and obtain the ultrasonic energy density critical value through segmented fitting of the ultrasonic energy density and the dynamic saturated concentration. The ultrasonic energy density critical value is used as a boundary to segment the modeling to obtain the ultrasonic energy density-dynamic saturated concentration correlation model;

[0084] In step two, the determination process of the dynamic saturated concentration under different ultrasonic energy densities comprises:

[0085] Based on the static saturated concentration of the dispersant, set multiple groups of dispersant concentration gradients;

[0086] Set multiple groups of ultrasonic energy density gradients according to the energy coverage of the actual detection range, wherein the ultrasonic energy density is quantified by ultrasonic power+time, and the formula is: ultrasonic energy density = total ultrasonic input energy / sample volume;

[0087] For each group of ultrasonic energy density, the dynamic saturation concentration under the ultrasonic energy density is found by the concentration-particle size relationship, specifically:

[0088] For any group of ultrasonic energy density:

[0089] According to the dispersant concentration gradient, corresponding volumes of dispersant mother liquor are added to centrifuge tubes, which are stirred uniformly, and an equal amount of calcium carbonate sample is added to each centrifuge tube;

[0090] According to the ultrasonic energy density gradient, the samples are ultrasonically processed one by one, and after the ultrasonic processing is completed, the particle size of each sample is measured by a laser particle size analyzer;

[0091] A dispersant concentration-ultrasonic energy curve is drawn, and the dynamic saturation concentration standard is determined as:

[0092] The particle size reaches a minimum stable value: D50 no longer decreases significantly with increasing dispersant concentration;

[0093] The lowest dispersant concentration that reaches the minimum stable value is taken as the dynamic saturation concentration under the ultrasonic energy density;

[0094] In step two, the construction process of the correlation model between the ultrasonic energy density and the dynamic saturation concentration includes:

[0095] It should be noted that in the dispersion of calcium carbonate, the relationship between ultrasonic energy and dynamic saturation concentration should comply with the destruction mechanism of ultrasonic on dispersant: when the ultrasonic energy is low, the dispersant mainly undergoes physical absorption (the destruction rate is proportional to the energy), and there is no obvious chemical degradation (such as chain scission), so the dynamic saturation concentration increases linearly with the ultrasonic energy;

[0096] When the ultrasonic energy is high, in addition to physical absorption, the dispersant also undergoes chemical degradation (high temperature / free radicals generated by ultrasonic cavitation cause molecular chain scission), and the degradation rate accelerates with increasing energy (the higher the energy, the more free radicals, the faster the degradation), so the growth rate of the dynamic saturation concentration with the ultrasonic energy increases;

[0097] The critical point of the linear and nonlinear models (ultrasonic energy critical) is the energy threshold at which ultrasonic energy changes from only causing physical absorption of dispersant to causing chemical degradation as well, and the determination process of the ultrasonic energy density critical value includes:

[0098] The ultrasonic energy density-dynamic saturation concentration data in the full energy range are divided into consecutive energy segments according to intervals;

[0099] The local slope of each energy segment is calculated, and the slope change rate of adjacent two segments is calculated;

[0100] When the slope change rate first exceeds the empirical threshold, the starting point of the corresponding energy segment is the ultrasonic energy density critical point;

[0101] The ultrasonic energy density is divided into a linear segment and a nonlinear segment by a critical point of ultrasonic energy density;

[0102] The ultrasonic energy density is divided into a linear segment and a nonlinear segment by a critical point of ultrasonic energy density;

[0103] The ultrasonic energy density is divided into a linear segment and a nonlinear segment by a critical point of ultrasonic energy density;

[0104] The ultrasonic energy density is divided into a linear segment and a nonlinear segment by a critical point of ultrasonic energy density;

[0105] It should be noted that the role of constructing the correlation model and determining the critical value of ultrasonic energy density is to establish the quantitative relationship between ultrasonic energy and dispersant demand, divide the safety / risk interval of ultrasonic action, and solve the problem of parameter adaptation without basis in a dynamic environment;

[0106] Step three: calculate the theoretical dispersant concentration according to the correlation model of ultrasonic energy density and dynamic saturation concentration, calculate the concentration gap ratio of the current dispersant concentration and the theoretical dispersant concentration, calculate the energy overrun ratio of the current ultrasonic energy density and the critical value of ultrasonic energy density, and calculate the imbalance risk index according to the concentration gap ratio and the energy overrun ratio. If the imbalance risk index meets the requirements, the current dispersing system has an ultrasonic imbalance risk;

[0107] Please refer to Figure 2 In step three, the calculation process of the theoretical dispersant concentration includes:

[0108] According to the current ultrasonic power, ultrasonic time and sample volume, the ultrasonic energy density of the current ultrasonic parameters is calculated, and the formula is: ultrasonic energy density=ultrasonic power×ultrasonic time / sample volume;

[0109] Based on the ultrasonic energy density-dynamic saturation density correlation model, the theoretical dispersant concentration required under the current ultrasonic condition is predicted;

[0110] If the current ultrasonic energy density is less than or equal to the critical point of ultrasonic energy density, use the linear model, and substitute the current ultrasonic energy density into the linear model to obtain the theoretical dispersant concentration;

[0111] If the current ultrasonic energy density is greater than the critical point of ultrasonic energy density, use the nonlinear model, and substitute the current ultrasonic energy density into the nonlinear model to obtain the theoretical dispersant concentration;

[0112] In step three, the judgment process of whether the current dispersing system has an ultrasonic imbalance risk includes:

[0113] a concentration gap ratio is calculated by calculating the deviation of the current dispersant concentration from the theoretical dispersant concentration;

[0114] an energy over-limit ratio is calculated by comparing the current ultrasonic energy density with the ultrasonic energy density threshold value;

[0115] an imbalance risk index is obtained by adding the concentration gap ratio and the energy over-limit ratio;

[0116] It can be understood that the physical meaning of the imbalance risk index is a comprehensive index of the deviation of the system from the ideal dispersion state, representing the overall imbalance degree of the protection- destruction pair of contradictions, and the larger the value, the more the system deviates from the ideal point of stable dispersion;

[0117] The concentration gap ratio represents the relative degree of insufficient dispersant supply, reflecting the gap ratio of the current dispersant concentration relative to the theoretical demand under the dynamic ultrasonic environment, and essentially quantifying the lack of protection at the molecular level;

[0118] The energy over-limit ratio represents the relative degree of excessive energy input, reflecting the over-limit multiple of the current ultrasonic energy relative to the safety threshold, and essentially quantifying the mechanical damage force;

[0119] The imbalance risk index is compared with the preset risk index, and if the imbalance risk index is greater than the preset risk index, the current dispersion system has an ultrasonic imbalance risk;

[0120] It should be noted that the preset risk index is the maximum deviation degree of an acceptable dispersion system, defining the boundary between acceptable and unacceptable dispersion effects, and is set based on the detection accuracy requirement;

[0121] It should be noted that the role of determining whether the current dispersion system has an ultrasonic imbalance risk is to predict the stability of the dispersion system through the deviation analysis of the theoretical parameters and the current parameters, and to solve the problem of blindness in judging the dispersion effect based on experience;

[0122] Step four: determining the imbalance risk type according to the comparison analysis of the current ultrasonic energy density and the ultrasonic energy density threshold value, and optimizing the dispersion system in combination with the dispersant adsorption equilibrium time parameter;

[0123] In step four, the determination process of the imbalance risk type includes:

[0124] If the current ultrasonic energy density is less than the ultrasonic energy density threshold value, the imbalance risk type is dominated by the concentration gap;

[0125] If the current ultrasonic energy density is greater than or equal to the ultrasonic energy density threshold value, the imbalance risk type is dominated by the energy over-limit;

[0126] In step four, the process of optimizing the dispersion system by the adsorption equilibrium time parameter of the combined dispersant includes:

[0127] If the imbalance risk type is dominated by concentration gap;

[0128] The dispersant concentration is supplemented to the theoretical dispersant concentration, and the corresponding ultrasonic energy is calculated by combining the correlation model of ultrasonic energy and dynamic saturation concentration as the optimal parameter combination;

[0129] If the imbalance risk type is dominated by energy overrun;

[0130] Pulse ultrasonic is selected, and the on-off cycle, cycle number and ultrasonic power of pulse ultrasonic are determined, specifically:

[0131] The current dispersant concentration is substituted into the ultrasonic energy density-dynamic saturation concentration correlation model to calculate the theoretical ultrasonic energy density;

[0132] The total ultrasonic energy is calculated according to the theoretical ultrasonic energy density, and the formula is: total ultrasonic energy = ultrasonic energy density × sample volume;

[0133] It should be noted that the on period is a destroyer that provides mechanical energy to break up agglomerates and expose fresh surfaces, and the off period is a builder that provides a quiet window for dispersant molecules to diffuse, adsorb, anchor and establish a stable protective layer. The best pulse condition is to make the speed and quality of construction keep up with or even exceed the pace of destruction, so as to achieve net dispersion effect in the dynamic;

[0134] First, it should be noted that the off time is set, specifically:

[0135] The off time must be greater than the adsorption relaxation time of the dispersant to ensure that the dispersant has enough time to complete adsorption;

[0136] The off time must be less than the re-agglomeration initiation time of the system to ensure that the next ultrasonic pulse is turned on before re-agglomeration occurs;

[0137] Therefore, the off time interval is [adsorption relaxation time, re-agglomeration initiation time];

[0138] Second, it should be noted that the on time is set, specifically:

[0139] It should be noted that the on time should be long enough to effectively break up the soft agglomerates that may form in this off period and the hard agglomerates that have not been resolved by the previous dispersion, but not too long to avoid local overheating and desorption of the dispersant;

[0140] The on time is set to 1 / 2 to 1 times the off time, for example, if the off time is 6 seconds, the on time can be tested for 3 seconds, 5 seconds, 6 seconds;

[0141] Thirdly, the number of cycles is calculated, specifically:

[0142] The total ultrasonic energy of the pulsed ultrasound is provided only by the on-time (the off-time is used for adsorption and does not generate ultrasonic energy), so: total ultrasonic energy = ultrasonic power x total on-time, and total on-time = number of cycles x single on-time;

[0143] Therefore, the number of cycles is total ultrasonic energy / ultrasonic power x single on-time;

[0144] It should be noted that the role of targeted optimization according to the imbalance risk type is: accurate measures according to the risk type, reconstruction of the protection- destruction balance through parameter adjustment, and finally obtain the optimal parameter combination of stable dispersion, to ensure the detection accuracy.

[0145] The technical scheme and advantages of the embodiment of the application are: the static saturation concentration of the dispersant is determined by performing a dispersant concentration gradient experiment on the calcium carbonate sample, and the dispersant adsorption equilibrium time parameter is recorded, the dynamic saturation concentration of the dispersant under different ultrasonic energy densities is obtained by ultrasonic energy density gradient pre-experiment based on the static saturation concentration of the dispersant, the ultrasonic energy density critical value is obtained by piecewise fitting of the ultrasonic energy density and the dynamic saturation concentration, the ultrasonic energy density-dynamic saturation concentration correlation model is obtained by piecewise modeling based on the ultrasonic energy density critical value, the theoretical dispersant concentration is calculated according to the correlation model of the ultrasonic energy density and the dynamic saturation concentration, and the deviation analysis is performed on the current dispersant concentration, the current ultrasonic energy density is compared with the ultrasonic energy density critical value, and it is judged whether the current dispersion system has an ultrasonic imbalance risk, if there is, the imbalance risk type is determined according to the comparison of the current ultrasonic energy density and the ultrasonic energy density critical value, and the dispersion system is optimized in combination with the dispersant adsorption equilibrium time parameter. The application realizes the quantitative matching of the dispersant concentration and the ultrasonic parameters by establishing the correlation model of the ultrasonic energy and the dynamic saturation concentration, solves the blindness of traditional empirical control, improves the accuracy of detection, introduces the imbalance risk index, quantifies the imbalance degree of the dispersion system through the concentration gap ratio and the energy overrun ratio, can predict the dispersion risk in advance, avoids the detection error caused by improper parameters, adopts differentiated optimization strategies for different imbalance risk types, accurately supplements the dispersant when the concentration gap dominates, innovatively uses pulsed ultrasound when the energy overrun dominates, and designs parameters based on adsorption relaxation time and re-agglomeration starting time, realizes the dynamic balance of the protective effect of the dispersant and the destructive effect of the ultrasound, ensures the stability of the dispersion effect, the whole method process is logical and operable, the corresponding detection system is modularly designed, and industrial application is facilitated, which can significantly improve the efficiency and reliability of the calcium carbonate particle size detection.

[0146] Embodiment 2: Please refer to Figure 3 As shown in the figure, the calcium carbonate particle size detection system according to the embodiment of the application comprises the following modules:

[0147] Static parameter calibration module: the static saturation concentration of the dispersant is determined by performing a dispersant concentration gradient experiment on the calcium carbonate sample, and the dispersant adsorption equilibrium time parameter is recorded;

[0148] Dynamic correlation modeling module: taking the static saturation concentration of the dispersant as a benchmark, the dynamic saturation concentration of the dispersant under different ultrasonic energy densities is obtained through a pre-experiment of ultrasonic energy density gradient, and the ultrasonic energy density critical value is obtained through segmented fitting of the ultrasonic energy density and the dynamic saturation concentration, so as to obtain the ultrasonic energy density-dynamic saturation concentration correlation model by segmented modeling according to the ultrasonic energy density critical value;

[0149] Unbalance risk judgment module: the theoretical dispersant concentration is calculated according to the correlation model of the ultrasonic energy density and the dynamic saturation concentration, the concentration gap ratio is obtained by calculating the deviation between the current dispersant concentration and the theoretical dispersant concentration, the energy overrun ratio is obtained by calculating the ratio of the current ultrasonic energy density to the ultrasonic energy density critical value, and the unbalance risk index is calculated according to the concentration gap ratio and the energy overrun ratio, so that the current dispersion system has an ultrasonic unbalance risk if the unbalance risk index meets the requirements;

[0150] Dispersion system optimization module: the unbalance risk type is determined according to the comparison analysis of the current ultrasonic energy density and the ultrasonic energy density critical value, and the dispersion system is optimized in combination with the dispersant adsorption equilibrium time parameter;

[0151] The above has described one embodiment of the present application in detail, but the content described is only the preferred embodiment of the present application, and cannot be considered as limiting the scope of the implementation of the present application. Any equivalent changes and improvements made within the scope of the present application should still belong to the scope of the present application.

Claims

1. A method for detecting the particle size of calcium carbonate, characterized in that: Includes the following steps: The static saturation concentration of the dispersant was determined by conducting a dispersant concentration gradient experiment on the calcium carbonate sample, and the dispersant adsorption equilibrium time parameter was recorded. Using the static saturation concentration of the dispersant as a benchmark, the dynamic saturation concentration of the dispersant under different ultrasonic energy densities was obtained through preliminary experiments on ultrasonic energy density gradient. The critical value of ultrasonic energy density was obtained by piecewise fitting of ultrasonic energy density and dynamic saturation concentration. The ultrasonic energy density-dynamic saturation concentration correlation model was obtained by piecewise modeling with the critical value of ultrasonic energy density as the boundary. The theoretical dispersant concentration is calculated based on the correlation model between ultrasonic energy density and dynamic saturation concentration. The concentration gap ratio is obtained by calculating the deviation between the current dispersant concentration and the theoretical dispersant concentration. The energy over-limit ratio is obtained by calculating the ratio between the current ultrasonic energy density and the ultrasonic energy density critical value. The imbalance risk index is calculated based on the concentration gap ratio and the energy over-limit ratio. If the imbalance risk index meets the requirements, then the current dispersion system has an ultrasonic imbalance risk. The type of imbalance risk is determined by comparing the current ultrasonic energy density with the critical value of ultrasonic energy density, and the dispersion system is optimized by combining the dispersant adsorption equilibrium time parameter. The process of optimizing the dispersed system is as follows: If the imbalance risk type is dominated by concentration gap, the dispersant concentration is supplemented to the theoretical dispersant concentration, and the theoretical dispersant concentration is substituted into the ultrasonic energy density-dynamic saturation concentration correlation model to calculate the corresponding ultrasonic energy density, which is used as the optimal parameter combination; If the imbalance risk type is dominated by energy excess, pulsed ultrasound should be performed: Substitute the current dispersant concentration into the ultrasonic energy density-dynamic saturation concentration correlation model to calculate the theoretical ultrasonic energy density. The total ultrasonic energy is then calculated according to the formula: Total ultrasonic energy = Theoretical ultrasonic energy density × Sample volume. The off time of pulsed ultrasound is [adsorption relaxation time + reaggregation initiation time], and the on time is half to twice the off time. The number of cycles is the total ultrasound energy / ultrasound power × single on time.

2. The method for detecting calcium carbonate particle size according to claim 1, characterized in that: The static saturation concentration of the dispersant and the dispersant adsorption equilibrium time parameters are determined as follows: Dispersants with different concentration gradients were added to a calcium carbonate suspension of fixed concentration. The zeta potential and particle size of the dispersants at each concentration gradient were measured and integrated into zeta potential sequences and particle size sequences, respectively. The first static saturation concentration was determined by the zeta potential sequence, and the second static saturation concentration was determined by the particle size sequence. The static saturation concentration of the dispersant is the maximum value between the first static saturation concentration and the second static saturation concentration; The dispersant adsorption equilibrium time parameters include adsorption relaxation time and the reagglomeration initiation time of the dispersion system; The adsorption relaxation time is the time required for the Zeta potential of the dispersion system to stabilize from the addition of the dispersant under static stirring with a saturated concentration of dispersant. Agglomeration initiation time is the time required for the particle size change of the dispersion system to first meet the requirements under static saturated concentration dispersant conditions.

3. The method for detecting calcium carbonate particle size according to claim 2, characterized in that: The first static saturation concentration and the second static saturation concentration are determined as follows: Calculate the rate of change of Zeta potential between adjacent Zeta potentials in the Zeta potential sequence. If two or more Zeta potential rates of change meet the requirements, the dispersant concentration corresponding to the first Zeta potential that meets the requirements is the first static saturation concentration. Calculate the particle size change rate of adjacent particle sizes in the particle size sequence. The lowest dispersant concentration where the particle size change rate meets the requirements and the particle size reaches a stable minimum value is the second static saturation concentration.

4. The method for detecting calcium carbonate particle size according to claim 1, characterized in that: The method for determining the dynamic saturation concentration under different ultrasonic energy densities is as follows: Based on the static saturation concentration of the dispersant, multiple sets of dispersant concentration gradients were set, and multiple sets of ultrasonic energy density gradients were set according to the energy coverage of the actual detection range. For any set of ultrasonic energy densities: Add the corresponding volume of dispersant stock solution to centrifuge tubes according to the dispersant concentration gradient. Under the same amount of calcium carbonate sample, sonicate the samples one by one according to the ultrasonic energy density gradient. After sonication, measure the particle size of each sample. The minimum dispersant concentration at which the particle size reaches its minimum stable value is the dynamic saturation concentration under ultrasonic energy density.

5. The method for detecting calcium carbonate particle size according to claim 4, characterized in that: The method for determining the critical value of ultrasonic energy density is as follows: The ultrasonic energy density-dynamic saturation concentration data across the entire energy range are divided into continuous energy segments at fixed intervals; Calculate the local slope of each energy segment and the rate of change of slope between two adjacent energy segments. The starting point of the energy segment that first meets the requirement for the rate of change of slope is the critical point of ultrasonic energy density.

6. The method for detecting calcium carbonate particle size according to claim 5, characterized in that: The process of constructing the ultrasonic energy density-dynamic saturation concentration correlation model is as follows: The ultrasonic energy density is divided into linear and nonlinear segments, with the critical point of ultrasonic energy density as the boundary. Ultrasonic energy density was used as the independent variable and dynamic saturation concentration as the dependent variable; A linear fitting was performed on the ultrasonic energy density-dynamic saturation concentration of the linear segment to obtain the ultrasonic energy density-dynamic saturation concentration correlation model. A quadratic function was fitted to the ultrasonic energy density-dynamic saturation concentration in the nonlinear segment to obtain the ultrasonic energy density-dynamic saturation concentration correlation model.

7. The method for detecting calcium carbonate particle size according to claim 6, characterized in that: The theoretical dispersant concentration is calculated as follows: If the current ultrasonic energy density is less than or equal to the ultrasonic energy density critical point, a linear model is used; otherwise, a nonlinear model is used. The current ultrasonic energy density is substituted into the ultrasonic energy density minus the dynamic saturation concentration to obtain the theoretical dispersant concentration.

8. The method for detecting calcium carbonate particle size according to claim 1, characterized in that: The method for determining the type of imbalance risk is as follows: If the current ultrasound energy density is less than the critical value of ultrasound energy density, the imbalance risk type is dominated by concentration gap; otherwise, it is dominated by energy over-limit.

9. A calcium carbonate particle size detection system, characterized in that, The system is used to perform the method according to any one of claims 1-8, the system comprising: Static parameter calibration module: The static saturation concentration of the dispersant is determined by conducting a dispersant concentration gradient experiment on the calcium carbonate sample, and the dispersant adsorption equilibrium time parameter is recorded; Dynamic correlation modeling module: Based on the static saturation concentration of the dispersant, the dynamic saturation concentration of the dispersant under different ultrasonic energy densities is obtained through preliminary experiments on ultrasonic energy density gradient. The critical value of ultrasonic energy density is obtained by piecewise fitting of ultrasonic energy density and dynamic saturation concentration. The ultrasonic energy density-dynamic saturation concentration correlation model is obtained by piecewise modeling with the critical value of ultrasonic energy density as the boundary. Imbalance Risk Assessment Module: The theoretical dispersant concentration is calculated based on the correlation model between ultrasonic energy density and dynamic saturation concentration. The deviation between the current dispersant concentration and the theoretical dispersant concentration is calculated to obtain the concentration gap ratio. The ratio between the current ultrasonic energy density and the ultrasonic energy density critical value is calculated to obtain the energy over-limit ratio. The imbalance risk index is calculated based on the concentration gap ratio and the energy over-limit ratio. If the imbalance risk index meets the requirements, the current dispersion system has an ultrasonic imbalance risk. Dispersion system optimization module: Based on the comparison analysis between the current ultrasonic energy density and the ultrasonic energy density critical value, the imbalance risk type is determined, and the dispersion system is optimized in combination with the dispersant adsorption equilibrium time parameter.

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