Preparation system of high-dispersion silicon dioxide

Abstract

The invention provides a preparation system of high-dispersion silicon dioxide, compared with the prior art, the preparation system comprises a preliminary mixing module, a cleaning module and a drying module, the preliminary mixing module is used for mixing a sodium silicate solution with the concentration of 15-35% and mixed acid until the pH value is 4-5.5, and the mixed solution is mixed at 60-65 DEG C; the cleaning module is used for repeatedly washing precipitates in the mixed liquid and filtering the precipitates to obtain a filter cake, and the drying module is used for dehydrating the filter cake in an environment of 25-60 DEG C until the filter cake is dried to obtain silicon dioxide powder. According to the method, key parameters such as the pH value, the viscosity and the liquid level height are monitored in real time, the stirring speed and the acid liquid titration amount which are dynamically adjusted are combined, it is ensured that the mixed liquid can rapidly and accurately reach the target pH range, and the preparation efficiency is remarkably improved.

Description

Technical Field

[0001] The invention relates to the field of chemical production, and in particular to a preparation system of highly dispersed silicon dioxide. Background Art

[0002] In the modern rubber industry, silica is a key reinforcing material and is widely used in tires, seals and other high-performance rubber products. By optimizing the specific surface area and dispersion properties of silica, the mechanical strength, wear resistance and tear resistance of rubber can be significantly improved. However, although silica with a high specific surface area has a stronger reinforcement effect, its dispersion performance is often weakened due to particle agglomeration, which affects the actual application effect. The existing silica preparation technology requires precise control of process parameters: pH value, temperature and dripping speed to ensure uniform particle size distribution and controllable surface activity, thereby maximizing its reinforcement performance. However, it is difficult to achieve precise coordination of process parameters during dynamic changes, which can easily lead to problems such as particle agglomeration and uneven particle size distribution. These problems not only reduce the dispersion performance of silica in the rubber matrix, but also weaken the interfacial bonding force between rubber molecules and silica, making it difficult to give full play to its optimal reinforcement performance. Therefore, further optimizing the preparation process and surface modification technology is the key to improving the comprehensive performance of silica.

[0003] This experimental team has been browsing and studying a large number of relevant records and materials on the relevant technologies for the preparation of silicon dioxide for a long time. At the same time, it relies on relevant resources and conducts a large number of relevant experiments. After a large number of searches, it is found that the existing prior art such as CN114368760A, CN111960427B, CN116969476B, and CN1422805A disclosed in the prior art, such as a highly reinforced and highly dispersed silicon dioxide and its preparation method disclosed in the prior art, specifically discloses the preparation method as follows: mixing water glass solution and sulfuric acid to obtain a first reaction liquid, adding sulfuric acid to the first reaction liquid at a first drop speed, and at the same time adding water glass solution to obtain a second reaction liquid, adding sulfuric acid to the second reaction liquid at a second drop speed, and at the same time adding water glass solution to obtain a fourth reaction liquid, adjusting the pH to obtain a precipitated silicon dioxide suspension, and drying to obtain silicon dioxide. The specific surface area and dispersibility are improved by controlling the drop speed and reaction conditions, but the complexity of the process increases, and the dynamic conditions are difficult to accurately control, resulting in insufficient uniformity of particle size distribution and surface activity during the preparation process.

[0004] The present invention is made to solve the problems commonly existing in the art such as the uneven distribution of silica particle size and limited dispersion performance caused by insufficient control during the preparation process. Summary of the invention

[0005] The purpose of the present invention is to propose a preparation system of highly dispersed silicon dioxide in view of the shortcomings existing in the current art.

[0006] In order to overcome the shortcomings of the prior art, the present invention adopts the following technical solutions:

[0007] A preparation system for highly dispersed silicon dioxide, comprising a preliminary mixing module, a cleaning module and a drying module;

[0008] A preliminary mixing module is used to mix a sodium silicate solution with a concentration of 15-35% and a mixed acid to a pH of 4-5.5, and to mix the mixed solution at 60-65° C. to obtain a mixed solution;

[0009] A cleaning module is used to repeatedly wash the precipitate in the mixed solution and filter it to obtain a filter cake;

[0010] and a drying module, dehydrating the filter cake in an environment of 25-60° C. until it is dry to obtain silicon dioxide powder;

[0011] Wherein, the mixed acid is formic acid, acetic acid, propionic acid, a first composite acid, a second composite acid or a third composite acid, wherein the first composite acid is obtained by mixing formic acid and acetic acid at a molar ratio of 0.5:1-1:0.3, the second composite acid is obtained by mixing formic acid and hydrochloric acid at a molar ratio of 1:1.0-10:1; the third composite acid is obtained by mixing formic acid and sulfuric acid at a molar ratio of 1:1-8:1, and the fourth composite acid is obtained by mixing acetic acid and hydrochloric acid at a molar ratio of 1:1-5:1 or by mixing acetic acid and sulfuric acid at a molar ratio of 1:1-5:1.

[0012] Further, the preliminary mixing module includes a mixing tank for storing the mixed liquid, a heater for heating the mixed liquid in the mixing tank, a temperature sensor for monitoring the temperature of the mixed liquid in the mixing tank, a stirring device for stirring the mixed liquid in the mixing tank, a first quantitative liquid feeder for adding mixed acid to the mixing tank, a liquid level sensor for monitoring the liquid level of the mixed liquid in the mixing tank, a consistency sensor for monitoring the viscosity of the mixed liquid in the mixing tank, a pH detector, a plurality of ultrasonic generators laid on the outer wall of the mixing tank, a sampling unit for sampling the mixed liquid matched with the side wall of the mixing tank, a driving component and a control unit for driving the pH detector to monitor the pH of the sampled mixed liquid in the sampling unit,

[0013] The control unit receives the operating conditions of the heater, the temperature sensor, the first quantitative liquid inlet unit, the pH detector, the ultrasonic generator, the electric control valve, and the drive assembly, and the control unit controls the operation of the heater, the temperature sensor, the first quantitative liquid inlet unit, the pH detector, the ultrasonic generator, the electric control valve, and the drive assembly.

[0014] Furthermore, the mixing tank includes a tank body, a feed port arranged at the top of the tank body, a discharge port arranged at the bottom of the tank body, an electrically controlled valve for controlling the closing of the discharge port, a plurality of discharge ports respectively arranged on the side walls of the tank body, and a sampling port arranged on the side walls of the tank body and correspondingly located above the discharge ports.

[0015] Furthermore, the cleaning module includes a second quantitative liquid inlet for conveying the aqueous solution in the mixing tank, an interception component located in the tank body and arranged in sequence near the drain port, drain pipes respectively connected to the drain ports, an electric valve for controlling the connection between the drain pipe and the drain port, and a drain pump for driving the cleaning liquid in the mixing tank to be discharged from the drain pipe to the outside of the mixing tank, and the interception component includes a closed ring fixed to the inner tank wall of the tank body by welding and a filter mesh fixed to the closed ring by a slot.

[0016] Furthermore, the sampling unit comprises a sampling dish with an opening structure at the upper end, a connecting pipe connecting the side wall of the sampling dish with the sampling port, and a fixing rod with one end fixed to the side wall of the sampling dish and the other half fixed to the side tank wall.

[0017] The top of the sampling dish is higher than the highest liquid level of the mixing tank to prevent leakage of the sampled mixed liquid, and the bottom of the sampling dish is lower than the lowest liquid level of the mixing tank. The connecting pipe is connected to the bottom of the sampling dish, and one end of the connecting pipe connected to the sampling dish is inclined upward.

[0018] Furthermore, the driving assembly includes a lifting driving seat fixed to the tank top wall of the tank body through a mounting seat, a support rod horizontally fixed to the top of the lifting driving seat, and a plurality of fixing rings fixed to the ends of the support rods for sleeve-mounting and fixing to the outer wall of the shell of the pH detector, and the ends of the support rods are correspondingly located above the upper end opening of the sampling dish.

[0019] When the driving assembly moves downward, the probe of the pH detector extends into the upper opening of the sampling dish and further extends below the liquid surface of the sampled mixed liquid, thereby monitoring the pH of the sampled mixed liquid.

[0020] Furthermore, the control unit implements the following operation steps:

[0021] S101: Receive a sodium silicate solution with a concentration of 15-35% from the receiving port, control the heater to heat the sodium silicate solution in the mixing tank to 60-65°C, and maintain the temperature at 60-65°C, drive the first quantitative liquid inlet unit to flow at a preset initial flow rate Fin first Drive the mixed acid into the mixing tank and control the stirring equipment to the initial stirring speed VP first Stirring the mixed liquid in the mixing tank;

[0022] S102: The driving component controls the pH detector to move downward, and the probe passes through the upper opening of the sampling dish and extends below the liquid surface of the sample liquid to ensure that the pH value measured by the pH detector is consistent with the pH value of the mixed liquid in the mixing tank. The pH detector detects the pH value of the sample liquid in real time. current ;

[0023] S103: When the pH is in the warning range [pHa-pHb], adjust the stirring speed of the stirring equipment to VP according to the current viscosity and liquid level. ad :

[0024]

[0025] Wherein, pHa∈[6.0-6.5], pHb∈[7.0-9.0], μmax is the average viscosity of the mixed liquid obtained through historical experience data, μcurrent is the real-time concentration of the current mixed liquid in the mixing tank monitored by the consistency sensor, Hmax is the upper limit of the liquid level of the mixing tank under safe operation, Hliquid is the real-time liquid level of the current mixed liquid in the mixing tank monitored by the liquid level sensor, k1 is the first speed correction coefficient related to the viscosity of the mixed liquid, and k2 is the second speed correction coefficient related to the liquid level of the mixed liquid;

[0026] S104: When the pH is in the target range [pHc-pHd], enter steady-state monitoring, wherein pHc∈[4.5-5.0], pHd∈[5.5-5.8], and the steady-state monitoring implements the following steps:

[0027] S1041: Control equipment to maintain stirring speed VP ad Ensure that the mixed liquid is stirred, and the stirring time is tmixt, tmixt∈[5 seconds, 25 seconds];

[0028] S1042: After the stirring is completed, read the real-time monitoring value of pH current ;

[0029] S1043: If pH current When the pH is greater than the target range, the first liquid inlet device is driven to drip YSD amount of mixed acid into the buffer solution, and s1041-s1042 are repeated until the pH current Once you reach the target range,

[0030] in,

[0031] pH acid is the pH value of the mixed acid, pH target =5.0, Er is the diffusion reference value, e is the natural base, and Rt is the initial calibration amount;

[0032] If pH current When it is within the target range, the operation of the first liquid inlet device is terminated.

[0033] The beneficial effects achieved by the present invention are:

[0034] 1. The real-time connection between the sampling dish and the mixing tank of the present invention ensures that the sampling state is consistent with the mixed liquid in the mixing tank, provides accurate test samples, and avoids reaction deviation caused by sampling errors.

[0035] 2. The present invention ensures that the pH detector obtains the dynamic state of the mixed liquid in real time and ensures that the mixed liquid is always within the target pH range through the precise design of the sampling unit and the driving component, thereby optimizing the formation reaction of silica, improving the preparation efficiency, product purity and dispersion performance of silica, while reducing process errors and manual intervention, and meeting the needs of industrial production of high-performance silica.

[0036] 3. The present invention realizes efficient and accurate mixing and titration control by real-time monitoring of the pH value, viscosity and liquid level of the mixed solution, dynamically adjusting the stirring speed and the acid solution titration amount, and optimizing the process flow to effectively avoid the agglomeration of silica, significantly improve its specific surface area and dispersion performance, and enhance the reinforcement effect of the product. At the same time, parameter optimization and automatic control improve the stability and adaptability of the system, meet different process requirements, reduce manual intervention, and improve the preparation efficiency and consistency of silica. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present invention can be further understood from the following description in conjunction with the accompanying drawings. The components in the figures are not necessarily drawn to scale, but the emphasis is placed on illustrating the principles of the embodiments. In different views, the same reference numerals designate corresponding parts.

[0038] Figure 1 It is a modular schematic diagram of the preparation system of highly dispersed silicon dioxide of the present invention.

[0039] Figure 2 It is a partial structural schematic diagram of the preparation system of highly dispersed silicon dioxide of the present invention.

[0040] Figure 3 It is a schematic diagram of the flow chart of the control unit of the present invention.

[0041] Explanation of the accompanying figures: 1- stirring device; 2- feed inlet; 3- discharge pipe; 4- interception component; 5- discharge port; 6- connecting pipe; 7- fixing rod; 8- sampling dish; 9- pH detector; 10- fixing ring; 11- supporting rod; 12- lifting drive seat; 13- mixing tank. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention is further described in detail in combination with its embodiments below; it should be pointed out that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present case. For those skilled in the art, after reviewing the following detailed description, other systems, methods and / or features of this embodiment will become apparent. And the terms describing the positional relationship in the accompanying drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0043] Embodiment 1: Combining with the attached Figure 1 , Attachment Figure 2 and attached Figure 3 This embodiment constructs a preparation system for highly dispersed silicon dioxide, and the preparation system for highly dispersed silicon dioxide includes a preliminary mixing module, a cleaning module and a drying module, wherein the preliminary mixing module is used to mix a sodium silicate solution with a concentration of 15-35% and a mixed acid to a pH of 4-5.5, and mix the mixed solution at 60-65°C to obtain a mixed solution, the cleaning module is used to repeatedly rinse the precipitate in the mixed solution and filter to obtain a filter cake, and the drying module is used to dehydrate the filter cake in an environment of 25-60°C to dryness to obtain silicon dioxide powder.

[0044] Wherein, the mixed acid is formic acid, acetic acid, propionic acid, a first composite acid, a second composite acid or a third composite acid, wherein the first composite acid is obtained by mixing formic acid and acetic acid at a molar ratio of 0.5:1-1:0.3, the second composite acid is obtained by mixing formic acid and hydrochloric acid at a molar ratio of 1:1.0-10:1; the third composite acid is obtained by mixing formic acid and sulfuric acid at a molar ratio of 1:1-8:1, and the fourth composite acid is obtained by mixing acetic acid and hydrochloric acid at a molar ratio of 1:1-5:1 or by mixing acetic acid and sulfuric acid at a molar ratio of 1:1-5:1.

[0045] The preliminary mixing module includes a mixing tank for storing the mixed liquid, a heater for heating the mixed liquid in the mixing tank, a temperature sensor for monitoring the temperature of the mixed liquid in the mixing tank, a stirring device for stirring the mixed liquid in the mixing tank, a first quantitative liquid feeder for adding mixed acid to the mixing tank, a liquid level sensor for monitoring the liquid level of the mixed liquid in the mixing tank, a consistency sensor for monitoring the viscosity of the mixed liquid in the mixing tank, a pH detector, a plurality of ultrasonic generators laid on the outer wall of the mixing tank, a sampling unit for sampling the mixed liquid coordinated with the side wall of the mixing tank, and a driving component and a control unit for driving the pH detector to monitor the pH of the sampled mixed liquid in the sampling unit.

[0046] The control unit receives the operating conditions of the heater, the temperature sensor, the first quantitative liquid inlet unit, the pH detector, the ultrasonic generator, the electric control valve, and the drive assembly, and the control unit controls the operation of the heater, the temperature sensor, the first quantitative liquid inlet unit, the pH detector, the ultrasonic generator, the electric control valve, and the drive assembly.

[0047] The mixing tank includes a tank body, a feed port arranged at the top of the tank body, a discharge port arranged at the bottom of the tank body, an electrically controlled valve for controlling the closing of the discharge port, a plurality of discharge ports respectively arranged on the side walls of the tank body, and a sampling port arranged on the side walls of the tank body and correspondingly located above the discharge ports.

[0048] The heater forms an annular jacket and is fixedly connected to the outer wall of the tank body by welding or flange, thereby heating the tank body. The stirring device is a stirring device of the prior art, and the rotation speed of the stirring device is transmitted to the control unit in real time. The pH detector feeds back the monitored pH value to the control unit in real time.

[0049] The cleaning module includes a second quantitative liquid inlet for conveying the aqueous solution in the mixing tank, an interception component located in the tank body and arranged in sequence near the discharge port, a discharge pipe connected to the discharge port, an electric valve for controlling the connection between the discharge pipe and the discharge port, and a discharge pump for driving the cleaning liquid in the mixing tank to be discharged from the discharge pipe to the outside of the mixing tank.

[0050] The interception component is used for solid-liquid separation during the discharge of the cleaning liquid, preventing the sediment in the tank body from entering the drain pipe and causing blockage while ensuring that the cleaning liquid flows out from the drain port. The interception component includes a closed ring fixed to the inner tank wall of the tank body by welding and a filter sheet fixed to the closed ring by a slot.

[0051] The inner edge of the closed ring is provided with several slots, and the edge of the slot is provided with an anti-slip buckle structure to improve the fixing strength of the filter and prevent the filter from loosening and falling off during operation. The outer edge of the filter is provided with an embedded flange that is compatible with the slot structure, so that the filter can be tightly inserted into the slot.

[0052] The sampling unit comprises a sampling dish with an opening structure at the upper end, a connecting pipe connecting the side wall of the sampling dish with the sampling port, and a fixing rod with one end fixed to the side wall of the sampling dish and the other half fixed to the side tank wall.

[0053] Among them, the top of the sampling dish is higher than the highest liquid level of the mixing tank to prevent the sampled mixed liquid from leaking. At the same time, the bottom of the sampling dish is lower than the lowest liquid level of the mixing tank, ensuring that the sampled mixed liquid is connected with the mixed liquid in the tank in real time and dynamically updated, thereby ensuring the synchronization of the sampling liquid and the mixed liquid, and providing accurate and dynamic samples for real-time detection. Through the real-time connection design between the sampling dish and the mixing tank, the liquid in the sampling dish can dynamically reflect the changes in the state of the mixed liquid, providing accurate and real-time detection conditions for pH monitoring.

[0054] The connecting tube is connected to the bottom of the sampling dish, and the end of the connecting tube connected to the sampling dish is tilted upward accordingly. The connecting tube uses gravity to assist the natural flow of the liquid through the inclined design, ensuring that the mixed liquid can stably enter the sampling dish, avoiding turbulence or sediment accumulation caused by the outlet position being too low, and preventing the liquid from being retained in the connecting tube. It not only realizes the efficient renewal of the sampling liquid, but also ensures the smoothness of the liquid flow, providing reliable support for the liquid in the sampling dish to dynamically reflect the changes in the liquid state in the mixing tank, and laying the foundation for accurate real-time detection.

[0055] The driving assembly includes a lifting driving seat fixed to the top wall of the tank body through a mounting seat, a support rod horizontally fixed to the top of the lifting driving seat, and a plurality of fixing rings fixed to the ends of the support rods for being sleeved and fixed to the outer wall of the shell of the pH detector. At the same time, the ends of the support rods are correspondingly located above the upper opening of the sampling dish, and the drying module is realized by the vacuum dryer of the prior art, which will not be repeated here.

[0056] When the driving assembly moves downward, the probe of the pH detector is inserted into the upper opening of the sampling dish and further extends below the liquid surface of the sampled mixed liquid to monitor the pH of the sampled mixed liquid. The driving assembly can smoothly adjust the position of the pH detector through the coordinated design of the lifting drive seat, the support rod and the fixed ring, ensuring that the probe of the pH detector is accurately inserted into the sampling dish to monitor the liquid in real time, thereby ensuring the reliability of the detection data and meeting the needs of efficient industrial monitoring.

[0057] The present invention ensures that the pH detector obtains the dynamic state of the mixed liquid in real time and ensures that the mixed liquid is always within the target pH range through the precise design of the sampling unit and the driving component, thereby optimizing the formation reaction of silicon dioxide, improving the preparation efficiency, product purity and dispersion performance of silicon dioxide, and reducing process errors and manual intervention, thereby meeting the needs of industrial production of high-performance silicon dioxide.

[0058] Embodiment 2: Combining with Figure 1 , Attachment Figure 2 and attached Figure 3 In addition to the contents of the above embodiments, the control unit also implements the following operation steps:

[0059] S101: Receive a sodium silicate solution with a concentration of 15-35% from the receiving port, control the heater to heat the sodium silicate solution in the mixing tank to 60-65°C, and maintain the temperature at 60-65°C, drive the first quantitative liquid inlet unit to flow at a preset initial flow rate Fin first Drive the mixed acid into the mixing tank and control the stirring equipment to the initial stirring speed VP first The mixed liquid in the mixing tank is stirred, wherein the initial flow rate Fin first and initial stirring speed VP first VP is predetermined by those skilled in the art based on historical experience and experimental training in the field. first ∈[150 rpm-250 rpm];

[0060] S102: The driving component controls the pH detector to move downward, and the probe passes through the upper opening of the sampling dish and extends below the liquid surface of the sample liquid to ensure that the pH value measured by the pH detector is consistent with the pH value of the mixed liquid in the mixing tank. The pH detector detects the pH value of the sample liquid in real time. current ;

[0061] S103: When the pH is in the warning range [pHa-pHb], adjust the stirring speed of the stirring equipment to VP according to the current viscosity and liquid level. ad :

[0062]

[0063] Wherein, pHa∈[6.0-6.5], pHb∈[7.0-9.0], μmax is the average viscosity of the mixed liquid obtained through historical experience data, μcurrent is the real-time concentration of the current mixed liquid in the mixing tank monitored by the consistency sensor, Hmax is the upper limit of the liquid level of the mixing tank under safe operation, Hliquid is the real-time liquid level of the current mixed liquid in the mixing tank monitored by the liquid level sensor, k1 is the first speed correction coefficient related to the viscosity of the mixed liquid, k2 is the second speed correction coefficient related to the liquid level of the mixed liquid,

[0064] Among them, k1 and k2 are based on historical operation data analysis and experimental calibration results, and are adjusted according to the influence of each index on the mixing efficiency of the mixed liquid in combination with actual working conditions. Through numerical simulation and multi-dimensional optimization algorithm, k1 and k2 are rationalized and optimized in the case that the pH of the mixed liquid is within the warning range, and the contribution ratio of viscosity and liquid level to the mixing and uniform distribution effect of the mixed liquid is obtained, so as to obtain the final values ​​of k1 and k2;

[0065] S104: When the pH is in the target range [pHc-pHd], enter steady-state monitoring, wherein pHc∈[4.5-5.0], pHd∈[5.5-5.8], and the steady-state monitoring implements the following steps:

[0066] S1041: Control equipment to maintain stirring speed VP ad Ensure that the mixed liquid is stirred, and the stirring time is tmixt, tmixt∈[5 seconds, 25 seconds];

[0067] S1042: After the stirring is completed, read the real-time monitoring value of pH current ;

[0068] S1043: If pH current When the pH is greater than the target range, the first liquid inlet device is driven to drip YSD amount of mixed acid into the buffer solution, and s1041-s1042 are repeated until the pH current Once you reach the target range,

[0069] If pH current When it is within the target range, the operation of the first liquid inlet device is terminated.

[0070] in,

[0071] pH acid is the pH value of the mixed acid, pH target =5.0, Er is the diffusion reference value, e is the natural base, and Er is the value determined by technicians in this field based on historical experience data for VP ad ×tmix is ​​a reference value for standardization, and Rt is an initial calibration amount set by a technician in this field according to the actual capacity of the mixing tank.

[0072] β is the initial value set by technicians in this field based on their rich practical experience, and is iteratively optimized through multiple experiments and practical application feedback to comprehensively reflect pH. acid , pH current VP ad The mutual influence between tmix and titration YSD is ensured by analyzing the experimental data obtained from repeated test training and optimizing the correlation modeling between variables to ensure that β can accurately correct the titration of mixed acids in the steady-state monitoring process, thereby improving the accuracy and stability of the titration of the mixed solution, so as to ensure the accuracy of the final value of the titration of the mixed solution.

[0073] In this embodiment, those skilled in the art can refer to the above value examples and make adjustments according to actual conditions. In short, the specific value ranges and trends of K1, K2, pHa, pHb, pHc, pHd, β, Er, tmix, and Rt will be determined by the designers or operators of the system according to the actual system requirements and system reactions by those skilled in the art, and will not be repeated here.

[0074] The present invention realizes efficient and accurate mixing and titration control by real-time monitoring of the pH value, viscosity and liquid level of the mixed solution, dynamically adjusting the stirring speed and the acid solution titration amount, and optimizing the process flow to effectively avoid the agglomeration of silicon dioxide, significantly improve its specific surface area and dispersion performance, and enhance the reinforcement effect of the product; at the same time, parameter optimization and automatic control improve the stability and adaptability of the system, meet different process requirements, reduce manual intervention, and improve the preparation efficiency and consistency of silicon dioxide.

[0075] Although the present invention has been described above with reference to various embodiments, it should be understood that many changes and modifications may be made without departing from the scope of the present invention. That is, the methods, systems and devices discussed above are examples. Various configurations may appropriately omit, replace or add various processes or components. For example, in alternative configurations, the method may be performed in an order different from that described, and / or various components may be added, omitted and / or combined. Moreover, the features described with respect to certain configurations may be combined in various other configurations, such as different aspects and elements of the configuration may be combined in a similar manner. In addition, as technology develops, the elements therein may be updated, i.e., many elements are examples and do not limit the scope of the present disclosure or claims. And it should be understood that after reading the contents of the record of the present invention, the technician may make various changes or modifications to the present invention, and these equivalent changes and modifications also fall within the scope defined by the claims of the present invention.

Claims

1. A system for preparing highly dispersed silicon dioxide, characterized in that: The highly dispersed silicon dioxide preparation system comprises a preliminary mixing module, a cleaning module and a drying module; A preliminary mixing module is used to mix a sodium silicate solution with a concentration of 15-35% and a mixed acid to a pH of 4-5.5, and to mix the mixed solution at 60-65° C. to obtain a mixed solution; A cleaning module is used to repeatedly wash the precipitate in the mixed solution and filter it to obtain a filter cake; and a drying module, dehydrating the filter cake in an environment of 25-60° C. until it is dry to obtain silicon dioxide powder; Wherein, the mixed acid is formic acid, acetic acid, propionic acid, a first composite acid, a second composite acid or a third composite acid, wherein the first composite acid is obtained by mixing formic acid and acetic acid at a molar ratio of 0.5:1-1:0.3, the second composite acid is obtained by mixing formic acid and hydrochloric acid at a molar ratio of 1:1.0-10:1; the third composite acid is obtained by mixing formic acid and sulfuric acid at a molar ratio of 1:1-8:1, and the fourth composite acid is obtained by mixing acetic acid and hydrochloric acid at a molar ratio of 1:1-5:1 or by mixing acetic acid and sulfuric acid at a molar ratio of 1:1-5:

1.

2. The preparation system according to claim 1, characterized in that: The preliminary mixing module includes a mixing tank for storing the mixed liquid, a heater for heating the mixed liquid in the mixing tank, a temperature sensor for monitoring the temperature of the mixed liquid in the mixing tank, a stirring device for stirring the mixed liquid in the mixing tank, a first quantitative liquid feeder for adding mixed acid to the mixing tank, a liquid level sensor for monitoring the liquid level of the mixed liquid in the mixing tank, a consistency sensor for monitoring the viscosity of the mixed liquid in the mixing tank, a pH detector, a plurality of ultrasonic generators laid on the outer wall of the mixing tank, a sampling unit for sampling the mixed liquid matched with the side wall of the mixing tank, a driving component and a control unit for driving the pH detector to monitor the pH of the sampled mixed liquid in the sampling unit, The control unit receives the operating conditions of the heater, the temperature sensor, the first quantitative liquid inlet unit, the pH detector, the ultrasonic generator, the electric control valve, and the drive assembly, and the control unit controls the operation of the heater, the temperature sensor, the first quantitative liquid inlet unit, the pH detector, the ultrasonic generator, the electric control valve, and the drive assembly.

3. The preparation system according to claim 2, characterized in that: The mixing tank includes a tank body, a feed port arranged at the top of the tank body, a discharge port arranged at the bottom of the tank body, an electrically controlled valve for controlling the closing of the discharge port, a plurality of discharge ports respectively arranged on the side walls of the tank body, and a sampling port arranged on the side walls of the tank body and correspondingly located above the discharge ports.

4. The preparation system according to claim 3, characterized in that: The cleaning module includes a second quantitative liquid inlet for conveying aqueous solution in the mixing tank, an interception component located in the tank body and arranged in sequence near the discharge port, discharge pipes respectively connected to the discharge ports, an electric valve for controlling the connection between the discharge pipe and the discharge port, and a discharge pump for driving the cleaning liquid in the mixing tank to be discharged from the discharge pipe to the outside of the mixing tank. The interception component includes a closed ring fixed to the inner tank wall of the tank body by welding and a filter mesh fixed to the closed ring by a slot.

5. The preparation system according to claim 4, characterized in that: The sampling unit comprises a sampling dish with an opening structure at the upper end, a connecting pipe connecting the side wall of the sampling dish with the sampling port, and a fixing rod with one end fixed to the side wall of the sampling dish and the other half fixed to the side tank wall. Among them, the top of the sampling dish is higher than the highest liquid level of the mixing tank to prevent the sampled mixed liquid from leaking. At the same time, the bottom of the sampling dish is lower than the lowest liquid level of the mixing tank. The connecting tube is connected to the bottom of the sampling dish, and the end of the connecting tube connected to the sampling dish is correspondingly tilted upward.

6. The preparation system according to claim 5, characterized in that: The driving assembly includes a lifting driving seat fixed to the tank top wall of the tank body through a mounting seat, a support rod horizontally fixed to the top of the lifting driving seat, and a plurality of fixing rings fixed to the ends of the support rods for sleeve-mounting and fixing to the outer wall of the shell of the pH detector, and the ends of the support rods are correspondingly located above the upper end opening of the sampling dish. When the driving assembly moves downward, the probe of the pH detector extends into the upper opening of the sampling dish and further extends below the liquid surface of the sampled mixed liquid, thereby monitoring the pH of the sampled mixed liquid.

7. The preparation system according to claim 6, characterized in that: The control unit implements the following operating steps: S101: Receive a sodium silicate solution with a concentration of 15-35% from the receiving port, control the heater to heat the sodium silicate solution in the mixing tank to 60-65°C, and maintain the temperature at 60-65°C, drive the first quantitative liquid inlet unit to flow at a preset initial flow rate Fin first Drive the mixed acid into the mixing tank and control the stirring equipment to the initial stirring speed VP first Stirring the mixed liquid in the mixing tank; S102: The driving component controls the pH detector to move downward, and the probe passes through the upper opening of the sampling dish and extends below the liquid surface of the sample liquid to ensure that the pH value measured by the pH detector is consistent with the pH value of the mixed liquid in the mixing tank. The pH detector detects the pH value of the sample liquid in real time. current ; S103: When the pH is in the warning range [pHa-pHb], adjust the stirring speed of the stirring equipment to VP according to the current viscosity and liquid level. ad : Wherein, pHa∈[6.0-6.5], pHb∈[7.0-9.0], μmax is the average viscosity of the mixed liquid obtained through historical experience data, μcurrent is the real-time concentration of the current mixed liquid in the mixing tank monitored by the consistency sensor, Hmax is the upper limit of the liquid level of the mixing tank under safe operation, Hliquid is the real-time liquid level of the current mixed liquid in the mixing tank monitored by the liquid level sensor, k1 is the first speed correction coefficient related to the viscosity of the mixed liquid, and k2 is the second speed correction coefficient related to the liquid level of the mixed liquid; S104: When the pH is in the target range [pHc-pHd], enter steady-state monitoring, wherein pHc∈[4.5-5.0], pHd∈[5.5-5.8], and the steady-state monitoring implements the following steps: S1041: Control equipment to maintain stirring speed VP ad Ensure that the mixed liquid is stirred, and the stirring time is tmixt, tmixt∈[5 seconds, 25 seconds]; S1042: After the stirring is completed, read the real-time monitoring value of pH current ; S1043: If pH current When the pH is greater than the target range, the first liquid inlet device is driven to drip YSD amount of mixed acid into the buffer solution, and s1041-s1042 are repeated until the pH current Once you reach the target range, in, pH acid is the pH value of the mixed acid, pH target =5.0, Er is the diffusion reference value, e is the natural base, and Rt is the initial calibration amount; If pH current When it is within the target range, the operation of the first liquid inlet device is terminated.

Images