Preparation method of precipitated silicon dioxide for low-wear conveying belt

Abstract

The invention discloses a preparation method of precipitated silica for a low-wear conveyor belt, belonging to the technical field of silica preparation, comprising the following steps: adding ethyl 3-ethoxypropionate into a reactor, and using the ethyl 3-ethoxypropionate as a solvent of the whole reaction system; arachidic acid and a solvent are added into the reactor and stirred for 5 min, the stirring speed at the beginning is 100 r / min-150 r / min, the stirring speed is gradually increased to 200 r / min-250 r / min after stirring is conducted for 1 min-2 min, and finally the stirring speed is kept at 300 r / min-350 r / min after stirring is completed for 5 min; the arachidic acid can be prepared by hydrolyzing and separating peanut oil, the arachidic acid is C20 acid, is small in acidic side effect and high in purity, has oxidation resistance, can improve the thermo-oxidative aging resistance and corrosion resistance of rubber products, and meanwhile, as a sustainable substitute, an environment-friendly ester product will become a mainstream in the future. The method is not only environment-friendly, but also can promote sustainable development of economy and society.

Description

Technical Field

[0001] The invention belongs to the technical field of silicon dioxide preparation, and in particular relates to a method for preparing silicon dioxide for low-wear conveyor belts using a precipitation method. Background Art

[0002] Conveyor belts are composite products made of rubber, fiber, metal, or plastic and fabric that carry and transport materials. They are widely used in industries such as cement, coking, metallurgy, chemical, and steel.

[0003] In the production process of rubber conveyor belts

[0004] In the production of rubber conveyor belts, silica, as a key additive, plays a significant role in improving the belt's performance. Silica's primary role in rubber conveyor belts is in improving wear resistance. Conveyor belts are subject to significant friction and wear during operation, and silica, as an excellent wear-resistant material, can effectively reduce the wear rate of conveyor belts, extending their service life. Silica also improves the conveyor belt's tear resistance, enhancing its structural stability and reliability. Conveyor belts are prone to deformation and shrinkage in high-temperature environments, and silica effectively reduces these phenomena, ensuring the belt's stability and reliability in these conditions. Furthermore, silica, when used in combination with other conductive fillers, can improve the rubber conveyor belt's electrical conductivity, reduce static electricity accumulation during operation, and mitigate safety hazards caused by static electricity. Silica also improves the conveyor belt's antioxidant properties, slowing its aging rate and maintaining its long-term stable performance. To this end, we propose a method for preparing precipitated silica for low-wear conveyor belts. Summary of the Invention

[0005] The present invention provides a method for preparing precipitated silica for low-wear conveyor belts to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for preparing precipitated silica for low-wear conveyor belts, comprising the following steps:

[0007] S1. Select solid sodium silicate with a modulus of 3.0-3.3 and prepare a water glass solution with a concentration of 15wt% to 25wt% for standby use;

[0008] The sulfuric acid solution is selected to have a concentration of 98 wt% for standby use;

[0009] During the reaction, disodium lauryl sulfosuccinate was added as a reaction dispersant in an amount of 0.5% of the mass of silica;

[0010] S2. Add 1 / 6 of the volume of industrial water as bottom water to the reactor, add the prepared water glass solution, accurately control the amount of the water glass solution added by a metering pump, add the water glass solution to the reactor in a dropwise manner, and add sodium sulfate as a reaction electrolyte. Set the reaction temperature to 70°C to 80°C and the stirring rate to 80 / min to 100 r / min;

[0011] S3. At the set temperature and stirring rate, sodium silicate solution and sulfuric acid solution are added simultaneously, and the reaction pH is controlled in the range of 9.0 to 10.0 until the volume of the reaction system reaches 40% of the reactor, and the reaction time is 60 min;

[0012] S4, maintaining the stirring rate unchanged, raising the reaction temperature to 80°C to 100°C, continuing to add the sodium silicate solution and the sulfuric acid solution, and maintaining the pH value of the reaction system in the range of 9.0 to 10.0 until the volume of the reaction system reaches 70% of the reactor, and the reaction time is 60 min;

[0013] S5. Continue to add sulfuric acid solution, adjust the pH value of the reaction system to 5.0, stop adding acid, and continue aging the reaction system for 30 minutes. Keep stirring during the aging process at a stirring rate of 50 r / min to 60 r / min. The reaction is completed;

[0014] S6, preparing a concentrated slurry by filtering, washing, and beating the reaction slurry obtained in step S5;

[0015] Filtration: The reaction slurry obtained in step S5 is transported to a filter press through a pipeline for filtration;

[0016] Washing: Wash the filter cake after filtration using deionized water for 4 to 5 times;

[0017] Beating: Beat the washed filter cake and add sodium polyacrylate as a dispersant during the beating process;

[0018] S7, drying and granulating the concentrated slurry obtained in step S6 to obtain the target product silica particles;

[0019] Drying: The concentrated slurry obtained in step S6 is sent to a spray dryer for drying using hot air generated by a natural gas burner;

[0020] Granulation: The dried powdered product is put into a granulator for granulation, and a disc granulator is used for granulation. During the granulation process, sodium carboxymethyl cellulose is added as a binder. After the granulation is completed, the particles are sieved using a sieve to obtain the target product, silica particles.

[0021] Furthermore, in step S1, when selecting solid sodium silicate, a 20-60 mesh sieve is used to screen solid sodium silicate with uniform particle size;

[0022] Preparation of water glass solution: slowly add the screened solid sodium silicate into industrial water. During the addition process, the stirring speed is 200r / min~300r / min, and the temperature is controlled at 20℃~30℃;

[0023] Sulfuric acid solution: Before use, the sulfuric acid solution needs to be preheated through a heat exchanger and the preheating temperature should be set at 40℃~50℃;

[0024] Reaction dispersant: Disodium lauryl sulfosuccinate is dissolved in deionized water before use to prepare a 10wt% to 15wt% solution. During the dissolution process, a magnetic stirrer is used to stir at a speed of 300r / min to 500r / min for 10min to 15min to ensure that the dispersant is completely dissolved.

[0025] Furthermore, in step S2, before using industrial water as bottom water, the reactor is first cleaned and dried, heated using a jacketed heating device, and stirred using an anchor stirrer;

[0026] When adding the prepared water glass solution, the drop rate is controlled at 1mL / s to 2mL / s;

[0027] Sodium sulfate is added as a reaction electrolyte. The amount of sodium sulfate added is accurately calculated based on the volume of the reactor and the requirements of the reaction system, and is generally 1 to 1.5 times the amount of silicon dioxide in the water glass solution.

[0028] Furthermore, in step S3, the sodium silicate solution and the sulfuric acid solution are added to the reactor using a multi-point nozzle method so that the solutions can be fully mixed and reacted in the reactor. The pH meter should be calibrated regularly, with a calibration period of every 20 to 30 minutes.

[0029] Furthermore, in step S4, the temperature is gradually increased from 80°C to 90°C to 100°C, and the heating rate is controlled at 12°C / min to 2°C / min.

[0030] Data collection was performed every 1 to 2 minutes and recorded.

[0031] Furthermore, in step S6, the amount of water used for each washing is 2 to 3 times the mass of the filter cake, and the filtrate after washing is tested. When the sulfate ion concentration in the filtrate is lower than 0.1 mol / L, the washing is considered qualified;

[0032] The pressure of the filter press is controlled at 0.3MPa to 0.5MPa, and the beating is performed using a high-speed disperser with a rotation speed of 1000r / min to 1500r / min, and the beating time is 15min to 20min.

[0033] Furthermore, in step S7, the air inlet temperature of the spray dryer is controlled at 200°C to 300°C, and the air outlet temperature is controlled at 100°C to 120°C;

[0034] The particle size is selected within the range of 0.5mm to 2mm.

[0035] The beneficial effects of the present invention are:

[0036] 1. The present invention explicitly selects solid sodium silicate with a modulus of 3.0 to 3.3 and specifies a concentration range of the water glass solution, which helps to accurately control the initial conditions of the reaction, is conducive to the formation of white carbon black with good properties, and may improve the purity and crystallinity of the product.

[0037] 2. The present invention adjusts the aggregate structure, improves the mechanical properties of the rubber compound product, and significantly improves the wear resistance by adding disodium lauryl sulfosuccinate as a dispersant.

[0038] 3. The present invention forms a complete system from the reaction slurry to a series of post-processing processes such as filtration pressing, washing, beating, drying and granulation. Compared with some existing methods with incomplete post-processing steps or loose connections between steps, this consistency helps to retain the excellent performance of the white carbon black product to the greatest extent. Reasonable filtration pressing and washing can effectively remove impurities, beating to prepare concentrated slurry can make the product more uniform, and the reasonable setting of the drying and granulation processes helps to obtain the shape and particle size of silica particles suitable for use in low-wear conveyor belts. DETAILED DESCRIPTION

[0039] In order to further understand the content, features and effects of the present invention, the following embodiments are given as examples and described in detail with reference to the accompanying drawings.

[0040] Example 1:

[0041] A method for preparing precipitated silica for low-wear conveyor belts comprises the following steps:

[0042] The following steps are involved:

[0043] S1. Select solid sodium silicate with a modulus of 3.0. When selecting the solid sodium silicate, use a 20-60 mesh sieve to screen solid sodium silicate with uniform particle size. Slowly add the screened solid sodium silicate to industrial water. During the addition, stir at a speed of 200-300 r / min. Control the temperature at 20° C.-30° C. to obtain a water glass solution with a concentration of 15 wt %. The water glass solution with a concentration of 15 wt % is set aside.

[0044] The sulfuric acid solution is prepared with a concentration of 90 wt %, and the sulfuric acid solution needs to be preheated by a heat exchanger before use, and the preheating temperature is set at 40°C to 50°C;

[0045] During the reaction, disodium lauryl sulfosuccinate is added as a reaction dispersant in an amount of 0.5% of the mass of the silica. Before use, disodium lauryl sulfosuccinate is dissolved in deionized water to prepare a 10wt% to 15wt% solution. During the dissolution process, a magnetic stirrer is used to stir at a speed of 300r / min to 500r / min for 10min to 15min to ensure that the dispersant is completely dissolved.

[0046] S2. Before using industrial water as bottom water, the reactor is first cleaned and dried, and then 1 / 6 of the volume of industrial water is added to the reactor as bottom water, and the prepared water glass solution is added. The amount of the water glass solution added is accurately controlled by a metering pump, and the water glass solution is added to the reactor in a dropwise manner. The dropwise addition speed is controlled at 1 mL / s to 2 mL / s, and sodium sulfate is added as a reaction electrolyte. The amount of sodium sulfate added is generally 1 to 1.5 times the amount of silica in the water glass solution. When heating, a jacketed heating device is used for heating, and the reaction temperature is set to 70°C. An anchor stirrer is used for stirring at a stirring rate of 80 / min;

[0047] S3. At the set temperature and stirring rate, add the sodium silicate solution and the sulfuric acid solution to the reactor using a multi-point nozzle method to allow the solutions to fully mix and react in the reactor. The reaction pH is controlled within the range of 9.0 until the reaction system volume reaches 40% of the reactor. The reaction time is 60 minutes. During the reaction process, the pH meter should be calibrated regularly at a calibration interval of every 20 to 30 minutes.

[0048] S4. Maintaining the stirring rate unchanged, the reaction temperature was raised to 80°C to 100°C, and the temperature was gradually increased from 80°C to 90°C to 100°C, respectively, with the heating rate controlled at 12°C / min to 2°C / min. The sodium silicate solution and the sulfuric acid solution were continued to be added, and the pH value of the reaction system was maintained in the range of 9.0 to 10.0 until the volume of the reaction system reached 70% of the reactor. The reaction time was 60 min, and data was collected every 1 min to 2 min and recorded once.

[0049] S5. Continue to add sulfuric acid solution, adjust the pH value of the reaction system to 5.0, stop adding acid, and continue aging the reaction system for 30 minutes. Keep stirring during the aging process at a stirring rate of 50 r / min to 60 r / min. The reaction is completed;

[0050] S6, preparing a concentrated slurry by filtering, washing, and beating the reaction slurry obtained in step S5;

[0051] Filtration: The reaction slurry obtained in step S5 is transported to a filter press through a pipeline for filtration, and the pressure of the filter press is controlled at 0.3 MPa;

[0052] Washing: Wash the filter cake after filter pressing with deionized water for 4 to 5 times. The amount of water used for each wash is 2 to 3 times the mass of the filter cake. The filtrate after washing is tested. When the sulfate ion concentration in the filtrate is lower than 0.1 mol / L, it is considered qualified.

[0053] Beating: Beat the washed filter cake, and add sodium polyacrylate as a dispersant during the beating process. The beating is carried out using a high-speed disperser with a speed of 1000r / min and a beating time of 15min.

[0054] S7, drying and granulating the concentrated slurry obtained in step S6 to obtain the target product silica particles;

[0055] Drying: The concentrated slurry obtained in step S6 is fed into a spray dryer for drying using hot air generated by a natural gas burner. The inlet air temperature of the spray dryer is controlled at 200°C to 300°C, and the outlet air temperature is controlled at 100°C to 120°C.

[0056] Granulation: The dried powdered product is put into a granulator for granulation, and a disc granulator is used for granulation. During the granulation process, sodium carboxymethyl cellulose is added as a binder. After the granulation is completed, the particles are sieved with a sieve and the particle size is selected within the range of 0.5 mm to obtain the target product, silica particles.

[0057] Example 2:

[0058] A method for preparing precipitated silica for low-wear conveyor belts comprises the following steps:

[0059] The following steps are involved:

[0060] S1. Select solid sodium silicate with a modulus of 3.2. When selecting the solid sodium silicate, use a 20-60 mesh sieve to screen solid sodium silicate with uniform particle size. Slowly add the screened solid sodium silicate to industrial water. During the addition process, stir at a speed of 200-300 r / min. Control the temperature at 20° C.-30° C. to obtain a water glass solution with a concentration of 20 wt %. The water glass solution with a concentration of 20 wt % is set aside.

[0061] The sulfuric acid solution is prepared with a concentration of 95 wt %, and the sulfuric acid solution needs to be preheated by a heat exchanger before use, and the preheating temperature is set at 40°C to 50°C;

[0062] During the reaction, disodium lauryl sulfosuccinate is added as a reaction dispersant in an amount of 0.5% of the mass of the silica. Before use, disodium lauryl sulfosuccinate is dissolved in deionized water to prepare a 10wt% to 15wt% solution. During the dissolution process, a magnetic stirrer is used to stir at a speed of 300r / min to 500r / min for 10min to 15min to ensure that the dispersant is completely dissolved.

[0063] S2. Before using industrial water as bottom water, the reactor is first cleaned and dried, and then 1 / 6 of the volume of industrial water is added to the reactor as bottom water, and the prepared water glass solution is added. The amount of the water glass solution added is accurately controlled by a metering pump, and the water glass solution is added to the reactor in a dropwise manner. The dropwise addition speed is controlled at 1 mL / s to 2 mL / s, and sodium sulfate is added as a reaction electrolyte. The amount of sodium sulfate added is generally 1 to 1.5 times the amount of silica in the water glass solution. When heating, a jacketed heating device is used for heating, and the reaction temperature is set to 75°C. An anchor stirrer is used for stirring at a stirring rate of 90 r / min;

[0064] S3. At the set temperature and stirring rate, add the sodium silicate solution and the sulfuric acid solution to the reactor using a multi-point nozzle method, so that the solutions can be fully mixed and reacted in the reactor. The reaction pH is controlled within the range of 9.5 until the volume of the reaction system reaches 40% of the reactor. The reaction time is 60 minutes. During the reaction process, the pH meter should be calibrated regularly, with a calibration period of every 20 minutes to 30 minutes.

[0065] S4. Maintaining the stirring rate unchanged, the reaction temperature was raised to 80°C to 100°C, and the temperature was gradually increased from 80°C to 90°C to 100°C, respectively, with the heating rate controlled at 12°C / min to 2°C / min. The sodium silicate solution and the sulfuric acid solution were continued to be added, and the pH value of the reaction system was maintained in the range of 9.0 to 10.0 until the volume of the reaction system reached 70% of the reactor. The reaction time was 60 min, and data was collected every 1 min to 2 min and recorded once.

[0066] S5. Continue to add sulfuric acid solution, adjust the pH value of the reaction system to 5.0, stop adding acid, and continue aging the reaction system for 30 minutes. Keep stirring during the aging process at a stirring rate of 50 r / min to 60 r / min. The reaction is completed;

[0067] S6, preparing a concentrated slurry by filtering, washing, and beating the reaction slurry obtained in step S5;

[0068] Filtration: The reaction slurry obtained in step S5 is transported to a filter press through a pipeline for filtration, and the pressure of the filter press is controlled at 0.35 MPa;

[0069] Washing: Wash the filter cake after filter pressing with deionized water for 4 to 5 times. The amount of water used for each wash is 2 to 3 times the mass of the filter cake. The filtrate after washing is tested. When the sulfate ion concentration in the filtrate is lower than 0.1 mol / L, it is considered qualified.

[0070] Beating: Beat the washed filter cake, and add sodium polyacrylate as a dispersant during the beating process. A high-speed disperser is used for beating, with a speed of 1200 r / min and a beating time of 17 min.

[0071] S7, drying and granulating the concentrated slurry obtained in step S6 to obtain the target product silica particles;

[0072] Drying: The concentrated slurry obtained in step S6 is sent to a spray dryer for drying using hot air generated by a natural gas burner. The inlet air temperature of the spray dryer is controlled at 150°C and the outlet air temperature is controlled at 110°C.

[0073] Granulation: The dried powdered product is put into a granulator for granulation, and a disc granulator is used for granulation. During the granulation process, sodium carboxymethyl cellulose is added as a binder. After the granulation is completed, the particles are sieved with a sieve and the particle size is selected within the range of 1.5 mm to obtain the target product, silica particles.

[0074] Example 3:

[0075] A method for preparing precipitated silica for low-wear conveyor belts comprises the following steps:

[0076] The following steps are involved:

[0077] S1. Select solid sodium silicate with a modulus of 3.3. When selecting the solid sodium silicate, use a 20-60 mesh sieve to screen solid sodium silicate with uniform particle size. Slowly add the screened solid sodium silicate to industrial water. During the addition, stir at a speed of 200-300 r / min. Control the temperature at 20° C.-30° C. to obtain a water glass solution with a concentration of 25 wt%. The water glass solution with a concentration of 25 wt% is set aside.

[0078] The sulfuric acid solution is selected with a concentration of 98wt% for standby use, and the sulfuric acid solution needs to be preheated through a heat exchanger before use, and the preheating temperature is set at 40℃~50℃;

[0079] During the reaction, disodium lauryl sulfosuccinate is added as a reaction dispersant in an amount of 0.5% of the mass of the silica. Before use, disodium lauryl sulfosuccinate is dissolved in deionized water to prepare a 10wt% to 15wt% solution. During the dissolution process, a magnetic stirrer is used to stir at a speed of 300r / min to 500r / min for 10min to 15min to ensure that the dispersant is completely dissolved.

[0080] S2. Before using industrial water as bottom water, the reactor is first cleaned and dried, and then industrial water accounting for 1 / 6 of the volume of the reactor is added as bottom water, and the prepared water glass solution is added. The amount of the water glass solution added is accurately controlled by a metering pump, and the water glass solution is added to the reactor in a dropwise manner. The dropwise addition speed is controlled at 1 mL / s to 2 mL / s, and sodium sulfate is added as a reaction electrolyte. The amount of sodium sulfate added is generally 1 to 1.5 times the amount of silica in the water glass solution. When heating, a jacketed heating device is used for heating, and the reaction temperature is set to 80° C. An anchor stirrer is used for stirring at a stirring rate of 100 r / min;

[0081] S3. At the set temperature and stirring rate, add the sodium silicate solution and the sulfuric acid solution to the reactor using a multi-point nozzle method to allow the solutions to fully mix and react in the reactor. The reaction pH is controlled within the range of 10.0 until the reaction system volume reaches 40% of the reactor. The reaction time is 60 minutes. During the reaction process, the pH meter should be calibrated regularly at a calibration interval of every 20 to 30 minutes.

[0082] S4. Maintaining the stirring rate unchanged, the reaction temperature was raised to 80°C to 100°C, and the temperature was gradually increased from 80°C to 90°C to 100°C, respectively, with the heating rate controlled at 12°C / min to 2°C / min. The sodium silicate solution and the sulfuric acid solution were continued to be added, and the pH value of the reaction system was maintained in the range of 9.0 to 10.0 until the volume of the reaction system reached 70% of the reactor. The reaction time was 60 min, and data was collected every 1 min to 2 min and recorded once.

[0083] S5. Continue to add sulfuric acid solution, adjust the pH value of the reaction system to 5.0, stop adding acid, and continue aging the reaction system for 30 minutes. Keep stirring during the aging process at a stirring rate of 50 r / min to 60 r / min. The reaction is completed;

[0084] S6, preparing a concentrated slurry by filtering, washing, and beating the reaction slurry obtained in step S5;

[0085] Filtration: The reaction slurry obtained in step S5 is transported to a filter press through a pipeline for filtration, and the pressure of the filter press is controlled at 0.5 MPa;

[0086] Washing: Wash the filter cake after filter pressing with deionized water for 4 to 5 times. The amount of water used for each wash is 2 to 3 times the mass of the filter cake. The filtrate after washing is tested. When the sulfate ion concentration in the filtrate is lower than 0.1 mol / L, it is considered qualified.

[0087] Beating: Beat the washed filter cake, and add sodium polyacrylate as a dispersant during the beating process. The beating is carried out using a high-speed disperser with a speed of 1500r / min and a beating time of 20min.

[0088] S7, drying and granulating the concentrated slurry obtained in step S6 to obtain the target product silica particles;

[0089] Drying: The concentrated slurry obtained in step S6 is sent to a spray dryer for drying using hot air generated by a natural gas burner. The inlet air temperature of the spray dryer is controlled at 300°C and the outlet air temperature is controlled at 120°C.

[0090] Granulation: The dried powdered product is put into a granulator for granulation, and a disc granulator is used for granulation. During the granulation process, sodium carboxymethyl cellulose is added as a binder. After the granulation is completed, the particles are sieved using a sieve and the particle size is selected within the range of 2 mm to obtain the target product, silica particles.

[0091] Table 1 is a comparison of the silicon dioxide particles in Examples 1 to 3.

[0092]

[0093]

[0094] From the above examples, it can be seen that, under the same conditions, the precipitated silica for low-wear conveyor belts of the present invention improves the mechanical properties of the rubber compound product and significantly improves the wear resistance by adding disodium lauryl sulfosuccinate as a dispersant.

[0095] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing precipitated silica for low-wear conveyor belts, characterized in that: The following steps are involved: S1. Select solid sodium silicate with a modulus of 3.0-3.3 and prepare a water glass solution with a concentration of 15wt% to 25wt% for standby use; The sulfuric acid solution is selected to have a concentration of 98 wt% for standby use; During the reaction, disodium lauryl sulfosuccinate was added as a reaction dispersant in an amount of 0.5% of the mass of silica; S2. Add 1 / 6 of the volume of industrial water as bottom water to the reactor, add the prepared water glass solution, accurately control the amount of the water glass solution added by a metering pump, add the water glass solution to the reactor in a dropwise manner, and add sodium sulfate as a reaction electrolyte. Set the reaction temperature to 70°C to 80°C and the stirring rate to 80 / min to 100 r / min; S3. At the set temperature and stirring rate, sodium silicate solution and sulfuric acid solution are added simultaneously, and the reaction pH is controlled in the range of 9.0 to 10.0 until the volume of the reaction system reaches 40% of the reactor, and the reaction time is 60 min; S4, maintaining the stirring rate unchanged, raising the reaction temperature to 80°C to 100°C, continuing to add the sodium silicate solution and the sulfuric acid solution, and maintaining the pH value of the reaction system in the range of 9.0 to 10.0 until the volume of the reaction system reaches 70% of the reactor, and the reaction time is 60 min; S5. Continue to add sulfuric acid solution, adjust the pH value of the reaction system to 5.0, stop adding acid, and continue aging the reaction system for 30 minutes. Keep stirring during the aging process at a stirring rate of 50 r / min to 60 r / min. The reaction is completed; S6, preparing a concentrated slurry by filtering, washing, and beating the reaction slurry obtained in step S5; Filtration: The reaction slurry obtained in step S5 is transported to a filter press through a pipeline for filtration; Washing: Wash the filter cake after filtration using deionized water for 4 to 5 times; Beating: Beat the washed filter cake and add sodium polyacrylate as a dispersant during the beating process; S7, drying and granulating the concentrated slurry obtained in step S6 to obtain the target product silica particles; Drying: The concentrated slurry obtained in step S6 is sent to a spray dryer for drying using hot air generated by a natural gas burner; Granulation: The dried powdered product is put into a granulator for granulation, and a disc granulator is used for granulation. During the granulation process, sodium carboxymethyl cellulose is added as a binder. After the granulation is completed, the particles are sieved using a sieve to obtain the target product, silica particles.

2. The method for preparing precipitated silica for low-wear conveyor belts according to claim 1, characterized in that: In step S1, when selecting solid sodium silicate, a 20-60 mesh screen is used to screen solid sodium silicate with uniform particle size; Preparation of water glass solution: slowly add the screened solid sodium silicate into industrial water. During the addition process, the stirring speed is 200r / min~300r / min, and the temperature is controlled at 20℃~30℃; Sulfuric acid solution: Before use, the sulfuric acid solution needs to be preheated through a heat exchanger and the preheating temperature should be set at 40℃~50℃; Reaction dispersant: Disodium lauryl sulfosuccinate is dissolved in deionized water before use to prepare a 10wt% to 15wt% solution. During the dissolution process, a magnetic stirrer is used to stir at a speed of 300r / min to 500r / min for 10min to 15min to ensure that the dispersant is completely dissolved.

3. The method for preparing precipitated silica for low-wear conveyor belts according to claim 1, characterized in that: In step S2, before using industrial water as bottom water, the reactor is first cleaned and dried, heated using a jacketed heating device, and stirred using an anchor stirrer; When adding the prepared water glass solution, the drop rate is controlled at 1mL / s to 2mL / s; Sodium sulfate is added as a reaction electrolyte. The amount of sodium sulfate added is accurately calculated based on the volume of the reactor and the requirements of the reaction system, and is generally 1 to 1.5 times the amount of silicon dioxide in the water glass solution.

4. The method for preparing precipitated silica for low-wear conveyor belts according to claim 1, characterized in that: In step S3, the sodium silicate solution and the sulfuric acid solution are added to the reactor by a multi-point nozzle method so that the solutions can be fully mixed and reacted in the reactor. The pH meter should be calibrated regularly, with a calibration period of every 20 minutes to 30 minutes.

5. The method for preparing precipitated silica for low-wear conveyor belts according to claim 1, characterized in that: In step S4, the temperature is gradually increased from 80°C to 90°C and then to 100°C, with the heating rate being controlled at 12°C / min to 2°C / min. Data collection was performed every 1 to 2 minutes and recorded.

6. The method for preparing precipitated silica for low-wear conveyor belts according to claim 1, characterized in that: In step S6, the amount of water used for each washing is 2 to 3 times the mass of the filter cake, and the filtrate after washing is tested. When the sulfate ion concentration in the filtrate is lower than 0.1 mol / L, the washing is considered qualified; The pressure of the filter press is controlled at 0.3MPa to 0.5MPa, and the beating is performed using a high-speed disperser with a rotation speed of 1000r / min to 1500r / min, and the beating time is 15min to 20min.

7. The method for preparing precipitated silica for low-wear conveyor belts according to claim 1, characterized in that: In step S7, the air inlet temperature of the spray dryer is controlled at 200°C to 300°C, and the air outlet temperature is controlled at 100°C to 120°C; The particle size is selected within the range of 0.5mm to 2mm.

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