A device and method for wet slurry hot balling of ceramic balls

Abstract

The present application relates to a kind of ceramic ball wet slurry hot balling device and method, thermometer device includes heat generator, closed ball rolling machine, dust collector, slurry tank, control system, exhaust system and near-infrared moisture meter;Method includes: raw material grinding stage adds grinding aid, plasticizer and defoaming agent to prepare slurry;Through control system preset parameter, after mother ball is rotted in closed ball rolling machine, hot air is passed in and slurry is sprayed, can dynamically adjust water wet balance, so that slurry is directly formed into ceramic ball.The present application simplifies "raw material grinding-drying-aging-molding" process, realizes one-step balling, reduces energy consumption, reduces water resource consumption, green body strength is high and has no layering defect, applicable to efficient batch production.

Description

Technical Field

[0001] This invention belongs to the field of ceramic ball forming equipment and technology, and particularly relates to a device and method for hot-drying ceramic ball wet slurry into balls. Background Technology

[0002] Ceramic ball rolling molding is a process that uses rotating equipment to gradually form powder or clay into balls during the rolling process. This method only requires a rotating drum or ball forming machine and has the advantages of low production cost, simple equipment structure, and low maintenance cost. It is especially suitable for mass standardized production of ceramic balls with a particle size of 0.5 to 50 mm. Moreover, the process has wide adaptability and can be formed by dry powder spraying water mist adhesion or clay rolling, without the need for complex molds.

[0003] However, existing rolling forming methods still have significant drawbacks:

[0004] Firstly, the molding quality and stability are insufficient. This method heavily relies on the adhesive properties of binders (such as pectin, polyvinyl alcohol (PVA), and carboxymethyl cellulose (CMC). If the binder's performance is insufficient or its compatibility with the raw materials is poor, it can easily lead to weak powder adhesion, low green body strength, and difficulty in achieving high-pressure densification during rolling, resulting in a green body density that is generally lower than that of isostatically pressed products. Furthermore, prolonged rolling can introduce defects such as inconsistent internal and external shrinkage, interlayer delamination, and impact damage, leading to poor uniformity of the green body structure and a high breakage rate in high-impact scenarios such as cement grinding and fine mining grinding.

[0005] Secondly, it is highly sensitive to process control. Strict requirements are placed on moisture control during the molding process, which requires spraying water mist or adding binders. If the moisture distribution is uneven or the drying is too fast, it can easily cause shrinkage and cracking of the green body, affecting the stability of the process.

[0006] Third, it has high energy consumption and low resource utilization. The conventional process requires drying the raw materials to obtain powder, and then re-spraying water to form the powder during tumbling. This involves multiple steps, including "raw material grinding - drying - aging - tumbling and forming," which results in high drying energy consumption, the inability to recover and reuse evaporated water, and the need for additional water replenishment during forming, leading to water waste.

[0007] Therefore, there is an urgent need to develop a ceramic ball forming method that can simplify the process, reduce energy consumption, and improve the strength and process stability of the green body, so as to overcome the above-mentioned defects. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a device and method for hot-drying ceramic spheres from wet slurry.

[0009] This ceramic ball wet slurry hot drying ball forming device includes: a heat generator, a closed ball rolling machine, a dust collector, a slurry tank, a control system, an exhaust system, and a near-infrared moisture meter;

[0010] The heat generator is connected to the sealed ball rolling machine through a hot air pipe. The sealed ball rolling machine is also connected to the dust collector through a secondary hot air pipe. The slurry tank is connected to the sealed ball rolling machine through a slurry pipe. A slurry spraying system is also provided to match the slurry tank.

[0011] The slurry pipe is placed inside the secondary hot air pipe, and the secondary hot air pipe is covered by a cold air pipe. The air inlet of the cold air pipe is close to the beginning of the secondary hot air pipe, and the direction of the cold air pipe is the same as that of the secondary hot air pipe. The air outlet of the cold air pipe is connected to the heat generator.

[0012] The control system is electrically connected to the slurry spraying system, the exhaust system, the heat generator, and the near-infrared moisture meter;

[0013] The slurry spraying system is used to determine the solid content of the slurry in the slurry tank according to the slurry solid content determination command of the control system, and to spray the slurry in the slurry tank according to the spraying command of the control system.

[0014] The exhaust system is used to discharge the secondary hot air from the sealed ball mill at a set air volume into the secondary hot air duct according to the secondary hot air discharge command of the control system.

[0015] A heat generator is used to supply a set volume of hot air into the hot air duct according to the hot air delivery command of the control system.

[0016] Near-infrared moisture meter is used to monitor the moisture content of the mother ball and its surface coating layer in the closed ball rolling machine in real time according to the moisture content measurement command of the control system. The feedback is fed back to the control system to adjust the hot air temperature T1 or the exhaust volume V2. The feedback control has a certain lag, but the feedback correction is very helpful to stabilize the water and moisture balance in the ball rolling machine.

[0017] The control system is used to send slurry solid content measurement instructions to the slurry spraying system, to send slurry spraying instructions to the slurry spraying system, to send hot air conveying instructions to the heat generator, to send moisture content measurement instructions to the near-infrared moisture meter, to calculate the target evaporation rate based on the preset slurry spraying flow rate, to calculate the initial hot air discharge volume based on the target evaporation rate, to send secondary hot air discharge instructions to the exhaust system, and to control the water and moisture balance inside the sealed ball mill.

[0018] As a preferred option:

[0019] A pressure gauge, hygrometer, and thermometer are installed at the end of the hot air duct closest to the closed ball rolling machine; a pressure gauge, hygrometer, and thermometer are also installed at the end of the secondary hot air duct closest to the closed ball rolling machine. The pressure gauge, hygrometer, and thermometer on the hot air duct are used to monitor the pressure, humidity, and temperature of the hot air entering the closed ball rolling machine, and the pressure gauge, hygrometer, and thermometer on the secondary hot air duct are used to monitor the pressure, humidity, and temperature of the secondary hot air exiting the closed ball rolling machine. The pressure gauge, hygrometer, and thermometer on the hot air duct and the pressure gauge, hygrometer, and thermometer on the secondary hot air duct are all electrically connected to the control system.

[0020] The exhaust system includes a variable frequency fan and an electric damper;

[0021] The slurry spraying system includes a variable frequency water pump.

[0022] As a preferred option: the shape of the closed ball rolling machine is an olive shape with vertical cuts at both ends, and it is placed horizontally, which is conducive to the uniform rotation of the ball blank in the ball rolling machine; the surface of the closed ball rolling machine is covered with heat insulation cotton to prevent heat loss; the hot air pipe, the secondary hot air pipe and the slurry pipe are all connected to the inside of the closed ball rolling machine from the center of the vertical cuts at both ends, without hindering the operation of the closed ball rolling machine.

[0023] This method for forming ceramic balls from wet slurry using the aforementioned apparatus includes the following steps:

[0024] Step 1, Raw Material Grinding: In the raw material grinding stage, grinding aids, plasticizers, and defoamers are added sequentially to obtain a slurry with a set solid content. The grinding aids can be composed of polyoxyethylene (20) sorbitan monostearate (i.e., Tween 60), sodium hexametaphosphate, Rohm and Haas 9300 dispersant, sodium silicate (water glass), and other types of dispersants. The addition of grinding aids can improve grinding efficiency. The plasticizers can be composed of polyvinyl alcohol, carboxymethyl cellulose (CMC), reinforcing agent FG-ZM01, and glycerol (glycerol), or other binders. The introduction of plasticizers can improve the plasticity of ceramic spheres. The defoamers can be tributyl phosphate, water-based silicone defoamers, polyethers, or other types of defoamers. The introduction of defoamers can improve the plasticity of ceramic spheres. The strength of the ceramic spheroid is enhanced to prevent cracking; grinding aids can effectively reduce the viscosity of the slurry, increase the solid content of the slurry, and also assist in grinding; plasticizers can effectively reduce defects such as interlayer peeling, impact damage, and unevenness between the inner and outer layers of the ceramic spheroid, and improve the strength of the ceramic spheroid, especially under high temperature (100-300℃) and low moisture content (5-15%) conditions, it has good spheroid strength; defoamers can effectively eliminate air bubbles in the slurry, increase the volume concentration of the slurry, and facilitate the realization of the wet slurry hot drying spheroidization method;

[0025] Step 2: Heat-dry the wet ceramic slurry to form balls:

[0026] Initialization: The target moisture content and spray flow rate are preset in the control system. The control system controls the slurry spraying system to measure the solid content of the slurry in the slurry tank. The near-infrared moisture meter monitors the moisture content of the mother ball and its surface coating layer in the closed ball rolling machine in real time according to the moisture content measurement command of the control system.

[0027] If the solid content of the slurry meets the standard, then:

[0028] Add a mother ball into a closed ball rolling machine to corrode the mother ball;

[0029] Parameter calculation: The control system calculates the target evaporation rate based on the preset spray flow rate, and calculates the temperature and initial air volume of the hot air introduced into the hot air duct by the heat generator based on the target evaporation rate.

[0030] Hot air is introduced: The heat generator produces hot air at the corresponding temperature and initial air volume, and the hot air enters the sealed ball rolling machine through the hot air pipe;

[0031] The enclosed ball rolling machine causes the corroded mother ball to roll. The slurry spraying system sprays slurry from the slurry tank onto the corroded mother ball inside the enclosed ball rolling machine at a set flow rate (the initial spray flow rate of the slurry is set according to the production capacity). The rolling action of the mother ball ensures that the slurry is evenly coated onto the corroded mother ball. Hot air from the hot air duct dries the slurry coated on the mother ball. The mother ball blank absorbs the moisture from the slurry, and the slurry is gradually dried and solidified (the blank gradually grows). The hot air becomes secondary hot air and enters the secondary hot air duct. The secondary hot air duct heats the slurry in its inner slurry pipe (reducing the energy consumption of hot air evaporation). The secondary hot air duct also heats the cold air in its outer cold air duct. The cold air in the cold air duct, heated by the secondary hot air, returns to the heat generator, which can reduce the energy consumption of the heat generator in heating the air. The secondary hot air after passing through the secondary hot air duct enters the dust collector. The secondary hot air that has been dusted by the dust collector is recycled back to the heat generator through the air duct.

[0032] During the growth and forming of the sphere blank, hot air and slurry are continuously introduced and secondary hot air is discharged. The control system controls the water and moisture balance in the closed ball rolling machine; it keeps the moisture content of the mother ball blank and the slurry layer on the surface stable (so that the moisture content of the ball blank is stable). As the slurry is sprayed, the slurry layer on the surface of the mother ball blank gradually increases and thickens, realizing the growth of the mother ball blank, and finally obtaining the dried ceramic ball.

[0033] If the solid content of the slurry does not meet the standard (i.e., the slurry concentration fluctuates), then:

[0034] Return to step one and adjust the ratio of raw materials, grinding aids, plasticizers, and defoamers to obtain a slurry with the required solid content.

[0035] The above-mentioned method of hot drying ceramic balls with wet slurry involves applying the raw material to the ball blank in the form of slurry, and then drying the excess moisture with hot air. This process can greatly reduce dust pollution. The secondary hot air is discharged through a design that wraps a cold air pipe around the secondary hot air pipe. By utilizing the principle of heat transfer, 20-30% of the heat can be recovered, reducing the heating energy consumption of the hot air generator.

[0036] The above-mentioned method for forming ceramic balls by hot baking wet slurry has the rolling and kneading characteristics of rolling and forming, and also combines the drying and bonding characteristics of slurry. This reduces the problem of layering and core encapsulation of the sphere blank, greatly improves the strength of the finished ceramic balls, reduces the strength dispersion of the finished ceramic balls, and reduces the risk of broken balls when used.

[0037] As a preferred option, in step one, during the raw material grinding stage:

[0038] The grinding aid is composed of polyoxyethylene (20) sorbitan monostearate (i.e., Tween 60), sodium hexametaphosphate, and sodium silicate (water glass) in a ratio of (1-3):(1-3):(1-5). The 20 in polyoxyethylene (20) sorbitan monostearate represents the number of ethylene oxide units. The total amount of the grinding aid is 0.05% to 0.8% of the total weight of the raw materials. The preferred ratio of Tween 60, sodium hexametaphosphate, and water glass is 1:2:4, which can effectively reduce the viscosity of the slurry, increase the solid content of the slurry, and at the same time play a role in grinding.

[0039] The plasticizer is composed of polyvinyl alcohol, reinforcing agent FG-ZM01 and glycerol (glycerol) in a ratio of (1-4):(1-2):(3-5). The total amount of plasticizer is 0.2% to 2% of the total weight of raw materials. The preferred ratio is polyvinyl alcohol, reinforcing plasticizer FG-ZM01 and glycerol in a ratio of 3:1:4, which can effectively improve the strength of the green body, especially under high temperature (temperature 100-300℃) and low moisture content (moisture content 5-15%) conditions, it has good green body strength and can prevent cracking caused by local high moisture content in the green body.

[0040] The defoamer is composed of tributyl phosphate and polyether in a ratio of (1:5) to (1:1). The total amount of defoamer is 0.1% to 0.5% of the total weight of the raw materials. It can effectively eliminate air bubbles in the slurry, increase the volume concentration of the slurry, and obtain the molding slurry required for hot drying of wet slurry into balls.

[0041] As a preferred option, in step one: a grinding aid is added at the beginning of the raw material grinding stage, and a plasticizer is added at the end of the raw material grinding stage. After adding the plasticizer, grinding continues for 5 to 10 minutes to ensure that the plasticizer is evenly ground. Then, a defoamer is added, and the slurry is obtained after the slurry is defoamed.

[0042] As a preferred option, in step two:

[0043] The specific method for corroding the mother ball is as follows: the slurry spraying system sprays the slurry from the slurry tank onto the mother ball and rotates the closed ball rolling machine to wet the surface of the mother ball. The machine is stopped for 10 to 60 minutes, allowing the water in the slurry to penetrate into the mother ball. The above action is repeated 2 to 5 times until the moisture content of the mother ball reaches 5 to 15% (i.e., the water has fully penetrated the mother ball), with a deviation of no more than 10%.

[0044] The temperature of the hot air supplied by the heat generator into the hot air duct is 100-300 ℃, and the temperature of the hot air varies depending on the material of the hot air duct.

[0045] In step two, when the slurry spraying system sprays the slurry from the slurry tank onto the mother ball after it has been corroded inside the closed ball rolling machine, the spraying rate is 0.5% to 2% of the total weight of the mother ball blank per minute.

[0046] Preferably, in step two, the control system controls the moisture balance within the sealed ball rolling machine as follows: The system observes the mother ball blanks after ball forming and adjusts the hot air temperature, secondary hot air volume, or slurry spraying volume in the hot air duct (adjusting the slurry delivery rate, hot air delivery rate, and secondary hot air outlet rate so that the moisture removed per minute by the secondary hot air duct equals the water content of the slurry sprayed per minute into the ball blank minus the water content when the slurry is converted into a ball blank; at this point, the ball blank moisture content reaches a stable state). The control system monitors the moisture content of the mother ball and its surface coating layer in real time using a near-infrared moisture meter. Based on the temperature and humidity measured by the thermometer and hygrometer, and the actual moisture removal volume calculated based on the secondary hot air volume, the control system adjusts the heat generator, exhaust system, and slurry spraying system, thereby controlling the hot air temperature and hot air delivery volume in the hot air duct, the slurry spraying volume onto the formed mother ball, and the secondary hot air volume in the secondary hot air duct. Let: the water removed per minute by the hot air = The water content of the slurry injected per minute - the water content of the slurry when it is transformed into the coating layer on the surface of the mother sphere; the control system performs sampling and calibration every 5 to 10 minutes.

[0047] When the surface of the mother ball blank after patching turns white or cracks, the control system reduces the temperature of the hot air in the hot air duct through the heat generator to check if there is local over-drying. When the mother ball blank sticks together after patching, there may be insufficient dehumidification. The control system increases the volume of secondary hot air in the secondary hot air duct through the exhaust system, or the control system adjusts the amount of slurry sprayed onto the patched mother ball by regulating the slurry spraying system.

[0048] When the control system detects an increase in the moisture content of the mother ball and its surface coating in the closed ball rolling machine based on the near-infrared moisture meter, the control system increases the secondary hot air volume in the secondary hot air duct through the exhaust system, or the control system increases the hot air temperature in the hot air duct through the heat generator.

[0049] When the control system detects a decrease in the moisture content of the mother ball and its surface coating in the closed ball rolling machine based on the near-infrared moisture meter, the control system reduces the secondary hot air volume in the secondary hot air duct through the exhaust system, or the control system reduces the hot air temperature in the hot air duct through the heat generator.

[0050] When the control system continuously monitors the moisture content of the mother ball and its surface coating layer in the closed ball rolling machine within the set range for 2 to 3 consecutive times using a near-infrared moisture meter, the closed ball rolling machine achieves a moisture balance.

[0051] Preferably, in step two, the control system calculates the required evaporation rate (M1) in real time based on the current spraying volume M2 and the slurry moisture content W1, thereby setting the initial values ​​of the hot air temperature T1 and the air supply volume V1 (by referring to a table or empirical formula). This control method is called feedforward control, and its advantage is that it responds quickly to changes in spraying volume and avoids lag. After achieving water and moisture balance in the closed ball mill, the following conditions are met:

[0052] M1 = M2 * (W1 - W2)

[0053] In the above formula, M1 is the mass of water removed by the hot air per minute, M2 is the mass of slurry injected per minute, W1 is the moisture content of the slurry, and W2 is the moisture content of the mother ball and its surface coating layer.

[0054] As a preferred option, in step two: when the solid content of the slurry in the slurry tank is within 35% to 65%, the solid content of the slurry meets the standard.

[0055] The beneficial effects of this invention are:

[0056] This invention simplifies the traditional ceramic ball rolling process into a single process of "raw material grinding - ceramic ball wet slurry hot drying into balls", eliminating the raw material drying and aging process. It directly uses the slurry to achieve molding in a closed ball rolling machine by controlling the hot air, thus solving the defects of high energy consumption, water waste and insufficient body strength in the background technology.

[0057] The control system of this invention adopts a combination of feedforward control and feedback control to achieve moisture balance control, with a high degree of automation and closed-loop control; it enables slurry with a moisture content of 50% to 75% to be directly evaporated into a green body with a moisture content of 5% to 15% without the need for additional water replenishment.

[0058] This invention involves adding grinding aids, plasticizers, and defoamers sequentially during the raw material grinding stage. The added grinding aids reduce slurry viscosity, improve grinding efficiency, and enhance slurry fluidity. The added plasticizers improve the plasticity and high-temperature strength of the green body, preventing cracking. The added defoamers eliminate air bubbles, increase slurry volume concentration, and avoid hollow defects in the finished product. The resulting ceramic ball green bodies have high density, uniform structure, no core delamination issues, and strong impact resistance, making them suitable for high-precision applications (such as mining grinding) with a significantly reduced breakage rate.

[0059] Compared to conventional processes, the method of this invention can reduce total energy consumption by 17%, reduce water consumption by 8%, and significantly improve the strength of the billet. It can effectively avoid the problem of core delamination and has the advantages of high efficiency, energy saving and stability. Attached Figure Description

[0060] Figure 1 A schematic diagram of a device for hot-drying ceramic spheres from wet slurry.

[0061] Figure 2 This is a schematic diagram of the vertical cross-sectional structure of the air inlet end of the cold air duct.

[0062] Figure 3 Circuit diagram of a device for hot-drying ceramic spheres from wet slurry.

[0063] Figure 4 The graph shows the test results of the crushing strength test of the pellets corresponding to the slurry obtained in Example 2 after adding different proportions of plasticizer to a 92 alumina ceramic slurry with grinding aid, grinding to a fineness of D50=0.8~1.0 micrometers and a solid content of 60%, and then grinding again.

[0064] Explanation of reference numerals in the attached diagram: 1. Heat generator; 2. Hot air duct; 3. Sealed ball rolling machine; 4. Secondary hot air duct; 5. Dust collector; 6. Slurry tank; 7. Slurry pipe; 8. Cold air duct; 9. Pressure gauge; 10. Hygrometer; 11. Thermometer. Detailed Implementation

[0065] The present invention will be further described below with reference to embodiments. The description of the embodiments below is only for the purpose of helping to understand the present invention. It should be noted that those skilled in the art can make several modifications to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0066] Example 1

[0067] A device for hot-drying ceramic slurry into spheres, such as... Figures 1 to 3As shown, it includes: a heat generator 1, a closed ball rolling machine 3, a dust collector 5, a slurry tank 6, a control system, an exhaust system, and a near-infrared moisture meter; the closed ball rolling machine 3 is shaped like an olive with vertical cuts at both ends, and the surface of the closed ball rolling machine 3 is covered with heat insulation cotton.

[0068] A heat generator 1 is connected to the interior of a sealed ball-rolling machine 3 via a hot air duct 2. The sealed ball-rolling machine 3 is also connected to a dust collector 5 via a secondary hot air duct 4. A slurry tank 6 is connected to the interior of the sealed ball-rolling machine 3 via a slurry pipe 7. A slurry spraying system is also provided to complement the slurry tank 6 (the hot air duct 2, secondary hot air duct 4, and slurry pipe 7 all connect to the interior of the sealed ball-rolling machine 3 from the center of the vertical cross-section at both ends, without hindering the operation of the sealed ball-rolling machine). A pressure gauge 9, a hygrometer 10, and a thermometer 11 are installed at the end of the hot air duct 2 closest to the sealed ball-rolling machine 3; the secondary hot air duct... 4. A pressure gauge 9, a hygrometer 10, and a thermometer 11 are also provided at one end near the sealed ball rolling machine 3. The pressure gauge, hygrometer, and thermometer on the hot air duct 2 are used to monitor the pressure, humidity, and temperature of the hot air entering the sealed ball rolling machine 3 and feed them back to the control system. The pressure gauge, hygrometer, and thermometer on the secondary hot air duct 4 are used to monitor the pressure, humidity, and temperature of the secondary hot air coming out of the sealed ball rolling machine 3 and feed them back to the control system. The pressure gauge, hygrometer, and thermometer on the hot air duct 2 and the pressure gauge, hygrometer, and thermometer on the secondary hot air duct 4 are all electrically connected to the control system.

[0069] Hot air duct 2 needs to be adapted to hot air environments of 100-300℃, and is made of 20G (boiler steel), 15CrMoG or 12Cr1MoV material (15CrMoG steel pipe is preferred); secondary hot air duct 4 needs to be adapted to high temperature and high humidity environments of 60-100℃ and has good heat exchange performance, and is made of 09CrCuSb (ND steel), 304 stainless steel or (S32205) duplex stainless steel material (304 stainless steel is preferred).

[0070] The slurry pipe 7 enters and is placed inside the secondary hot air pipe 4 (the secondary hot air can be used to heat the slurry). The secondary hot air pipe 4 is covered by a cold air pipe 8. The air inlet of the cold air pipe 8 is close to the beginning of the secondary hot air pipe 4. The direction of the cold air pipe 8 is the same as that of the secondary hot air pipe 4. The air outlet of the cold air pipe 8 is connected to the heat generator 1 (the heat of the secondary hot air can be used to heat the cold air, reducing the energy consumption of the heat generator 1 in heating the cold air).

[0071] The control system is electrically connected to the slurry spraying system, the exhaust system, the heat generator 1, and the near-infrared moisture meter;

[0072] The slurry spraying system is used to measure the solid content of the slurry in the slurry tank 6 according to the slurry solid content measurement command of the control system, and to spray the slurry in the slurry tank 6 according to the spraying command of the control system.

[0073] The exhaust system is used to discharge the secondary hot air from the sealed ball machine at a set air volume into the secondary hot air duct 4 according to the secondary hot air discharge command of the control system.

[0074] Heat generator 1 is used to introduce a set amount of hot air into hot air pipe 2 according to the hot air delivery command of the control system.

[0075] Near-infrared moisture meter is used to monitor the moisture content of the mother ball and its surface coating layer inside the closed ball rolling machine 3 in real time according to the moisture content measurement instructions of the control system.

[0076] The control system is used to send slurry solid content measurement instructions to the slurry spraying system, to send slurry spraying instructions to the slurry spraying system, to send hot air conveying instructions to the heat generator 1, to send moisture content measurement instructions to the near-infrared moisture meter, to calculate the target evaporation rate based on the preset slurry spraying flow rate, to calculate the initial hot air discharge flow rate based on the target evaporation rate, to send secondary hot air discharge instructions to the exhaust system, and to control the water and moisture balance inside the sealed ball mill 3.

[0077] Example 2

[0078] A method for forming ceramic spheres by hot baking of wet slurry includes the following steps:

[0079] Step 1: Raw material grinding: Add grinding aid at the beginning of the raw material grinding stage, add plasticizer at the end of the raw material grinding stage, continue grinding for 5-10 minutes after adding plasticizer to make the plasticizer evenly ground, add defoamer, and obtain slurry after the slurry is defoamed;

[0080] Different proportions of grinding aids (Tween 60, sodium hexametaphosphate, Rohm and Haas 9300 dispersant, and water glass) were added to alumina ceramic slurry with an initial fineness of D50 = 5 micrometers and a solid content of 60%. The total amount of aids was 0.08% of the slurry weight. Grinding was carried out until the final fineness was D50 = 0.8 micrometers. The grinding time for different groups was recorded, and the final slurry viscosity was tested using an NDJ-5S digital rotational viscometer. The viscosity results of the slurries obtained from different grinding groups are shown in Table 1 below.

[0081] Table 1. Viscosity data of slurries obtained after grinding with different proportions of grinding aids on alumina ceramic slurry with an initial fineness of D50=5 micrometers and a solid content of 60%.

[0082] As can be seen from Table 1 above, group A-2 (Tween 60: Sodium hexametaphosphate: Water glass = 1:2:4) performed best: compared with group A-4, the viscosity of group A-2 decreased by 54% and the grinding efficiency increased by 36%; while group A-4 had too high a proportion of water glass, resulting in a system pH > 10.5, which caused aluminum dissolution, and sodium hexametaphosphate was insufficient to weaken electrostatic repulsion; in summary, polyoxyethylene (20) sorbitan monostearate (i.e., Tween 60) in the grinding aid can reduce interfacial tension and promote wetting; sodium hexametaphosphate can chelate It also enhances the zeta potential; Tween 60 and sodium hexametaphosphate can synergistically adsorb onto the particle surface of alumina ceramic slurry; sodium silicate (water glass) can provide steric hindrance; Tween 60, sodium hexametaphosphate and sodium silicate can form a composite stabilizing mechanism, which helps to reduce slurry viscosity and improve grinding efficiency;

[0083] Different proportions of plasticizers (polyvinyl alcohol, carboxymethyl cellulose (CMC), glycerol, and reinforcing plasticizer FG-ZM01) were added to alumina ceramic slurry containing grinding aid (Tween 60: sodium hexametaphosphate: water glass = 1:2:4), ground to a fineness of D50 = 0.8–1.0 micrometers and a solid content of 60%. The total amount of plasticizer was 2% of the slurry weight. Grinding continued until the final fineness was D50 = 0.8 micrometers. The slurry was dried at 80℃ to prepare powder, then rolled into pellets with a particle size of 10 mm. The pellets were heated to 50, 100, 200, and 300℃, with the moisture content of the pellets controlled at 10%. The crushing strength was then tested using a pellet press. The test results are shown in Table 2 below.

[0084] Table 2 shows the test results of the crushing strength of the pellets corresponding to the 92 alumina ceramic slurry after adding grinding aids, grinding to a fineness of D50 = 0.8-1.0 micrometers and a solid content of 60%, and then adding different proportions of plasticizers and continuing grinding.

[0085] According to Table 2 above and Figure 4It can be seen that group B-4 (polyvinyl alcohol: glycerol: FG-ZM01 = 3:1:4), with a particle size of 10 mm and a moisture content of 10%, still maintains a strength of over 300 N at high temperatures of 100–300℃, and its strength stability is better than other groups. Control group B-6 (polyvinyl alcohol and glycerol only), however, shows PVA softening and decomposition at ≥200℃, resulting in a sharp drop in strength. In summary, glycerol, as a humectant, can improve the plasticity of the green body and effectively delay the moisture evaporation gradient; FG-ZM01, mainly a copolymer of carboxylic acid and sulfonate organic polymers, combined with inorganic binders and rheology modifiers, is a highly efficient ceramic green body reinforcing agent with good bonding performance, plasticity, and high-temperature weather resistance; polyvinyl alcohol can form a continuous film network, which can improve plasticity and bonding strength; the synergistic effect of polyvinyl alcohol, glycerol, and FG-ZM01 can effectively improve the plasticity, moisture retention, and high-temperature weather resistance of the green body.

[0086] A grinding aid (Tween 60: sodium hexametaphosphate: water glass = 1:2:4) was added to an alumina ceramic slurry with an initial fineness of D50 = 5 micrometers and a solid content of 60% for initial grinding. A plasticizer (polyvinyl alcohol: glycerol: FG-ZM01 = 3:1:4) was added, and grinding continued for 5–10 minutes. Then, different proportions of defoamers (tributyl phosphate, water-based silicone defoamer, polyether defoamer) were added, with the total amount of defoamer being 0.1% of the slurry weight. Grinding continued until the final fineness was D50 = 0.8 micrometers. The bubble situation in the slurry was observed (see Table 3 below). The true density and apparent density were tested using the hydrostatic bottle method, and the bubble volume fraction and slurry volume concentration (C0) were calculated. v The calculation formula for ) is as follows:

[0087] C v =〔1-ρ true *(1-C w ) / ρ l 〕*(1-ε g )

[0088] In the above formula, ρ true ρ represents the actual density of the slurry, and ρ1 represents the density of the liquid water; C w ε represents the solid content of the slurry by mass, and ε represents the volume fraction of air bubbles.

[0089] Table 3 shows the surface condition of 92% alumina ceramic slurry with an initial fineness of D50 = 5 micrometers and a solid content of 60%, after initial grinding with grinding aid (Tween 60: sodium hexametaphosphate: water glass = 1:2:4), followed by grinding with plasticizer (polyvinyl alcohol: glycerol: FG-ZM01 = 3:1:4) for 5-10 minutes, and then adding different proportions of defoamer.

[0090] As shown in Table 3 above, group C-3 (tributyl phosphate: polyether defoamer = 1:5) has the best overall performance, the lowest bubble content (0.5%), and an increased volume concentration of 27.64%, which helps to improve the compactness of the spheres. In summary, tributyl phosphate can quickly break up large bubbles introduced by grinding, while polyether can effectively suppress bubbles for a long time and prevent re-foaming during subsequent stirring / transportation. Although water-based silicone defoamers have strong bubble-eliminating performance, they can cause uneven surface tension of particles, which can easily lead to shrinkage cavities and hollow spheres.

[0091] Step 2: Heat-dry the wet ceramic slurry to form balls:

[0092] Initialization: The target moisture content and spray flow rate are preset in the control system. The control system controls the slurry spraying system to measure the solid content of the slurry in the slurry tank 6. The near-infrared moisture meter monitors the moisture content of the mother ball and its surface coating layer in the sealed ball rolling machine 3 in real time according to the moisture content measurement command of the control system.

[0093] If the solid content of the slurry meets the standard, then:

[0094] Add mother balls to the closed ball rolling machine 3, turn on the closed ball rolling machine 3, and corrode the mother balls: the slurry spraying system sprays the slurry in the slurry tank 6 onto the mother balls through the slurry pipe 7 and rotates the closed ball rolling machine 3 to wet the surface of the mother balls. Stop the machine for 10 to 60 minutes to allow the water in the slurry to penetrate into the interior of the mother balls. Repeat the above actions 2 to 5 times until the moisture content of the mother balls reaches 5 to 15% (i.e., the water has fully penetrated the mother balls), with a deviation of no more than 10%.

[0095] Parameter calculation: The control system calculates the target evaporation rate based on the preset spray flow rate, and calculates the temperature and initial air volume of the hot air introduced into the hot air duct 2 by the heat generator 1 based on the target evaporation rate.

[0096] After the ball rolling is completed, turn on the heat generator 1 and introduce hot air: the heat generator 1 generates hot air at 100-300 ℃ and an initial air volume, and the hot air enters the sealed ball rolling machine 3 through the hot air pipe 2.

[0097] The sealed ball rolling machine 3 causes the corroded mother ball to roll. The slurry spraying system sprays the slurry from the slurry tank 6 through the slurry pipe 7 at a set flow rate onto the corroded mother ball inside the sealed ball rolling machine 3 (the spraying rate during slurry spraying is 0.5% to 2% of the total weight of the mother ball blank). The rolling action of the mother ball ensures that the slurry is evenly coated onto the corroded mother ball. The hot air delivered by the hot air pipe 2 dries the slurry coated on the mother ball. The mother ball blank absorbs the moisture in the slurry, and the slurry is gradually dried and solidified. The hot air then becomes high-humidity. Secondary hot air, high humidity secondary hot air enters secondary hot air duct 4; secondary hot air duct 4 heats the slurry in the slurry pipe 7 inside (reducing the energy consumption for heating and evaporating the slurry); secondary hot air duct 4 also heats the cold air in the external cold air duct 8; the cold air in the cold air duct 8, after being heated by secondary hot air, returns to the heat generator 1, which can reduce the energy consumption of the heat generator in heating the air; the secondary hot air after passing through secondary hot air duct 4 enters the dust collector 5; the secondary hot air after being dusted by the dust collector 5 is reused in the heat generator 1 through the air duct or discharged into the air;

[0098] Hot air and slurry are continuously introduced, and secondary hot air is discharged. The control system maintains the moisture balance within the sealed ball mill 3.

[0099] The mother ball blank after sizing is observed, and the hot air temperature, secondary hot air volume, or slurry spraying volume in hot air duct 2 is adjusted. The control system monitors the moisture content of the mother ball and its surface coating layer inside the sealed ball rolling machine 3 in real time using a near-infrared moisture meter. The control system calculates the actual moisture removal volume based on the temperature and humidity measured by thermometer 11 and hygrometer 10, and the secondary hot air volume, and adjusts the heat generator 1, the exhaust system, and the slurry spraying system. This, in turn, controls the hot air temperature and hot air volume in hot air duct 2, adjusts the slurry spraying volume onto the sizing mother ball, and adjusts the secondary hot air volume in secondary hot air duct 4. Let: the mass of moisture removed by hot air per minute = the mass of moisture in the slurry sprayed per minute - the mass of moisture in the slurry when it is converted into the surface coating layer of the mother ball. The control system performs sampling calibration every 5-10 minutes.

[0100] When the surface of the mother ball blank after patching turns white or cracks, the control system reduces the temperature of the hot air in the hot air pipe 2 through the heat generator 1 to check if there is local over-drying. When the mother ball blank sticks together after patching, there may be insufficient dehumidification. The control system increases the volume of secondary hot air in the secondary hot air pipe 4 through the exhaust system, or the control system adjusts the amount of slurry sprayed onto the patched mother ball by regulating the slurry spraying system.

[0101] When the control system detects an increase in the moisture content of the mother ball and its surface coating in the sealed ball rolling machine 3 based on the near-infrared moisture meter, the control system increases the secondary hot air volume in the secondary hot air duct 4 through the exhaust system, or the control system increases the hot air temperature in the hot air duct 2 through the heat generator 1.

[0102] When the control system detects a decrease in the moisture content of the mother ball and its surface coating in the closed ball rolling machine 3 based on the near-infrared moisture meter, the control system reduces the secondary hot air volume in the secondary hot air duct 4 through the exhaust system, or the control system reduces the hot air temperature in the hot air duct 2 through the heat generator 1.

[0103] When the control system continuously monitors the moisture content of the mother ball and its surface coating layer inside the closed ball rolling machine 3 within the set range for 2-3 consecutive times using a near-infrared moisture meter, a moisture balance is achieved inside the closed ball rolling machine 3; the moisture content of the mother ball blank and the slurry layer on its surface remains stable (ensuring stable moisture content of the ball blank); achieving moisture balance satisfies the following conditions:

[0104] M1 = M2 * (W1 - W2)

[0105] In the above formula, M1 is the mass of water removed by hot air per minute, M2 is the mass of slurry injected per minute, W1 is the moisture content of the slurry, and W2 is the moisture content of the mother ball and its surface coating layer; at this time, the moisture content of the ball blank reaches a stable state.

[0106] Hot air and slurry are continuously introduced to control the water and moisture balance inside the ball rolling machine, so that the moisture content of the ball blank inside the closed ball rolling machine is stable. As the slurry is sprayed, the slurry layer on the surface of the mother ball blank gradually increases and thickens, realizing the growth of the mother ball blank, and finally obtaining dried ceramic balls that reach the target particle size.

[0107] If the solid content of the slurry does not meet the standard (i.e., the slurry concentration fluctuates), then:

[0108] Return to step one and adjust the ratio of raw materials, grinding aids, plasticizers and defoamers to obtain a slurry with a solid content of 35-65% that meets the solid content standard.

[0109] Example 3

[0110] A method for forming 92 alumina ceramic balls from a wet slurry by hot drying includes the following steps: raw material grinding and ceramic ball forming.

[0111] Step 1: The initial powder fineness D50 = 5 micrometers, weighing 1 ton, is ground using a 150L vertical sand mill. The slurry solid content is controlled at 35%. Grinding aid (Tween 60: sodium hexametaphosphate: water glass = 1:2:4) is added at the initial stage of raw material grinding. The total amount of grinding aid is 0.05% of the slurry weight.

[0112] Step 2: In the later stage of raw material grinding, when the slurry fineness reaches the target D50 = 0.8 microns, add plasticizer (polyvinyl alcohol: glycerol: FG-ZM01 = 3:1:4) and continue grinding. The total amount of plasticizer used is 0.2% of the slurry weight.

[0113] Step 3: Following Step 2, continue grinding until the plasticizer is uniformly ground. Then, add defoamer (tributyl phosphate: polyether defoamer = 1:1), with the total amount of defoamer being 0.1% of the slurry weight. The final slurry is then formed, with a solid content controlled at 35%. The entire grinding process takes 5 hours and consumes 550 kWh / ton of energy.

[0114] Step 4: During the forming of ceramic balls, a closed hot air rolling device is used. First, a 0.5 mm mother ball is added for ball forming. The specific operation is as follows: add the mother ball into the closed rolling machine, spray the forming slurry, and rotate the closed rolling machine to wet the surface of the mother ball. Then stop the machine for 10 minutes to allow the water in the slurry to penetrate into the mother ball. Repeat the above action twice until the water fully wets the mother ball, at which point the water content of the mother ball is 15%. After the ball forming is completed, 200℃ hot air is introduced, and 80℃ secondary hot air is discharged. Then, the forming slurry obtained in Step 3 is sprayed onto the mother ball at a rate of approximately 0.5% of the total weight of the ball blank per minute. The slurry is evenly coated onto the ball blank by the rolling action of the ball blank. The ball blank has a water absorption capacity. At the same time, by adjusting the flow rate or temperature of the secondary hot air, the water removed by the hot air per minute is equal to the water content of the slurry sprayed per minute minus the water content of the slurry when it is converted into a ball blank.

[0115] M1 = M2 * (W1 - W2)

[0116] In the above formula, M1 is the mass of water removed by hot air per minute, M2 is the mass of slurry injected per minute, W1 is the moisture content of the slurry, and W2 is the moisture content of the mother ball and its surface coating layer.

[0117] The moisture content of the ball blanks in the closed ball rolling machine is set to 15%, with a deviation of no more than 10%. The moisture content is monitored in real time by an online near-infrared (NIR) moisture meter. If the moisture content is too high, the exhaust volume or exhaust temperature is increased, and vice versa. When the moisture content is within the target range for 2 to 3 consecutive tests, it is considered that the balance has been achieved.

[0118] During the spheroid growth and forming process, hot air and slurry are continuously introduced to control the moisture balance within the spheroidizing machine. The spheroid gradually grows larger, resulting in 92 alumina ceramic spheres with a particle size of 20 mm. The energy consumption for forming 1 ton of dry powder is 1823 WKh / T (W 滚球机 =200WKh / T, W 湿浆热烘 =1623WKh / T), the additional water consumption for forming 1 ton of dry powder into pellets is 0T / T. The evaporated water is 1.681T / T.

[0119] Example 4

[0120] A method for forming zirconia ceramic spheres with a particle size of 10 mm by hot drying of wet slurry includes raw material grinding and ceramic sphere forming steps, specifically:

[0121] Step 1: The initial powder fineness D50 = 2 microns, weighing 1 ton, is ground using a 150L vertical sand mill. The solid content of the slurry is controlled at 65%. A grinding aid composed of Tween 60, sodium hexametaphosphate, and water glass is added at the initial stage of raw material grinding. The total amount is 0.08% of the slurry weight, and the ratio is 1:2:4.

[0122] Step 2: In the later stage of raw material grinding, when the slurry fineness reaches the target D50=0.3 microns, add a plasticizer, which is composed of polyvinyl alcohol, reinforcing plasticizer FG-ZM01 and glycerin, with a total amount of 2% of the slurry weight; the ratio is 3:1:4.

[0123] Step 3: Following Step 2, continue grinding for 5-10 minutes to ensure the plasticizer is evenly ground. Then, add the defoamer, which is a combination of tributyl phosphate and polyether defoamer, with a total dosage of 0.5% of the slurry weight and a ratio of 1:5. The final slurry is then formed, with the solid content controlled at 65%. The entire grinding process takes 10 hours and consumes 1050 kWh / T of energy.

[0124] Step 4: During the forming of ceramic balls, a closed hot air rolling device is used. First, a 1 mm mother ball is added for ball forming. Specifically, the mother ball is added to the closed rolling machine, the forming slurry is sprayed, and the machine is rotated to wet the surface of the mother ball. Then, the machine is stopped for 60 minutes to allow the water in the slurry to penetrate into the mother ball. This process is repeated 5 times until the water fully wets the mother ball, at which point the mother ball has a moisture content of 5%. After ball forming, 300℃ hot air is introduced and 80℃ air is discharged. Then, the forming slurry obtained in Step 3 is sprayed onto the mother ball at a rate of approximately 2% of the total weight of the ball blank per minute. The rolling action of the ball blank ensures that the slurry is evenly coated onto the ball blank. The ball blank has a water absorption capacity. By adjusting the flow rate or temperature of the secondary hot air, the water removed by the hot air per minute is equal to the water content of the slurry sprayed per minute minus the water content of the slurry when it is converted into a ball blank. The calculation formula is as follows:

[0125] M1 = M2 * (W1 - W2)

[0126] In the above formula, M1 is the mass of water removed by hot air per minute, M2 is the mass of slurry injected per minute, W1 is the moisture content of the slurry, and W2 is the moisture content of the mother ball and its surface coating layer.

[0127] The moisture content of the spheres inside the closed ball rolling machine is set to 5%, with a deviation not exceeding 10%. The moisture content is monitored in real time by an online near-infrared (NIR) moisture meter. If the moisture content is too high, the exhaust air volume or temperature is increased; conversely, it is decreased if the moisture content is too low. When the moisture content is within the target range for 2-3 consecutive tests, it is considered to have reached equilibrium. Hot air and slurry are continuously introduced to control the moisture balance inside the ball rolling machine, and the spheres gradually grow larger, resulting in zirconia ceramic spheres with a particle size of 10 mm. The energy consumption for molding 1 ton of dry powder is 860 WHh / T (W). 滚球机 =210 kWh, W 湿浆热烘 =650kWh), the additional water consumed in forming 1 ton of dry powder into pellets is 0T / T. The evaporated water is 0.486T / T.

[0128] Comparative Example 1

[0129] A conventional method for preparing 92 alumina ceramic spheres with a particle size of 20 mm includes the following steps: raw material grinding, slurry drying, powder aging, and powder pelletizing. Specifically:

[0130] Step 1: Grinding raw materials. The initial powder fineness D50 = 5 microns, weight 1 ton, using a 150L vertical sand mill abrasive, without adding any grinding aids, the slurry solid content is controlled at 35%, the grinding time is 6.8h, the final slurry fineness D50 = 0.8 microns, and the energy consumption is 798KWh / T.

[0131] Step 2: Slurry drying. Spray drying is used to dry the slurry with a solid content of 35%. The inlet hot air temperature is 400℃ and the outlet exhaust air temperature is 150℃. The slurry is dried into powder with a moisture content of 1%. The amount of water evaporated to dry 1 ton of powder is 1.847T, and the energy consumption is 1850KWh / T.

[0132] Step 3: Powder aging. The powder produced by spray drying has a high temperature and uneven physicochemical properties, so it needs to be aged in a cool and humid environment for 5 to 20 days.

[0133] Step 4: During the forming process, a ball-disc rolling mill is used to form the ceramic balls using a rolling method. Mother balls are added to the rolling mill, followed by the simultaneous spraying of a forming slurry containing 1% polyvinyl alcohol and the addition of powder. The initial moisture content of the powder is 1%, and the moisture content of the spheres is controlled to remain stable at 15%. The spheres are rolled and grown to obtain 92 alumina ceramic balls with a particle size of 20 mm. The energy consumption for forming 1 ton of dry powder using the ball-disc rolling mill is 225 kWh / ton, and the additional water consumption for forming 1 ton of dry powder into balls is 0.166 tons / ton.

[0134] The technical solutions of Examples 3 and 4 are compared with those of Comparative Example 1. The comparison results are shown in Table 4 below:

[0135] Table 4. Overall Comparison of the Combined Schemes of Examples 3 and 4 with the Technical Solution of Comparative Example 1 From Table 4 above, it is clear that:

[0136] Using a combination of Examples 3 and 4, grinding aids, plasticizers, and defoamers were added during the grinding process. Compared with the conventional method in Comparative Example 1 without additives, the grinding time was shortened by 26%.

[0137] By using the combined scheme of Examples 3 and 4, it is only necessary to dry the slurry with a moisture content of 65% into a ball blank with a moisture content of 15%. Compared with the conventional scheme of Comparative Example 1, which directly evaporates the moisture of the slurry to a powder with a moisture content of 1%, the moisture evaporation during drying is reduced by 9%.

[0138] Using the combined scheme of Examples 3 and 4, only the slurry with a moisture content of 65% needs to be dried into a ball blank with a moisture content of 15%, without the need to add any other water during the process; compared with Comparative Example 1, which still requires the addition of 15% water during the ball blank forming process, the total water consumption in production is reduced by 8%;

[0139] By combining the solutions of Examples 3 and 4, additives are added during the grinding process to improve grinding efficiency, and a wet slurry hot drying molding method is used for molding. Compared with the conventional solution of "grinding without additives + spray drying + roll forming" in Comparative Example 1, the total production energy consumption is reduced by 17%.

[0140] In addition, Comparative Example 1 also involves problems such as long aging time, large site usage, complicated transfer, and dust pollution. The solutions of Example 3 and Example 4 basically do not have these problems and have great advantages.

[0141] It should be noted that those skilled in the art can make various modifications to this invention without departing from its principles, and these modifications and improvements also fall within the scope of protection of this application.

Claims

1. A device for hot-drying ceramic slurry into spheres, characterized in that, include: Heat generator, closed ball mill, dust collector, slurry tank, control system, exhaust system and near-infrared moisture meter; The heat generator is connected to the sealed ball rolling machine through a hot air pipe. The sealed ball rolling machine is also connected to the dust collector through a secondary hot air pipe. The slurry tank is connected to the sealed ball rolling machine through a slurry pipe. A slurry spraying system is also provided to match the slurry tank. The slurry pipe is placed inside the secondary hot air pipe, and the secondary hot air pipe is covered with a cold air pipe. The air inlet of the cold air pipe is close to the beginning of the secondary hot air pipe, and the air outlet of the cold air pipe is connected to the heat generator. The control system is electrically connected to the slurry spraying system, the exhaust system, the heat generator, and the near-infrared moisture meter; The slurry spraying system is used to measure the solid content of the slurry in the slurry tank according to the slurry solid content measurement command of the control system, and to spray the slurry in the slurry tank according to the spraying command of the control system. The exhaust system is used to discharge the secondary hot air from the sealed ball machine at a set air volume into the secondary hot air duct according to the secondary hot air discharge command of the control system. The heat generator is used to supply a set amount of hot air into the hot air duct according to the hot air delivery command of the control system. The near-infrared moisture meter is used to monitor the moisture content of the mother ball and its surface coating layer inside the closed ball rolling machine in real time according to the moisture content measurement command of the control system. The control system is used to send a slurry solid content measurement command to the slurry spraying system, a slurry spraying command to the slurry spraying system, a hot air conveying command to the heat generator, a moisture content measurement command to the near-infrared moisture meter, calculate the target evaporation rate based on the preset slurry spraying flow rate, calculate the initial hot air discharge flow rate based on the target evaporation rate, send a secondary hot air discharge command to the exhaust system, and control the water and moisture balance inside the sealed ball mill.

2. The ceramic ball wet slurry hot drying ball forming device according to claim 1, characterized in that: A pressure gauge, a hygrometer, and a thermometer are installed at the end of the hot air duct near the sealed ball rolling machine; a pressure gauge, a hygrometer, and a thermometer are also installed at the end of the secondary hot air duct near the sealed ball rolling machine; the pressure gauge, hygrometer, and thermometer on the hot air duct are used to monitor the pressure, humidity, and temperature of the hot air entering the sealed ball rolling machine, and the pressure gauge, hygrometer, and thermometer on the secondary hot air duct are used to monitor the pressure, humidity, and temperature of the secondary hot air exiting the sealed ball rolling machine; the pressure gauge, hygrometer, and thermometer on the hot air duct and the pressure gauge, hygrometer, and thermometer on the secondary hot air duct are all electrically connected to the control system; The exhaust system includes a variable frequency fan and an electric air valve; The slurry spraying system includes a variable frequency water pump.

3. The ceramic ball wet slurry hot drying ball forming device according to claim 2, characterized in that: The sealed ball rolling machine is shaped like an olive with vertical cuts at both ends, and its surface is covered with insulation cotton. The hot air pipe, the secondary hot air pipe, and the slurry pipe all enter the interior of the sealed ball rolling machine from the center of the vertical cuts at both ends.

4. A method for forming ceramic balls by hot drying of wet slurry using the apparatus described in claim 3, characterized in that, Includes the following steps: Step 1, Raw material grinding: Grinding aid, plasticizer and defoamer are added in sequence during the raw material grinding stage, and the slurry with the set solid content is obtained by grinding. Step 2: Heat-dry the wet ceramic slurry to form balls: Initialization: The target moisture content and spray flow rate are preset in the control system. The control system controls the slurry spraying system to measure the solid content of the slurry in the slurry tank. The near-infrared moisture meter monitors the moisture content of the mother ball and its surface coating layer in the closed ball rolling machine in real time according to the moisture content measurement command of the control system. If the solid content of the slurry meets the standard, then: A mother ball is added to the closed ball rolling machine, and the mother ball is subjected to ball corrosion. Parameter calculation: The control system calculates the target evaporation rate based on the preset spray flow rate, and calculates the temperature and initial air volume of the hot air introduced into the hot air duct by the heat generator based on the target evaporation rate; Hot air is introduced: The heat generator produces hot air at a corresponding temperature and initial air volume, and the hot air enters the sealed ball rolling machine through the hot air pipe; The sealed ball rolling machine causes the corroded mother ball to roll. The slurry spraying system sprays slurry from the slurry tank onto the corroded mother ball inside the sealed ball rolling machine at a set flow rate through the slurry pipe. The slurry evenly coats the corroded mother ball. Hot air from the hot air pipe dries the slurry coating the mother ball. The mother ball blank absorbs moisture from the slurry, and the slurry gradually dries and solidifies. The hot air becomes secondary hot air and enters the secondary hot air pipe. The secondary hot air pipe heats the slurry in its inner slurry pipe and also heats the cold air in its outer cold air pipe. The cold air in the cold air pipe, heated by the secondary hot air, returns to the heat generator. The secondary hot air after passing through the secondary hot air pipe enters the dust collector. The secondary hot air that has been cleaned by the dust collector is then recycled back to the heat generator through the air duct. Hot air and slurry are continuously introduced, and secondary hot air is discharged. The control system controls the water and moisture balance inside the closed ball rolling machine; it keeps the moisture content of the mother ball blank and the slurry layer on its surface stable. As the slurry is sprayed, the slurry layer on the surface of the mother ball blank gradually increases and thickens, and finally the dried ceramic ball is obtained. If the solid content of the slurry does not meet the standard, then: Return to step one and adjust the ratio of raw materials, grinding aids, plasticizers, and defoamers to obtain a slurry with the required solid content.

5. The method according to claim 4, characterized in that, In step one, during the raw material grinding stage: The grinding aid is composed of polyoxyethylene (20) sorbitan monostearate, sodium hexametaphosphate, and sodium silicate in a ratio of (1-3):(1-3):(1-5), where 20 in polyoxyethylene (20) sorbitan monostearate represents the number of ethylene oxide units, and the total amount of the grinding aid is 0.05% to 0.8% of the total weight of the raw materials. The plasticizer is composed of polyvinyl alcohol, reinforcing agent FG-ZM01, and glycerol in a ratio of (1-4):(1-2):(3-5), and the total amount of the plasticizer is 0.2% to 2% of the total weight of the raw materials. The defoamer is composed of tributyl phosphate and polyether in a ratio of (1:5) to (1:1), and the total amount of the defoamer is 0.1% to 0.5% of the total weight of the raw materials.

6. The method according to claim 5, characterized in that, In step one: the grinding aid is added at the beginning of the raw material grinding stage, the plasticizer is added at the end of the raw material grinding stage, the grinding continues for 5 to 10 minutes after the plasticizer is added, the defoamer is added, and the slurry is obtained after the slurry is defoamed.

7. The method according to claim 6, characterized in that, In step two: The specific method for corroding the mother ball is as follows: the slurry spraying system sprays the slurry from the slurry tank onto the mother ball and rotates the closed ball rolling machine to wet the surface of the mother ball. The machine is stopped for 10 to 60 minutes, and the water in the slurry penetrates into the interior of the mother ball. The above action is repeated 2 to 5 times until the moisture content of the mother ball reaches 5 to 15%. The temperature of the hot air supplied by the heat generator to the hot air duct is 100-300 °C; In step two, when the slurry spraying system sprays the slurry from the slurry tank onto the mother ball after it has been corroded inside the sealed ball rolling machine, the spraying rate per minute is 0.5% to 2% of the total weight of the mother ball blank.

8. The method according to claim 7, characterized in that, In step two, the control system controls the water and moisture balance within the sealed ball rolling machine by: observing the mother ball blank after ball rot and adjusting the hot air temperature, secondary hot air volume, or slurry spraying volume in the hot air duct; the control system monitors the moisture content of the mother ball and its surface coating layer in the sealed ball rolling machine in real time using a near-infrared moisture meter; the control system calculates the actual moisture removal volume based on the temperature and humidity measured by the thermometer and hygrometer, and the secondary hot air volume, and adjusts the heat generator, the exhaust system, and the slurry spraying system, thereby adjusting the hot air temperature and hot air supply volume in the hot air duct, adjusting the slurry spraying volume onto the mother ball after ball rot, and adjusting the secondary hot air volume in the secondary hot air duct; Let: The mass of water removed by hot air per minute = the mass of water content of the slurry injected per minute - the mass of water content of the slurry when it is transformed into the coating layer on the surface of the mother sphere; the control system performs sampling calibration every 5 to 10 minutes; When the surface of the mother ball blank after the ball is whitish or cracked, the control system reduces the temperature of the hot air in the hot air pipe through the heat generator to check whether there is local over-drying. When the mother ball blanks stick together after the mother ball is corroded, the control system increases the secondary hot air volume in the secondary hot air duct through the exhaust system, or the control system adjusts the amount of slurry sprayed onto the corroded mother ball by adjusting the slurry spraying system. When the control system detects an increase in the moisture content of the mother ball and its surface coating in the sealed ball rolling machine using a near-infrared moisture meter, the control system increases the secondary hot air volume in the secondary hot air duct through the exhaust system, or the control system increases the hot air temperature in the hot air duct through the heat generator. When the control system detects a decrease in the moisture content of the mother ball and its surface coating in the closed ball rolling machine based on the near-infrared moisture meter, the control system reduces the secondary hot air volume in the secondary hot air duct through the exhaust system, or the control system reduces the hot air temperature in the hot air duct through the heat generator. When the control system continuously monitors the moisture content of the mother ball and its surface coating layer in the closed ball rolling machine within the set range for 2 to 3 consecutive times according to the near-infrared moisture meter, the closed ball rolling machine achieves water and moisture balance.

9. The method according to claim 8, characterized in that, In step two, after the control system achieves water and moisture balance within the sealed ball rolling machine, the following conditions are met: M1 = M2 * (W1 - W2) In the above formula, M1 is the mass of water removed by the hot air per minute, M2 is the mass of slurry injected per minute, W1 is the moisture content of the slurry, and W2 is the moisture content of the mother ball and its surface coating layer.

10. The method according to claim 4, characterized in that, In step two: when the solid content of the slurry in the slurry tank is within 35% to 65%, the solid content of the slurry meets the standard.

Images