Continuous production method for atomizing and passivating lime particles based on silicone oil and passivating device

Abstract

The invention provides a continuous production method for atomizing and passivating lime particles based on silicone oil and a passivation device, and belongs to the technical field of inorganic material surface treatment. Lime particles are fluidized in a fluidized bed device, feeding stability is guaranteed through a weighing sensor and a PID controller, and waste gas is treated through a bag-type dust collector; the silicone oil is atomized according to the proportion; mixing the atomized silicone oil with the fluidized lime particles by using an ejector in the mixing pipe, optimizing the mixing effect through structures such as a central cone and the like, and controlling the gas temperature; the two are collided and combined in the mixing pipe to finish passivation; and finally collecting finished products. The device can realize efficient passivation of the surfaces of lime particles, improves the moisture resistance and fluidity of the lime particles, can realize continuous production, is energy-saving and environment-friendly, and is simple and convenient to operate; meanwhile, a sealing cover and an air exhaust pipeline are arranged at the feeding opening and connected into the bag-type dust collector, so that the problem that waste gas escapes in the feeding process is effectively solved.

Description

Technical Field

[0001] The invention belongs to the technical field of inorganic material surface treatment, and in particular relates to a continuous production method and a passivation device based on silicone oil atomization passivation of lime particles. Background Art

[0002] During storage and transportation, lime particles can easily absorb moisture from the air and agglomerate, seriously affecting their subsequent performance. For example, in building material applications, agglomerated lime can reduce the bonding strength of mortar and affect construction quality; in chemical production, agglomerated lime can interfere with the reaction process and reduce product quality and production efficiency.

[0003] At present, the traditional lime passivation method is mainly physical mixing or coating process. In the physical mixing process, the silicone oil and lime particles are difficult to be fully and evenly dispersed, resulting in uneven passivation effects. The amount of silicone oil attached to the surface of some lime particles is insufficient, and the moisture-proof effect cannot be effectively played. Although the coating process can improve the passivation uniformity to a certain extent, it has the problem of low efficiency, requires a lot of time and manpower for coating operations, and has high energy consumption in heating and drying, which does not conform to the development trend of energy conservation and environmental protection in modern industry.

[0004] At the same time, the prior art lacks a lime passivation method and passivation device that can achieve continuous production, which is difficult to meet the needs of large-scale industrial production. Therefore, the development of a continuous, efficient and environmentally friendly lime passivation technology is of great significance to promoting the development of related industries. Summary of the invention

[0005] The present invention aims to provide a continuous production method and a passivation device based on silicone oil atomization passivation of lime particles, which utilizes an ejector mixer to fully and evenly mix the atomized silicone oil with fluidized lime particles to achieve efficient passivation treatment of the surface of the lime particles, thereby significantly improving its moisture resistance and fluidity, and meeting the requirements of large-scale continuous production.

[0006] In order to achieve the above purpose, the technical solution adopted in this application is: A passivation device based on continuous production of silicone oil atomized passivated lime particles, characterized in that it comprises a fluidized reactor shell, the top of the right side of the fluidized reactor shell is fixedly connected to a mainstream air pipe, and the bottom of the right side of the fluidized reactor shell is fixedly connected to a fluidizing air pipe; the top of the left side of the fluidized reactor shell is fixedly connected to a feed inlet; the top of the fluidized reactor shell is fixedly connected to an exhaust port; the bottom of the fluidized reactor shell is fixedly connected to a mixing tube equipped with an ejector; the bottom end of the mixing tube is connected to a storage bin; One end of the mainstream air pipe extending into the fluidized reactor shell is fixedly connected and integrally formed with a lobe nozzle, the lobe nozzle is fixedly connected with an air collecting hood, and the opening of the air collecting hood is arranged vertically downward; the air collecting hood is arranged above the mixing tube; the middle part of the side of the mixing tube is fixedly connected to the inner wall of the fluidized reactor shell through an air distribution plate; the right side of the fluidized reactor shell is also fixedly connected with a silicone oil delivery pipe, the silicone oil delivery pipe passes through the right side of the fluidized reactor shell and one end of the lobe nozzle and is fixedly connected with a center cone composed of at least one silicone oil nozzle array, the cone tip at the bottom of the center cone is level with the bottom outlet of the lobe nozzle; the other end of the silicone oil delivery pipe is connected to a silicone oil metering pump.

[0007] Preferably, a weighing sensor is fixedly connected to the bottom surface of the fluidized reactor shell; and the weighing sensor is electrically connected to a weighing belt conveyor.

[0008] Preferably, a thermocouple is provided through and fixedly connected between the right side surface of the fluidized reactor shell and the mixing tube, and the thermocouple is electrically connected to an electric heater.

[0009] Preferably, the lobe nozzle has eight lobes, with a lobe height of 50 mm and a lobe inclination angle of 25°; the central cone has a cone angle of 20° and a cone bottom diameter of 100 mm.

[0010] Preferably, the bottom end of the mixing tube is fixedly connected to a diffusion tube; the area ratio of the ejector built into the mixing tube is 4, and the length-to-diameter ratio of the mixing tube is 5; the length of the diffusion tube is 2 to 4 times the diameter of the mixing tube.

[0011] Preferably, the specific passivation operation of the continuous production device is as follows: 1. Turn on the bag filter; 2. Peel the weighing sensor, start the weighing belt conveyor, and add the lime particles into the fluidized reactor shell from the feed port; 3. After the addition is completed, open the fluidizing air pipe valve to input fluidizing air into the fluidized reactor shell for 10 minutes to make the bed uniform and stable; 4. Turn on the silicone oil metering pump and open the mainstream gas pipe to connect the mainstream gas; 5. Under the control of the PID controller, the weighing belt conveyor automatically replenishes materials according to the feedback of the weighing sensor, the silicone oil metering pump adjusts the oil supply, and the mainstream gas pipe adjusts the mainstream gas flow; the electric heater heats the thermocouple to maintain the temperature between 195-210℃.

[0012] A continuous production method based on silicone oil atomization passivation lime particles, the specific production method is as follows: Step 1: Lime fluidization: The lime particles are fluidized by the passivation device of the fluidized bed system; the fluidizing air operating flow rate is 0.6m / s; Step 2: Silicone oil atomization: The silicone oil is atomized into tiny droplets through a centrifugal high-pressure atomization nozzle, and the atomized silicone oil particle size is 10-50um; Step 3: Ejection mixing: Use an ejector to inject fluidized lime, and at the same time, spray silicone oil into the mainstream gas near the bottom outlet of the lobe nozzle, so that the silicone oil droplets and lime particles are quickly mixed in the mixing tube; Step 4: Passivation reaction: The lime particles added later catch up with the silicone oil droplets added earlier, and the two collide and combine together to form an oil film on the surface of the lime particles, completing the passivation; Step 5: Finished product collection: The passivated lime particles fall into the storage bin along the mixing pipe and diffusion pipe for standby use.

[0013] Compared with the prior art, the advantages and positive effects of the present invention are: The present application discloses a continuous production method and a passivation device based on silicone oil atomization passivation of lime particles; the lime particles are first fluidized in a fluidized bed device, the feeding is ensured to be stable by a weighing sensor and a PID controller, and a bag filter is used to treat the exhaust gas; the silicone oil is then atomized in proportion; the atomized silicone oil is then mixed with the fluidized lime particles by an ejector in a mixing tube, the mixing effect is optimized by a structure such as a central cone, and the gas temperature is controlled; the two collide and combine in the mixing tube to complete the passivation; and the finished product is finally collected; the invention can achieve efficient passivation of the surface of the lime particles, improve their moisture resistance and fluidity, can be produced continuously, and is energy-saving, environmentally friendly, and easy to operate; at the same time, a sealing cover and an exhaust pipe are provided at the feeding port to connect to the bag filter, which effectively solves the problem of exhaust gas escape during the feeding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0015] Figure 1 It is a schematic structural diagram of the passivation device of the present invention; In the above figures, 1. fluidized reactor shell; 2. mainstream air pipe; 3. fluidizing air pipe; 4. feed port; 5. exhaust port; 6. mixing tube; 7. lobe nozzle; 8. air collecting hood; 9. air distribution plate; 10. silicone oil delivery pipe; 11. center cone; 12. weighing sensor; 13. thermocouple; 14. diffusion tube. DETAILED DESCRIPTION

[0016] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0017] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0018] Embodiment 1, as Figure 1 As shown, a passivation device for continuous production of silicone oil atomized passivated lime particles of the present application comprises a fluidized reactor shell 1. In the present embodiment, the inner diameter of the shell of the fluidized reactor 1 is 1600 mm; the top of the right side of the fluidized reactor shell 1 is fixedly connected with a mainstream air pipe 2, and the bottom of the right side of the fluidized reactor shell 1 is fixedly connected with a fluidizing air pipe 3; the top of the left side of the fluidized reactor shell 1 is fixedly connected with a feed port 4; the top surface of the fluidized reactor shell 1 is fixedly connected with an exhaust port 5; the bottom surface of the fluidized reactor shell 1 is fixedly connected with a mixing pipe 6 equipped with an ejector; wherein the mainstream air pipe 2, the fluidizing air pipe 3, the feed port 4, the exhaust port 5 and the outer side of the mixing pipe 6 are all fixedly installed with valves; the bottom end of the mixing pipe 6 is connected to a storage bin; One end of the mainstream air pipe 2 extending into the fluidized reactor shell 1 is fixedly connected and integrally formed with a lobe nozzle 7, and the lobe nozzle 7 is fixedly connected with an air collecting hood 8, and the opening of the air collecting hood 8 is arranged vertically downward; specifically, the middle part of the outer side surface of the lobe nozzle 7 is fixedly connected to the top of the air collecting hood 8, and the outlet of the lobe nozzle 7 extends into the air collecting hood 8; the air collecting hood 8 is arranged above the mixing tube 6; the middle part of the side surface of the mixing tube 6 is fixedly connected to the inner wall of the fluidized reactor shell 1 through an air distribution plate 9; the opening rate of the air distribution plate 9 is 5% to 10%, and the aperture is 1-2mm; the distance between the lower edge of the air collecting hood 8 and the air distribution plate 9 is 700mm, and the distance between the upper edge of the mixing tube 6 and the air distribution plate 9 is 1100mm; The right side of the fluidized reactor shell 1 is also fixedly connected to a silicone oil delivery pipe 10, which passes through the right side of the fluidized reactor shell 1 and one end of the lobe nozzle 7 is fixedly connected to a central cone 11 composed of at least one silicone oil nozzle array, and the cone tip at the bottom end of the central cone 11 is level with the bottom outlet of the lobe nozzle 7; the other end of the silicone oil delivery pipe 10 is connected to a silicone oil metering pump; The bottom surface of the fluidized reactor shell 1 is fixedly connected with a weighing sensor 12; the weighing sensor 12 is electrically connected with a weighing belt conveyor; A thermocouple 13 is provided and fixedly connected between the right side of the fluidized reactor shell 1 and the mixing tube 6, and the thermocouple 13 is electrically connected to an electric heater; during use, the electric heater is adjusted according to the feedback of the thermocouple 13 to maintain the temperature near the inlet of the mixing tube 6 at 200-210°C; the electric heater is also connected to the inlet of the mainstream air pipe 2, and the electric heater heats the mainstream air in the mainstream gas pipe 2 to 350°C before entering the lobe nozzle 7; The lobe nozzle 7 has eight lobes, with a lobe height of 50 mm and a lobe inclination of 25°. In this embodiment, in order to make the temperature near the thermocouple 13 slightly lower than 200°C, the air temperature at the lobe nozzle is about 350°C, and the speed is 1900Nm 3 / h of air is ejected from the lobe nozzle at a speed of 100m / s at a working condition of 350°C, then the equivalent circle diameter of the nozzle throat is 110mm; the cone angle of the central cone 11 is 20°, and the cone bottom diameter is 100mm; The bottom end of the mixing tube 6 is fixedly connected with a diffusion tube 14; the area ratio of the ejector built into the mixing tube 6 is 4, and the length-diameter ratio of the mixing tube 6 is 5; in this embodiment, the diameter of the mixing tube 6 is 220 mm and the length is 1100 mm; the length of the diffusion tube 14 is 2 to 4 times the diameter of the mixing tube 6; in this embodiment, the length of the diffusion tube 14 is 500 mm; the diameter of the diffusion tube 14 at the connection with the mixing tube 6 is the same, and the outlet diameter of the bottom end of the diffusion tube 14 is 20% to 50% larger than the inlet diameter. In this embodiment, the diameter of the diffusion tube 14 at the outlet is 260 mm; The specific passivation operation of continuous production equipment is as follows: 1. Turn on the bag filter; 2. Peel the weighing sensor 12, start the weighing belt conveyor, and add the lime particles into the fluidized reactor shell 1 from the feed port 4; stop adding when the feeding amount reaches 1354 kg; 3. After the feeding is completed, open the valve of the fluidizing air pipe 3 and input fluidizing air into the fluidized reactor shell 1 for 10 minutes to make the bed uniform and stable; 4. Turn on the silicone oil metering pump. The initial oil supply of the silicone oil metering pump is 3kg / h. Open the mainstream gas pipe 2 to connect the mainstream gas. The initial flow rate of the mainstream gas is 1900Nm 3 / h; 5. Under the control of the PID controller, the weighing belt conveyor automatically refills the material according to the feedback of the weighing sensor 12; ensure that the total weight of lime in the fluidized reactor shell 1 is maintained at 1324-1384kg, the silicone oil metering pump follows the real-time feeding amount of the weighing belt conveyor to adjust the oil supply according to 3‰ of the weight, and the mainstream gas pipe 2 is adjusted according to the error between the real-time feeding amount of the weighing belt conveyor and the given 1000kg / h processing capacity within 1900Nm 3 / h±5% to adjust the mainstream gas flow; the electric heater heats the thermocouple 13 to adjust the output power according to the feedback of the thermocouple, and the temperature is maintained between 195-210℃; this temperature range avoids the thermal decomposition of silicone oil; according to the physical and chemical properties of the silicone oil used, this temperature value can be appropriately adjusted.

[0019] A continuous production method based on silicone oil atomization passivation lime particles, the specific production method is as follows: Step 1: Lime fluidization: The lime particles are fluidized through the passivation device of the fluidized bed system; the static bed height is 500mm, the porosity is 0.5, the particle size of the lime particles is 0.5-2mm, the processing capacity is 500-2500 kg / h, and the fluidizing air operating flow rate is 0.6m / s; Step 2: Silicone oil atomization: The silicone oil is atomized into tiny droplets through a centrifugal high-pressure atomization nozzle, and the atomized silicone oil particle size is 10-50um; Step three: Injection mixing: Use an ejector to eject fluidized lime, and at the same time, spray silicone oil into the mainstream gas near the bottom outlet of the lobe nozzle 7. The lobe nozzle 7 generates strong flow vortex and shear layer disturbance at the fluid interface. This vortex effect can quickly break the fluid stratification and shorten the distance required for mixing; so that the silicone oil droplets and lime particles are quickly mixed in the mixing tube; wherein, the ejector of the mixing tube 6 is a lobe ejector, and the lobe ejector ejects the surrounding fluid with solid particles through the high-speed mainstream. The presence of the central cone 11 can form a local low-pressure area, further enhancing the ejection effect, and significantly increasing the mass flow rate of the secondary flow involved in the mixing, which is suitable for high particle load scenarios; at the same time, in this process, the central cone 11 optimizes the distribution of the core airflow, reduces the velocity gradient, and makes the solid particles more evenly dispersed in the airflow. Its conical structure can also guide the peripheral fluid to converge to the center to avoid particles gathering at the edge; In addition, when silicone oil is used to passivate small particles of lime, the purpose of heating is to promote the reaction between silicone oil and the surface of lime particles and to ensure that the silicone oil can evenly cover the surface of the particles. The specific reasons are as follows: ① Improve the fluidity of silicone oil: Silicone oil may be relatively viscous at room temperature. Heating can reduce its viscosity, making it easier to flow and diffuse, thereby better covering the surface of lime particles; ② Promote chemical reactions: The siloxane groups in silicone oil may react with the hydroxyl-OH on the surface of lime particles to form chemical bonds. Heating can provide sufficient energy to promote these reactions, thereby enhancing the bonding between silicone oil and lime particles; ③ Uniform coverage: Heating helps the silicone oil to be evenly distributed on the surface of lime particles, avoiding local over-thickness or over-thinness, and ensuring the consistency of the passivation effect; Step 4: Passivation reaction: Since the ejector is installed vertically, with the inlet at the top and the outlet at the bottom, the silicone oil droplets and the lime particles are evenly mixed in the mixing tube 6, and due to the difference in size and density of the two substances, there is a speed difference; at this time, the lime particles added later catch up with the silicone oil droplets added earlier, and the two collide and combine together to form an oil film on the surface of the lime particles, completing the passivation; Step 5: Finished product collection: The passivated lime particles fall into the storage bin along the mixing pipe 6 and the diffusion pipe 14 for standby use; the excess gas in the storage bin is filtered by the bag filter and then discharged, so that a slight negative pressure is maintained in the storage bin to prevent dust from overflowing.

[0020] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A passivation device based on continuous production of silicone oil atomized passivated lime particles, characterized in that: The fluidized reactor shell (1) comprises a main flow air pipe (2) fixedly connected to the top of the right side of the fluidized reactor shell (1), and a fluidizing air pipe (3) fixedly connected to the bottom of the right side of the fluidized reactor shell (1); a feed port (4) fixedly connected to the top of the left side of the fluidized reactor shell (1); an exhaust port (5) fixedly connected to the top of the fluidized reactor shell (1); a mixing pipe (6) equipped with an ejector fixedly connected to the bottom of the fluidized reactor shell (1); and a bottom end of the mixing pipe (6) connected to a storage bin; One end of the mainstream air pipe (2) extending into the fluidized reactor shell (1) is fixedly connected to and integrally formed with a lobe nozzle (7), the lobe nozzle (7) is fixedly connected to an air collecting hood (8), the opening of the air collecting hood (8) being arranged vertically downward; the air collecting hood (8) is arranged above the mixing pipe (6); the middle part of the side of the mixing pipe (6) is fixedly connected to the inner wall of the fluidized reactor shell (1) via an air distribution plate (9); the right side of the fluidized reactor shell (1) is also fixedly connected to a silicone oil delivery pipe (10), the silicone oil delivery pipe (10) passes through the right side of the fluidized reactor shell (1) and one end of the lobe nozzle (7) is fixedly connected to a center cone (11) composed of at least one silicone oil nozzle array, the bottom cone tip of the center cone (11) is level with the bottom outlet of the lobe nozzle (7); the other end of the silicone oil delivery pipe (10) is connected to a silicone oil metering pump.

2. A passivation device based on continuous production of silicone oil atomized passivated lime particles according to claim 1, characterized in that: A weighing sensor (12) is fixedly connected to the bottom surface of the fluidized reactor shell (1); the weighing sensor (12) is electrically connected to a weighing belt conveyor.

3. A passivation device based on continuous production of silicone oil atomized passivated lime particles according to claim 1, characterized in that: A thermocouple (13) is provided through and fixedly connected between the right side surface of the fluidized reactor shell (1) and the mixing tube (6), and the thermocouple (13) is electrically connected to an electric heater.

4. A passivation device based on continuous production of silicone oil atomized passivated lime particles according to claim 1, characterized in that: The lobe nozzle (7) is provided with eight lobes, with a lobe height of 50 mm and a lobe inclination angle of 25°; the cone angle of the central cone (11) is 20°, and the cone bottom diameter is 100 mm.

5. A passivation device based on continuous production of silicone oil atomized passivated lime particles according to claim 1, characterized in that: The bottom end of the mixing tube (6) is fixedly connected to a diffusion tube (14); the area ratio of the ejector built into the mixing tube (6) is 4, and the length-to-diameter ratio of the mixing tube (6) is 5; and the length of the diffusion tube (14) is 2 to 4 times the diameter of the mixing tube (6).

6. A passivation device based on continuous production of silicone oil atomized passivated lime particles according to any one of claims 1 to 5, characterized in that: The specific passivation operation of the continuous production device is as follows:

1. Turn on the bag filter; 2. Peel the weighing sensor (12), start the weighing belt conveyor, and add the lime particles into the fluidized reactor shell (1) from the feed inlet (4); 3. After the addition is completed, open the valve of the fluidizing air pipe (3) and input fluidizing air into the fluidized reactor shell (1) for 10 minutes to make the bed uniform and stable; 4. Turn on the silicone oil metering pump and open the mainstream gas pipe (2) to connect the mainstream gas; 5. Under the control of the PID controller, the weighing belt conveyor automatically replenishes materials according to the feedback of the weighing sensor (12), the silicone oil metering pump adjusts the oil supply, and the mainstream gas pipe (2) adjusts the mainstream gas flow; the electric heater heats the thermocouple (13) to maintain the temperature between 195-210°C.

7. A continuous production method based on silicone oil atomization passivation lime particles according to claim 6, characterized in that: The specific production method is as follows: Step 1: Lime fluidization: The lime particles are fluidized by the passivation device of the fluidized bed system; the fluidizing air operating flow rate is 0.6m / s; Step 2: Silicone oil atomization: The silicone oil is atomized into tiny droplets through a centrifugal high-pressure atomization nozzle, and the atomized silicone oil particle size is 10-50um; Step 3: Injection mixing: Use an ejector to inject fluidized lime, and at the same time, inject silicone oil into the mainstream gas near the bottom outlet of the lobe nozzle (7), so that the silicone oil droplets and lime particles are quickly mixed in the mixing tube; Step 4: Passivation reaction: The lime particles added later catch up with the silicone oil droplets added earlier, and the two collide and combine together to form an oil film on the surface of the lime particles, completing the passivation; Step 5: Finished product collection: The lime particles that have been passivated fall into the storage bin along the mixing pipe (6) and the diffusion pipe (14) for later use.

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