Anti-fouling high viscosity material explosion-proof stirring vacuum drying kettle, drying method, packing system and packing method

Abstract

The present application relates to the technical field of chemical equipment, in particular to a kind of anti-blowing mixing vacuum drying kettle of anti-fouling high viscosity material, drying method, packing system and packing method.The drying kettle includes vacuum drying kettle assembly, combined anti-fouling stirring assembly, system-level explosion-proof assembly and intelligent control system.Vacuum drying kettle assembly includes kettle body with heating jacket, combined anti-fouling stirring assembly includes stirring spindle, stirring unit, wall scraping stirring frame and scraper unit, system-level explosion-proof assembly includes explosion-proof drive motor, magnetic coupling transmission device, anti-static grounding system and nitrogen sealing protection system, and intelligent control system includes controller and torque sensor.Vacuum drying kettle assembly, combined anti-fouling stirring assembly and system-level explosion-proof assembly form an explosion-proof stirring vacuum environment, and the intelligent control system constructs closed-loop adaptive control logic.The present application solves the technical problems of high viscosity material fouling, explosion safety and drying and packing integration.

Description

Technical Field

[0001] This invention relates to the field of chemical equipment technology, specifically to an explosion-proof stirring vacuum drying kettle for high-viscosity materials with anti-scaling properties, a drying method, a packaging system, and a packaging method. Background Technology

[0002] In the fields of fine chemicals, pharmaceuticals, and new materials, there are a large number of high-viscosity, heat-sensitive, flammable and explosive materials (such as energetic intermediates, polymer precursors, rubber additives, and pharmaceutical intermediates) that require vacuum drying. The viscosity of these materials changes significantly with temperature and humidity, they are prone to scaling on heated walls, and the volatile solvents can easily create an explosive environment, placing stringent requirements on drying equipment.

[0003] Existing vacuum drying equipment has several technical shortcomings when used for processing high-viscosity flammable materials, failing to meet the demands for safe and efficient processing: First, its ability to prevent scaling on the vessel wall is weak. Traditional rigid scraping structures experience increased gaps due to long-term wear, allowing high-viscosity materials to easily adhere to the vessel wall and form scale. This not only reduces heat exchange and drying efficiency and increases energy consumption, but high-temperature scaling can also easily pyrolyze and generate gas, posing a risk of combustion and explosion. Second, its explosion-proof design is fragmented and unsystematic. Friction at the mechanical seals at the equipment shaft ends can easily generate hot spots and ignite; wear can easily lead to leakage of flammable solvents; and material stirring can easily accumulate static electricity. Existing equipment only uses single-point explosion-proof measures such as nitrogen protection and explosion-proof motors, without combining sealing, static electricity, and atmosphere dimensions to build a systematic explosion-proof structure, resulting in insufficient operational safety. Third, the integration of processes is poor. After drying, materials need to be transferred and packaged in an open, vacuum-sealed manner. Materials are prone to moisture absorption and oxidation, and open operations pose high safety risks. Furthermore, manual operation can easily cause material contamination and inaccurate measurement. Fourth, it lacks intelligent adaptive control. The viscosity of materials changes dynamically during the drying process. Existing equipment has fixed process parameters, which cannot be adapted to the material state adjustment conditions, and is prone to problems such as motor overload, material pyrolysis, and equipment damage.

[0004] To address the aforementioned technical deficiencies, patent CN101571344B discloses a vacuum mixing and drying unit. However, its frame-type rigid scraper cannot compensate for the increased clearance caused by blade wear, resulting in a continuous deterioration in its anti-scaling effect over long-term operation. Furthermore, this solution lacks explosion-proof design and automatic packaging functionality. Patent CN118508707A discloses a magnetic coupling transmission sealing structure, but there is a long-standing technical bias in this field: magnetic transmission is only suitable for low-viscosity, low-torque conditions. Under the high-torque conditions required for stirring high-viscosity materials, magnetic transmission is prone to slippage failure, forcing high-viscosity stirring equipment to still rely on mechanical seals that are prone to frictional heat generation and media leakage. The explosion-proof vacuum drying oven disclosed in patent CN216694219U is a static drying device without a stirring structure, thus failing to meet the drying requirements of high-viscosity materials.

[0005] Therefore, it is necessary to provide an integrated solution that can simultaneously address the four major technical challenges of preventing scaling of high-viscosity materials, system-level explosion protection, integrated drying and packaging, and intelligent adaptive control to solve the aforementioned technical problems. Summary of the Invention

[0006] The purpose of this invention is to provide an explosion-proof stirring vacuum drying kettle, drying method, packaging system and packaging method for high-viscosity materials that prevents scaling, aiming to solve the technical problems of severe scaling, insufficient explosion-proof safety, disconnect between drying and packaging processes, and lack of intelligent control in existing high-viscosity materials.

[0007] To achieve the above objectives, the present invention provides an explosion-proof stirring vacuum drying kettle for high-viscosity materials with anti-scaling properties, comprising a vacuum drying kettle assembly, a combined anti-scaling stirring assembly, a system-level explosion-proof assembly, and an intelligent control system. The vacuum drying autoclave assembly includes an autoclave body with a heating jacket. The autoclave body includes an upper cylindrical section and a lower conical section arranged in series. The upper cylindrical section has a feed inlet, a vacuum port, and a nitrogen inlet at its upper part, and the lower conical section has a discharge port at its lower part. The feed inlet is used to add the material to be dried into the autoclave body. The vacuum port is connected to a vacuum pump for evacuating the autoclave body. The discharge port is used to discharge the dried material. The heating jacket is equipped with a heating source. The combined anti-scaling stirring assembly includes a stirring spindle, a stirring unit, a wall-scraping stirring frame, and a scraper unit. Both the stirring unit and the wall-scraping stirring frame are rotatably mounted on the stirring spindle, and the stirring unit and the wall-scraping stirring frame have opposite spiral directions to form a three-dimensional circulating flow field. The scraper unit is mounted on the wall-scraping stirring frame to prevent scaling on the inner wall of the vessel. The system-level explosion-proof components include an explosion-proof drive motor, a magnetic coupling transmission device, an anti-static grounding system, and a nitrogen sealing protection system. The stirring spindle is connected to the explosion-proof drive motor via the magnetic coupling transmission device. The anti-static grounding system includes a conductive structural component installed on the scraper unit. The conductive structural component is electrically connected to the grounding copper busbar through the scraper stirring frame and the stirring spindle to form an electrostatic discharge path. The nitrogen sealing protection system includes a gas supply pipe, a valve, and an oxygen content detector. The gas supply pipe connects to the gas source and the nitrogen inlet. A valve is installed on the gas supply pipe, and the oxygen content detector is used to detect the oxygen content of the vessel. The intelligent control system includes a controller and a torque sensor. The torque sensor is installed on the stirring spindle to obtain the rotational speed and torque signals of the stirring spindle. The torque sensor, oxygen content detector, heating source, vacuum device, explosion-proof drive motor, and valves are all connected to the controller.

[0008] Preferably, the controller includes an input module, a processing module, and an output module; Both the torque sensor and the oxygen content detector are connected to the input module; The heating source, vacuum device, explosion-proof drive motor, and valves are all connected to the output module. The processing module has a built-in viscosity estimation algorithm. It calculates and judges the viscosity of the material based on the stirring speed and torque signals obtained by the input module. Specifically, when the viscosity of the material exceeds the first set threshold, the output module controls the explosion-proof drive motor to reduce the stirring speed and controls the heating source to increase the temperature of the heating jacket. When the viscosity of the material exceeds the second set threshold, the output module controls the explosion-proof drive motor to realize the intermittent forward and reverse operation of the stirring spindle.

[0009] Preferably, the processing module also incorporates a correlation formula for the stirring power coefficient, as follows: ; in: For power parameters, , This refers to the actual stirring power. , This refers to the stirring speed. The stirring torque is collected by a torque sensor. For material density, The diameter of the vessel body; It is the Reynolds number; and These are pre-calibrated empirical constants; Viscosity of the material Calculate using the following formula: ; The first set threshold is 50,000 to 150,000 mPa·s, and the second set threshold is 150,000 to 300,000 mPa·s; the empirical constant in the power metric correlation. The value range is from 50 to 200, an empirical constant. The value ranges from -1.2 to -0.8. The empirical constant is obtained by calibration experiments using standard silicone oil of known viscosity at speeds ranging from 5 rpm to 60 rpm.

[0010] Preferably, the stirring unit includes an inner spiral agitator and a bottom anchor paddle. The inner spiral agitator is located inside the upper cylindrical section and has a wall-scraping stirring frame on its outer side. The spiral directions of the inner spiral agitator and the wall-scraping stirring frame are opposite, forming a three-dimensional circulating flow field. The bottom anchor paddle is located inside the lower conical section.

[0011] Preferably, the scraper unit includes multiple sets of elastic scraper assemblies mounted on the wall-scraping stirring frame; The elastic scraper assembly includes a scraper seat, an elastic clamping mechanism, and a scraper blade. The scraper seat is disposed on the wall-scraping stirring frame, and the scraper blade is disposed on the scraper seat through the elastic clamping mechanism. The elastic clamping mechanism enables the scraper blade to always adhere tightly to the inner wall of the vessel under the action of elastic force, adaptively compensating for scraper blade wear and vessel wall deformation.

[0012] Preferably, the magnetic coupling transmission device includes an outer magnetic rotor, an inner magnetic rotor, and a non-magnetic isolation cover that is sealed to the flange at the top of the vessel, achieving a completely static sealed transmission of the stirring shaft; both the outer and inner magnetic rotors use neodymium iron boron rare earth permanent magnets with no less than 6 pairs of magnetic poles and a rated transmission torque of no less than 2000 N·m; the non-magnetic isolation cover is a cylindrical body made of titanium alloy or Hastelloy with a wall thickness of 3 to 6 mm; the outer magnetic rotor is provided with a forced air-cooled shield to dissipate the heat generated by the eddy currents.

[0013] This invention also discloses a material drying method, which uses the above-mentioned anti-scaling, high-viscosity material explosion-proof stirring vacuum drying kettle for drying, including the following steps: Step 1, Feeding and Atmosphere Replacement: The material enters the reactor body through the feed port. The nitrogen sealing protection system is started to perform at least three vacuuming-nitrogen filling cycles on the reactor body. Each time, after vacuuming to an absolute pressure of no more than 5 kPa, nitrogen is filled to a slightly positive pressure to reduce the oxygen content inside the reactor body to below 2%. Step 2, heating and stirring drying: Turn on the heating source to heat the heating jacket, set the temperature of the upper cylindrical section to 60℃ to 120℃ and the temperature of the lower conical section to 80℃ to 150℃, and start the stirring spindle to run at a speed of 5rpm to 60rpm. Turn on the vacuum system to maintain the absolute pressure inside the vessel within the range of 1kPa to 20kPa. Step 3, Intelligent Adaptive Control: The intelligent control system collects the stirring torque in real time through a torque sensor and calculates the viscosity of the material based on the power coefficient correlation formula. When the viscosity of the material exceeds the first set threshold, it automatically reduces the stirring speed by 20% to 50% and increases the temperature of the lower cone section by 5°C to 15°C. When the viscosity of the material exceeds the second set threshold, it controls the stirring spindle to perform intermittent forward and reverse rotation operations according to a cycle of 20 to 30 seconds forward rotation, 3 to 5 seconds stop, and 20 to 30 seconds reverse rotation. Step 4: The dried material is output through the discharge port.

[0014] The present invention also discloses a packaging system comprising the above-mentioned anti-scaling, explosion-proof stirring vacuum drying kettle for high-viscosity materials, and further comprising: A sealed transition and conveying assembly, connected to the outlet of the vessel, includes, in sequence, a discharge ball valve, a star-shaped discharge valve, a vacuum transition chamber, and a shaftless screw conveyor; the gap between the rotor blades of the star-shaped discharge valve and the shell is no greater than 0.1 mm; the vacuum transition chamber is provided with an independent vacuum port and a nitrogen inlet, the vacuum port being connected to a vacuum pumping device; the nitrogen inlet is connected to a nitrogen source through a pipeline. The automatic packaging assembly, connected to the outlet of the shaftless screw conveyor, includes a buffer hopper, a metering and weighing unit, an automatic bag making and filling machine, and a nitrogen-filling heat-sealing unit.

[0015] Preferably, the star-shaped discharge valve is equipped with a steam heating jacket to maintain the valve body temperature within the range of 40°C to 80°C to prevent material solidification; the shaftless screw conveyor is equipped with a heat tracing and insulation sleeve to maintain the conveying temperature within the range of 50°C to 90°C.

[0016] The present invention also discloses a packaging method, which realizes packaging based on the above-mentioned packaging system, specifically including: opening the discharge ball valve and the star-shaped discharge valve in sequence, the material output through the discharge port enters the shaftless screw conveyor through the vacuum transition chamber, is transported to the buffer hopper of the automatic packaging component, is filled by the automatic bag making and filling machine after metering and weighing, and finally the nitrogen filling heat sealing unit completes the heat sealing packaging under nitrogen protection.

[0017] Compared with the prior art, the present invention has the following advantages: First, the anti-scaling effect is significant and long-lasting. The combined anti-scaling stirring assembly of this invention includes a stirring shaft, a stirring unit, a wall-scraping stirring frame, and a scraper unit. The stirring unit and the wall-scraping stirring frame have opposite spiral directions, forming a three-dimensional circulating flow field, eliminating dead zones in the material flow within the vessel. The combination of the elastic clamping mechanism and the high-temperature resistant special engineering plastic scraper ensures that the scraper blade remains in close contact with the vessel wall throughout its entire service life.

[0018] Secondly, the system offers high explosion-proof safety. This invention utilizes neodymium iron boron permanent magnets, optimizes the magnetic circuit design, and increases the number of pole pairs, achieving contactless transmission of high torque exceeding 2000 N·m, eliminating the frictional heat generation and leakage risks associated with traditional mechanical seals. Simultaneously, the conductive carbon fiber network embedded in the antistatic scraper material and the complete grounding path ensure timely dissipation of static electricity generated during stirring, while full-process nitrogen protection controls the oxygen content within the system to below 2%. These three elements work together to construct a system-level explosion-proof system encompassing sealing, static electricity, and atmosphere protection.

[0019] Third, the drying and packaging processes are fully integrated in a sealed system. This invention achieves seamless integration between the vacuum drying autoclave and the automatic packaging system through a combination of a star-shaped discharge valve, a vacuum transition chamber, and a shaftless screw conveyor. The entire process, from drying to packaging and sealing, is completed in a sealed, nitrogen-protected environment, avoiding moisture absorption, oxidation, and safety risks caused by material contact with air. It also eliminates contamination and measurement errors resulting from manual operation.

[0020] Fourth, it boasts a high degree of intelligence. The intelligent control system of this invention achieves online real-time estimation of material viscosity based on power metric correlation, overcoming the shortcomings of traditional online viscometers, such as easy damage and inaccurate measurements under high-temperature and high-viscosity conditions. The dual-threshold adaptive control logic, built based on the viscosity estimation results, can automatically adjust the stirring speed, heating temperature, and stirring direction according to real-time changes in the material's state, effectively preventing equipment overload and localized overheating, optimizing drying process parameters, and reducing energy consumption. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the anti-scaling, explosion-proof stirring vacuum drying kettle and packaging system for high-viscosity materials according to the present invention. Figure 2 This is a schematic diagram of the combined anti-scaling stirring assembly of the present invention; Figure 3 This is a partially enlarged schematic diagram of the elastic scraper assembly of the present invention; Figure 4 This is a cross-sectional view of the magnetic coupling transmission device of the present invention; Figure 5 This is a schematic diagram of the structure of the sealed transition and conveying assembly of the present invention; Figure 6 This is a control logic block diagram of the intelligent control system of the present invention; Explanation of markings in the diagram: 1-Explosion-proof drive motor; 2-Magnetic coupling transmission device; 3-Vat body; 4-Heating jacket; 5-Stirring shaft; 6-Internal spiral agitator; 7-Wall scraping agitator frame; 8-Elastic scraper assembly; 9-Bottom anchor paddle; 10-Discharge ball valve; 11-Star discharge valve; 12-Vacuum transition chamber; 13-Shaftless screw conveyor; 14-Automatic packaging assembly; 15-Nano-PTFE anti-stick coating; 21-External magnetic rotor; 22-Internal magnetic rotor; 23-Non-magnetic isolation cover; 24-Metal spiral wound gasket; 25-Grounding carbon brush; 26-Forced air cooling cover; 31-Upper cylindrical section; 32-Lower conical section; 33-Feed inlet; 41-Upper cylindrical heating zone; 42-Lower conical heating zone; 71-Connecting arm; 81-Scraper seat; 82-Elastic clamping mechanism; 83-Scraper blade; 84-Conductive carbon fiber network; 111-Steam tracing jacket; 121-Vacuum port; 122-Nitrogen inlet; 131-Spiral blade; 132-Ultra-high molecular weight polyethylene inner liner; 133-Heating and insulation sleeve; 141-Buffer hopper; 142-Measuring and weighing unit; 143-Automatic bag making and filling machine; 144-Nitrogen-filled heat sealing unit. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0024] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0025] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0026] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0027] This invention provides an explosion-proof stirring vacuum drying kettle for high-viscosity materials with anti-scaling properties, a drying method, a packaging system, and a packaging method, aiming to solve existing technical problems such as severe scaling of high-viscosity materials, insufficient explosion-proof safety, disconnect between drying and packaging processes, and lack of intelligent control.

[0028] Example 1: This embodiment provides an explosion-proof stirring vacuum drying kettle, drying method and packaging system for anti-scaling high viscosity materials, used to process energetic material intermediates (wet nitrocellulose). The initial moisture content of the material is about 35%, and the moisture content at the drying endpoint is ≤0.5%. During the drying process, the viscosity of the material gradually increases from about 5000 mPa·s initially to about 180000 mPa·s.

[0029] This embodiment of the anti-scaling, high-viscosity material explosion-proof stirring vacuum drying kettle includes a vacuum drying kettle assembly, a combined anti-scaling stirring assembly, a system-level explosion-proof assembly, and an intelligent control system. See details... Figures 1-6 The specific structure is as follows: In the vacuum drying autoclave assembly, the autoclave body 3 is made of corrosion-resistant austenitic stainless steel, with a total volume of 6000L and an effective volume of 4000L. It includes an upper cylindrical section 31 and a lower conical section 32 arranged in series. The ratio of the height H1 to the inner diameter D1 of the upper cylindrical section 31 is set to 1.2-1.8; the cone angle of the lower conical section 32 is 45°-60°, and the cone height is 1200-1500mm. The autoclave is designed to withstand a pressure of -0.1 to 0.3MPa and a temperature of 200℃. The inner wall of the autoclave body 3 is first mechanically polished to Ra≤0.8μm, then electrolytically polished to Ra≤0.4μm, and finally coated with a 50μm thick nano-polytetrafluoroethylene anti-stick coating 15 using a plasma spraying process. The coating is composed of polytetrafluoroethylene nanoparticles and an inorganic binder. The inorganic binder can be one or more of silica sol, alumina sol, zirconium sol, aluminum phosphate, or silicate binders, as per existing technology. A heating jacket 4 covers the outer wall of the vessel body 3. An upper cylindrical heating zone 41 and a lower conical heating zone 42 are respectively provided for the upper cylindrical section 31 and the lower conical section 32. The heating area of ​​the upper cylindrical heating zone 41 is 8.0-9.6 m². 2 The heating area of ​​the lower cone heating zone 42 is 4.5-5.8m². 2 The heating source uses a heat transfer oil pipe, and the heat transfer oil used is No. 320 heat transfer oil, preferably with a design flow rate of 22-30 m³ / h. 3 / h, heating power is 75-90kW.

[0030] In the combined anti-scaling stirring assembly, the stirring spindle 5 is made of high-strength duplex stainless steel, with a shaft diameter of 120-140mm and a rotational speed range of 5rpm to 45rpm. The internal spiral ribbon stirrer 6 is a right-handed single-headed spiral ribbon, with the ribbon width and outer diameter being 50% of the inner diameter of the vessel body 3, and the pitch being the same as the inner diameter of the vessel body 3. The wall-scraping stirring frame 7 is a left-handed structure, fixed to the stirring spindle 5 by six connecting arms 71. Twelve sets of elastic scraper assemblies 8 are evenly installed on the outer edge of the wall-scraping stirring frame 7, with the spacing between adjacent scraper assemblies being 285-320mm.

[0031] In the elastic scraper assembly 8, the scraper seat 81 is made of 304 stainless steel and is fixed to the outer edge of the scraper stirring frame 7 by bolts. The elastic clamping mechanism 82 uses a combination of three disc springs connected in series. The specifications of a single disc spring can be preferably: outer diameter 28mm, inner diameter 14mm, thickness 1.5mm, and free height 2.8mm. The total compensation stroke after the three disc springs are connected in series is 4.0-5.5mm, and the elastic clamping force provided is 75-90N. The scraper blade 83 is made of high-temperature resistant special engineering plastic (such as polyetheretherketone and similar materials), with a carbon fiber mass fraction of 30%. The dimensions of the scraper blade 83 are 200mm in length, 50mm in width, and 5mm in thickness. The volume resistivity of the scraper blade 83 is 5×10⁻⁶. 4 Ω·cm, far below 106 The antistatic requirement is Ω·cm. A conductive carbon fiber network 84 is embedded inside the scraper blade 83. This network is woven from continuous carbon fibers with a diameter of 5-8μm and a mesh spacing of 4.5-5.5mm, forming a conductive path with the chopped carbon fibers in the scraper blade 83 matrix. The conductive carbon fiber network 84 is electrically connected to the metal skeleton of the scraper stirring frame 7 through the metal contact surface of the scraper seat 81, and then conducted through the stirring main shaft 5 to the grounding carbon brush 25 at the top of the main shaft, finally connecting to the grounding copper busbar to form a complete electrostatic discharge path. The overall grounding resistance is measured to be 40-60Ω. The shape of the bottom anchor-type paddle 9 matches the inner wall shape of the lower conical section 32, with a blade width of 95-120mm and a gap of 8-16mm between the blade and the inner wall of the cone. During wall scraping operation, the scraper holder 81 rotates synchronously with the wall scraping stirring frame 7. One end of the elastic clamping mechanism 82 is supported on the scraper holder 81, and the other end applies radial preload to the scraper blade 83, ensuring that the scraper blade 83 always adheres to the inner wall of the vessel body 3. When the scraper blade 83 wears or there is a roundness deviation in the inner wall of the vessel body 3, the elastic clamping mechanism 82 compensates for the gap through compression and rebound, driving the scraper blade 83 to move slightly radially, thereby continuously scraping off the wall adhesion layer and maintaining stable contact pressure. The conductive carbon fiber network 84 moves synchronously with the scraper blade 83 and is connected to the electrostatic discharge path through the scraper holder 81 and the wall scraping stirring frame 7.

[0032] In the magnetic coupling transmission device 2, both the outer magnetic rotor 21 and the inner magnetic rotor 22 use neodymium iron boron permanent magnets (grade N50SH), with 8 pairs of magnetic poles (i.e., each of the outer magnetic rotor 21 and the inner magnetic rotor 22 has 16 magnetic tiles). The dimensions of the magnetic tiles are 60mm arc length, 80mm width, and 15mm thickness. The outer diameter of the outer magnetic rotor 21 is 380mm, the outer diameter of the inner magnetic rotor 22 is 320mm, and the air gap (including the wall thickness of the isolation cover) is 12mm. The rated transmission torque is 2500N·m, and the maximum transmission torque is 3200N·m (safety factor 1.28). The non-magnetic isolation cover 23 is made of titanium alloy TC4, with a wall thickness of 4mm, an inner diameter of 340mm, and a length of 200mm. The upper flange of the isolation cover is sealed to the top flange of the vessel body 3 through a metal spiral wound gasket 24. The flange bolt preload is 120kN, the sealing surface pressure is 45MPa, and the leakage rate is less than 1×10⁻⁶. -6 mbar·L / s. The external magnetic rotor 21 is equipped with a forced air-cooled shield 26, with an air volume of 500 m³ / s. 3 / h, ensuring the magnet's operating temperature does not exceed 100℃ (the maximum operating temperature of the N50SH is 150℃, with a 50℃ safety margin). During operation, the explosion-proof drive motor 1 drives the outer magnetic rotor 21 to rotate. The magnetic field of the outer magnetic rotor 21 passes through the non-magnetic isolation cover 23 and magnetically couples with the inner magnetic rotor 22, driving the inner magnetic rotor 22 and the stirring shaft 5 to rotate synchronously. The non-magnetic isolation cover 23 forms a static seal with the top flange of the vessel body 3 through the metal spiral wound gasket 24, completely isolating the motor side from the material side inside the vessel. The grounding carbon brush 25 maintains sliding contact with the stirring shaft 5, conducting the static electricity accumulated in the stirring components to the grounding copper busbar. This linkage transmits torque without dynamic seal penetration points, reducing the risk of leakage and ignition. Its principle is that the attraction / repulsion between the permanent magnet poles forms a synchronous magnetic field coupling, the isolation cover provides a pressure boundary, and the grounding carbon brush 25 provides a low-resistance static discharge channel.

[0033] In the sealed transition and conveying components of the packaging system, the discharge ball valve 10 is a full-bore pneumatic ball valve with a nominal diameter of DN200 and a valve body made of corrosion-resistant alloy. The rotary valve 11 has 8 rotor blades with a diameter of 250mm and a blade-to-shell clearance of 0.08mm. The rotor blades are coated with polytetrafluoroethylene. The rotary valve 11 is equipped with a steam tracing jacket 111, with a steam pressure of 0.3MPa, maintaining the valve body temperature at 60℃ to prevent high-viscosity materials from solidifying within the valve body. The vacuum transition chamber 12 has a volume of 100L and is equipped with an independent vacuum port 121 and a nitrogen inlet 122, maintaining the absolute pressure within the chamber in the range of 5 to 10 kPa during the discharge process. The shaftless screw conveyor 13 has a conveying pipe inner diameter of 200mm, an outer diameter of 190mm for the screw blades, a pitch of 150mm, a thickness of 10mm, and is made of wear-resistant alloy steel. The inner wall of the conveying pipe is lined with an ultra-high molecular weight polyethylene inner liner 132 with a wall thickness of 5 mm and a friction coefficient of only 0.05 to 0.08. The outside of the conveying pipe is equipped with a heat tracing and insulation sleeve 133, which uses electric heating tape to maintain the conveying temperature at 65℃.

[0034] In the automatic packaging component 14 of the packaging system, the buffer hopper 141 has a volume of 200L and is equipped with a vibration arch-breaking device at the bottom. The metering and weighing unit 142 adopts a dual-speed feeding method (fast feeding + precise feeding), with a weighing range of 5 to 50 kg and a weighing accuracy of ±0.2%. The automatic bag making and filling machine 143 adopts a vertical bag making and filling method, with a packaging speed of 3 to 8 bags / minute. The nitrogen filling and heat sealing unit 144 fills the packaging bag with high-purity nitrogen (purity ≥99.99%) before sealing, replacing the air inside the bag before heat sealing. The heat sealing temperature is 160 to 200℃, and the sealing strength is not less than 15N / 15mm.

[0035] In the intelligent control system, the PLC controller is a Siemens S7-1500 series with a scan cycle of 1ms. The torque sensor is installed at the top of the stirring shaft 5, with a range of 0 to 5000 N·m, an accuracy of ±0.1%FS, and a sampling frequency of 100Hz. Temperature sensors are PT100 platinum resistance thermometers, installed at the inlet and outlet of the heating jacket 4 and inside the vessel body 3, with an accuracy of ±0.2℃. The vacuum sensor has a range of 0 to 101.3 kPa (absolute pressure) and an accuracy of ±0.5%FS. The oxygen content detector uses an electrochemical sensor with a range of 0 to 25%, an accuracy of ±0.1%, and a response time of less than 10 seconds. The input terminals of the PLC controller are connected to the torque sensor, temperature sensor, vacuum sensor, and oxygen content detector, respectively. The output terminals are connected to the frequency converter of the explosion-proof drive motor 1, the heat transfer oil circulation and heating execution unit, the vacuum pump, the electromagnetic gas injection valve group, the discharge ball valve 10, the rotary valve 11, the shaftless screw conveyor 13, and the automatic packaging assembly 14, respectively. During the coordinated operation, the PLC controller first performs vacuuming and nitrogen purging based on the oxygen content and vacuum feedback to confirm the safety conditions. Then, it adjusts the temperature of the heating zone and the stirring speed according to the closed-loop feedback of temperature, pressure, and torque. After the drying endpoint is met, the PLC controller issues interlocking action commands in the order of discharge ball valve 10, rotary valve 11, vacuum transition chamber 12, shaftless screw conveyor 13, and automatic packaging assembly 14 to ensure that drying, conveying, metering, and nitrogen heat sealing are completed continuously and in a sealed manner.

[0036] In this embodiment, the empirical constant of the viscosity estimation algorithm module A and B The calibration method steps are as follows: Step s1: Selection and preparation of calibration fluid: Select standard silicone oils with viscosities of 1000, 5000, 20000, 50000, 100000, and 200000 mPa·s as calibration fluids. Heat the silicone oils to the actual process temperature and use a rotational viscometer to measure the actual viscosity value at that temperature as a reference standard.

[0037] Step s2: No-load test: With no material loaded into vessel 3, the calibration fluid is sequentially loaded into vessel 3 and run at nine speeds of 5, 10, 15, 20, 25, 30, 35, 40 and 45 rpm respectively. The steady-state torque value at each speed is recorded. .

[0038] Step s3: Load test: Fill the first type of calibrated silicone oil into reactor 3, run it at the speeds mentioned above, and record the torque value after the torque reading stabilizes. The formula for calculating net stirring torque is as follows: ,in For load testing torque, This is the no-load torque. Repeat this step for all calibrated silicone oils in sequence.

[0039] Step s4: Data calculation and regression fitting: According to the formula Calculate the stirring power under each operating condition, and then based on and Calculate the power number and Reynolds number separately, where: This refers to the actual stirring power. , This refers to the stirring speed. The stirring torque is collected by a torque sensor. For material density, The diameter of vessel body 3 is [missing information]. This refers to the fluid dynamic viscosity or the apparent viscosity of the material. All data points and Plotting the data in a log-log coordinate system and performing linear regression using the least squares method yields the following results. ,Right now The coefficient of determination for regression fit. The value should not be lower than 0.99; otherwise, the experimental data needs to be checked and recalibrated. The value obtained in this embodiment is calculated... =85.6, =-1.05.

[0040] Step s5: Verification and Correction: A verification experiment is conducted using a known viscosity silicone oil (e.g., viscosity 80000 mPa·s) that was not calibrated. Torque is measured at multiple speeds, and the calibrated torque is used as the reference value. and The viscosity is calculated by inverse calculation and compared with the actual viscosity. If the relative error does not exceed ±8%, the calibration result is valid; if the error exceeds the limit, the number of calibration points needs to be increased or the calibration interval needs to be narrowed for refitting.

[0041] The calibration results show that, The goodness of fit of this correlation is within the range of 0.1 to 80 (corresponding to viscosities of approximately 3000 to 200000 mPa·s). =0.994, viscosity estimation error not exceeding ±6%.

[0042] According to the formula and The Reynolds number can be calculated. Then by formula Calculate the apparent viscosity of the material .

[0043] In this embodiment, the first threshold value is set to 80,000 mPa·s, and the second threshold value is set to 150,000 mPa·s. When the intelligent control system detects that the material viscosity exceeds 80,000 mPa·s, it automatically reduces the stirring speed by 30% (e.g., from 30 rpm to 21 rpm) and simultaneously increases the temperature of the lower cone heating zone 42 by 10°C. When the material viscosity exceeds 150,000 mPa·s, the enhanced wall scraping program is activated, and the stirring spindle 5 operates in a cycle of 25 seconds forward rotation, 4 seconds stop, and 25 seconds reverse rotation, using reverse shear force to break the adhesion structure of the material on the wall surface.

[0044] The execution steps of this embodiment are as follows: Step ①: Feeding and Atmosphere Replacement: Pump wet nitrocellulose with a moisture content of approximately 35% into reactor body 3 through feed port 33, with a loading volume of 3500L. Activate the nitrogen sealing protection system to perform at least three vacuum-nitrogen-purging cycles on reactor body 3. After each vacuuming to an absolute pressure of 3kPa, purge with nitrogen to a slightly positive pressure, reducing the oxygen content inside reactor body 3 to below 1.5%.

[0045] Step 2: Heating and stirring drying: Turn on the heating jacket 4, set the temperature of the upper cylindrical heating zone 41 to 85℃ and the temperature of the lower conical heating zone 42 to 95℃, and start the stirring spindle 5 at 30 rpm. Turn on the vacuum system to maintain the absolute pressure inside the vessel at 8 kPa.

[0046] Step 3: Intelligent Adaptive Control: During the drying process, the intelligent control system continuously monitors the stirring torque and estimates the material viscosity. When drying has progressed to approximately 4 hours, the material moisture content drops to approximately 8%, and the estimated viscosity reaches 80,000 mPa·s. The system automatically reduces the rotation speed to 21 rpm and increases the temperature of the lower cone heating zone 42 to 105°C. When drying has progressed to approximately 6 hours, the material moisture content drops to approximately 2%, and the estimated viscosity reaches 150,000 mPa·s. The system then initiates the enhanced wall scraping program. After approximately 8.5 hours of drying, the material moisture content reaches 0.3%, meeting the drying endpoint requirements.

[0047] Step 4: After drying, open the discharge ball valve 10 and the star-shaped discharge valve 11 in sequence. The material enters the shaftless screw conveyor 13 through the vacuum transition chamber 12 and is conveyed to the automatic packaging assembly 14 to complete the quantitative packaging of 25kg / bag and nitrogen heat sealing. The entire discharge and packaging process takes about 45 minutes, and the discharge residue rate is 0.6%.

[0048] In addition to viscosity adaptive control, the intelligent control system of this invention also features multiple safety interlock protection logics to ensure that the equipment can be safely shut down or protective measures can be taken under any abnormal operating conditions.

[0049] Level 1 Interlock: Oxygen Content Over-Limit Protection. When the oxygen content detector detects that the oxygen content in the system exceeds 3%, the intelligent control system immediately issues a Level 1 alarm and automatically increases the nitrogen injection flow rate to 3 times the normal value; when the oxygen content exceeds 5%, the system issues a Level 2 alarm, immediately stops the stirring motor and heating system, and simultaneously opens the emergency nitrogen charging valve to inject nitrogen into the vessel at the maximum flow rate, triggering an audible and visual alarm to notify the operator.

[0050] Second-level interlock: Torque overload protection. When the stirring torque exceeds 120% of the rated torque for more than 10 seconds, the system automatically reduces the stirring speed by 50%; when the torque exceeds 150% of the rated torque, the system immediately stops the stirring motor to prevent slippage of the magnetic coupler or damage to the stirring components. After stopping due to torque overload, the system automatically performs a low-speed reverse operation (5 rpm, lasting 30 seconds) to attempt to unwrap the material from the stirring components, and then restarts at the lowest speed. If all three restarts fail, the stirring function is locked and an alarm is triggered.

[0051] Third-level interlock: Temperature over-limit protection. When the temperature of the material inside the vessel exceeds the set upper limit by 20°C, the system automatically shuts down the heat transfer oil circulation pump in the corresponding heating zone; when the temperature exceeds the set upper limit plus 40°C, the system shuts down all heating and starts cooling water circulation (if equipped), while reducing the stirring speed to reduce frictional heat generation.

[0052] Fourth-level interlock: Vacuum abnormality protection. When the pressure inside the vessel suddenly increases (the rate of pressure increase exceeds 5 kPa / min), it may indicate that the material has decomposed and produced gas or that the seal has failed. The system will immediately stop heating and increase the nitrogen injection rate, while simultaneously issuing an alarm.

[0053] The above four-level interlocking protection logic is independent of each other and does not interfere with each other. Triggering any level of interlocking will not affect the normal monitoring function of other interlocks, thus ensuring the inherent safety of equipment operation.

[0054] In addition, after each batch of drying operations is completed, the equipment of the present invention is cleaned and maintained according to the following procedure to ensure long-term stable operation of the equipment, as follows: Online cleaning procedure: After drying and unloading, inject an appropriate amount of cleaning solvent (20% to 30% of the effective volume) into the vessel. Start the stirring shaft 5 and run it at the highest speed for 15 to 30 minutes. The residual material is removed by the scraping action of the elastic scraper assembly 8 and the dissolving action of the solvent. During the cleaning process, the heating jacket 4 is maintained at 50 to 70°C to reduce the viscosity of the residual material. After cleaning, the cleaning liquid is discharged through the discharge system, and the residual solvent is evaporated by vacuum drying.

[0055] Inspection of the elastic scraper assembly 8: Inspect the wear of the scraper blade 83 every 500 hours of operation. Measure the actual contact pressure between the scraper blade 83 and the vessel wall (using pressure test paper) through the observation hole or by opening the manhole while the machine is stopped. Replace the disc spring assembly when the compression of the elastic clamping mechanism 82 exceeds 70% of the total stroke. Replace the scraper blade 83 when the wear exceeds 40% of its initial thickness.

[0056] Maintenance of magnetic coupling drive device 2: Check the magnetic force of the outer magnetic rotor 21 and inner magnetic rotor 22 every 2000 hours of operation, and measure the magnetic induction intensity on the magnet surface using a gaussmeter. If the magnetic induction intensity decreases by more than 5% of the initial value, consider replacing the magnet. Simultaneously check the wall thickness of the non-magnetic isolation cover 23 (using an ultrasonic thickness gauge); if the wall thickness decreases by more than 10% of the initial value, the isolation cover should be replaced. Clean the fan filter of the forced air-cooled cover 26 monthly.

[0057] Example 2: This embodiment provides an explosion-proof stirring vacuum drying autoclave, drying method, and packaging system for processing special rubber additives (modified silicone tackifiers). The material is a high-viscosity paste with an initial viscosity of approximately 50,000 mPa·s, which increases to approximately 120,000 mPa·s during the drying process. This material is characterized by extremely strong adhesion, exhibiting a much higher adhesion force to metal surfaces than ordinary materials.

[0058] Compared with Example 1, the main difference in this example is: Regarding the elastic scraper assembly 8, considering the high adhesion of the material, the disc spring combination of the elastic clamping mechanism 82 was changed to 4 discs connected in series, increasing the elastic clamping force to 120N and the compensation stroke to 6mm. The carbon fiber mass fraction of the scraper blade 83 was increased to 40% to enhance its wear resistance and rigidity, and the thickness of the scraper blade 83 was increased to 8mm. The number of elastic scraper assemblies 8 installed on the wall-scraping agitator frame 7 was increased to 16 sets, and the spacing between adjacent scrapers was shortened to 220mm to improve wall coverage.

[0059] Regarding the magnetic coupling drive device 2, due to the high viscosity of the material and the small size of the vessel body 3, the required stirring torque is approximately 1500 N·m. The outer magnetic rotor 21 and the inner magnetic rotor 22 have 6 pairs of magnetic poles and a rated transmission torque of 2000 N·m, which meets the usage requirements.

[0060] Regarding the intelligent control system, due to the narrow viscosity range of the material (50,000 to 120,000 mPa·s), the first set threshold was set to 70,000 mPa·s, and the second set threshold was set to 100,000 mPa·s. The empirical constant of the viscosity estimation algorithm was calibrated as follows: =72.3, =-0.98.

[0061] The drying process parameters in this embodiment are: heating temperature 80℃ at the top and 90℃ at the bottom, stirring speed 20 rpm, and vacuum degree 5 kPa. The drying time is approximately 6 hours, and the unloading residue rate is 0.8%. Using this system to process this material, the batch processing time is reduced by 35% compared to traditional rigid scraper equipment, and the heat transfer efficiency remains above 92% after 300 hours of operation.

[0062] Example 3: This embodiment provides an explosion-proof stirring vacuum drying kettle, drying method, and packaging system for anti-scaling high-viscosity materials, used to process polymer precursors (polyimide precursor solutions). The material has extremely high viscosity in the later stage of drying, reaching more than 300,000 mPa·s, and has obvious shear thinning characteristics, making it prone to "shaft binding".

[0063] Compared with Example 1, the main difference in this example is: Regarding the mixing components, the diameter of the mixing main shaft 5 is increased to 160mm, and the ribbon width of the internal ribbon agitator 6 is 150mm, with an outer diameter of 1100mm. Eighteen sets of elastic scraper assemblies 8 are installed on the wall-scraping mixing frame 7. An auxiliary scraper is added to the bottom anchor paddle 9, and elastic scraper assemblies 8 are also installed on the leading edge of the anchor paddle blades to prevent severe accumulation of high-viscosity materials at the bottom of the cone.

[0064] Regarding the magnetic coupling transmission device 2, to meet the stirring requirements of extremely high viscosity materials, the number of magnetic pole pairs of the outer magnetic rotor 21 and the inner magnetic rotor 22 is increased to 10 pairs, the thickness of the magnetic tiles is increased to 20mm, the rated transmission torque reaches 3500N·m, and the maximum transmission torque is 4500N·m. The airflow of the forced air-cooled shield 26 outside the outer magnetic rotor 21 is increased to 800m³. 3 / h, to cope with greater eddy current heating during high torque transmission. The non-magnetic isolation cover 23 is now made of Hastelloy C-276 material with a wall thickness of 5mm for better corrosion resistance.

[0065] Regarding the elastic scraper assembly 8, the disc spring combination of the elastic clamping mechanism 82 is changed to 5 discs connected in series, increasing the elastic clamping force to 150N and the compensation stroke to 7.5mm. The scraper blade 83 has a thickness of 6mm and a carbon fiber mass fraction of 35%.

[0066] Regarding the intelligent control system, the first set threshold is set to 100,000 mPa·s, and the second set threshold is set to 250,000 mPa·s. When the enhanced wall scraping program is triggered, the forward and reverse rotation cycle is shortened to 15 seconds forward rotation, 3 seconds stop, and 15 seconds reverse rotation, using higher frequency shear force to disrupt the polymer network structure and prevent shaft seizure. Furthermore, the intelligent control system includes a torque surge detection function: when the torque increases by more than 30% of the rated torque within 1 second, the system immediately executes an emergency reverse operation, continuing for 10 seconds before resuming normal stirring to prevent equipment damage caused by sudden material solidification. The empirical constant of the viscosity estimation algorithm has been calibrated to... =112.5, =-1.12.

[0067] The drying process parameters in this embodiment are: heating temperature 100℃ for the upper part and 120℃ for the lower part, initial stirring speed 15 rpm, and vacuum degree 3 kPa. The drying time is approximately 12 hours. Using this system to dry the polymer precursor, the batch processing time is reduced by 40% compared to traditional equipment, and the unloading residue rate is less than 1.0%, while the unloading residue rate of traditional equipment is usually as high as 5% to 8%.

[0068] Comparative Examples 1-2: To further verify the technical effects of the present invention, a systematic comparative experiment was conducted. Experimental conditions: The equipment from Example 1 was used as the test platform; the material was a dry nitrocellulose simulant (a mixture of glycerol and sodium carboxymethyl cellulose) with a viscosity of approximately 180,000 mPa·s; and the experiment was conducted continuously for 500 hours.

[0069] Comparative Example 1: The equipment uses a traditional vacuum drying kettle of the same specifications, equipped with a rigid scraper and a mechanical seal.

[0070] Comparative Example 2: Using the same equipment as the embodiment, but without enabling "viscosity adaptive control based on power coefficient", a fixed rotation speed and constant heating temperature were used throughout the process.

[0071] The test results are as follows: Comparative Example 1: After 50 hours of operation, the heat transfer efficiency of Comparative Example 1 decreased sharply by 30% due to the increased gap caused by scraper wear, and the wall surface scale thickness reached 3-5mm; while the embodiment of the present invention, due to the use of elastic clamping mechanism 82 and PEEK carbon fiber scraper, adaptively compensated for wear, and the heat transfer efficiency remained above 95%, with no obvious scale on the wall surface.

[0072] Comparative Example 2: As the viscosity of the material increased dramatically during drying, Comparative Example 2 frequently experienced motor overload alarms and localized overheating of the material, resulting in a batch drying time that was extended by approximately 30%. In contrast, the embodiment of the present invention uses real-time viscosity estimation to automatically reduce the speed of heating and intermittent forward and reverse rotation, resulting in stable operation without overload and a significant reduction in batch drying time.

[0073] As can be seen from Examples 1-3 and Comparative Examples 1-2, the present invention is significantly superior to the prior art in terms of anti-scaling, heat transfer efficiency, drying efficiency, unloading integrity, sealing safety and antistatic performance. Moreover, the improvement of each performance indicator is not a simple linear superposition, but reflects the synergistic effect between the elastic scraper, magnetic transmission, antistatic network and nitrogen protection.

[0074] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A scale-resistant, explosion-proof stirring vacuum drying kettle for high-viscosity materials, characterized in that, Includes vacuum drying kettle components, combined anti-scaling stirring components, system-level explosion-proof components, and intelligent control system: The vacuum drying vessel assembly includes a vessel body (3) with a heating jacket (4). The vessel body (3) includes an upper cylindrical section (31) and a lower conical section (32) connected in series. The upper cylindrical section (31) is provided with a feed inlet (33), a vacuum port (121), and a nitrogen inlet (122) at its upper part. The lower conical section (32) is provided with a discharge port at its lower part. The feed inlet (33) is used to add the material to be dried into the vessel body (3). The vacuum port (121) is connected to a vacuum device and is used to evacuate the vessel body (3). The discharge port is used to discharge the dried material. The heating jacket (4) is equipped with a heating source. The combined anti-scaling stirring assembly includes a stirring spindle (5), a stirring unit, a wall-scraping stirring frame (7), and a scraper unit. The stirring unit and the wall-scraping stirring frame (7) are rotatably mounted on the stirring spindle (5), and the stirring unit and the wall-scraping stirring frame (7) have opposite spiral directions to form a three-dimensional circulating flow field. The scraper unit is mounted on the wall-scraping stirring frame (7) to prevent scaling on the inner wall of the vessel body (3). The stirring unit includes an internal spiral ribbon stirrer (6) and a bottom anchor paddle (9). The internal spiral ribbon stirrer (6) is located in the upper cylindrical section (31), and the bottom anchor paddle (9) is located in the lower conical section (32). The system-level explosion-proof components include an explosion-proof drive motor (1), a magnetic coupling transmission device (2), an anti-static grounding system, and a nitrogen sealing protection system; the stirring spindle (5) is connected to the explosion-proof drive motor (1) through the magnetic coupling transmission device (2); the rated transmission torque of the magnetic coupling transmission device (2) is not less than 2000 N·m, and the number of magnetic pole pairs is not less than 6 pairs; The scraper unit includes multiple sets of elastic scraper assemblies (8) installed on the wall-scraping stirring frame (7); the elastic scraper assembly (8) includes a scraper seat (81), an elastic pressing mechanism (82) and a scraper blade (83). The scraper seat (81) is disposed on the wall-scraping stirring frame (7), and the scraper blade (83) is disposed on the scraper seat (81) through the elastic pressing mechanism (82). The elastic pressing mechanism (82) enables the scraper blade (83) to always be in close contact with the inner wall of the vessel body (3) under the action of elastic force, and adaptively compensates for the wear of the scraper blade (83) and the deformation of the vessel wall. The anti-static grounding system includes a conductive structural component installed in the scraper unit. The conductive structural component is electrically connected to the grounding copper busbar through the scraper stirring frame (7) and the stirring main shaft (5) to form a static discharge path. Specifically, the conductive structural component is integrated into the elastic scraper assembly (8). The inside of the scraper blade (83) is embedded with a conductive carbon fiber network (84). The conductive carbon fiber network (84) is electrically connected to the metal skeleton of the scraper stirring frame (7) through the metal contact surface of the scraper seat (81), and then conducted to the grounding carbon brush (25) at the top of the main shaft through the stirring main shaft (5). Finally, it is connected to the grounding copper busbar to form a complete static discharge path, realizing continuous static discharge of the rotating scraper component in the working state. The scraping and descaling and static discharge structure are integrated into one. The nitrogen sealing protection system includes a gas supply pipe, valves, and an oxygen content detector. The gas supply pipe connects the gas source and the nitrogen inlet (122). A valve is installed on the gas supply pipe. The oxygen content detector is used to detect the oxygen content of the vessel (3). Specifically, the oxygen content detector is connected to the controller. When the oxygen content in the system exceeds 3%, the system issues a first-level alarm and automatically increases the nitrogen injection flow rate to 3 times the normal value. When the oxygen content exceeds 5%, the system issues a second-level alarm, stops the stirring motor and heating system, and simultaneously opens the emergency nitrogen charging valve to inject nitrogen into the vessel at the maximum flow rate, thereby realizing closed-loop interlock control of the oxygen content in the vessel and maintaining the oxygen content in the vessel within the safe threshold. The intelligent control system includes a controller and a torque sensor. The torque sensor is installed on the stirring spindle (5) to obtain the rotational speed and torque signal of the stirring spindle (5). The torque sensor, oxygen content detector, heating source, vacuum pump, explosion-proof drive motor (1), and valves are all connected to the input end of the controller. The output end of the controller is connected to the explosion-proof drive motor (1), heating execution unit, vacuum pump, and electromagnetic gas injection valve group. During joint operation, the controller performs vacuuming-nitrogen replacement based on oxygen content and vacuum degree feedback and confirms safety conditions. It adjusts the heating zone temperature and stirring speed according to temperature, pressure, and torque feedback closed loop to realize the adaptive control of stirring speed, heating power, vacuum pumping, and nitrogen supply.

2. The anti-scaling, explosion-proof stirring vacuum drying kettle for high-viscosity materials according to claim 1, characterized in that, The controller includes an input module, a processing module, and an output module; Both the torque sensor and the oxygen content detector are connected to the input module; The heating source, vacuum device, explosion-proof drive motor (1), and valve are all connected to the output module; The processing module has a built-in viscosity estimation algorithm. It calculates the viscosity of the material based on the stirring speed and torque signals obtained by the input module and makes a judgment. Specifically, when the viscosity of the material exceeds the first set threshold, the output module controls the explosion-proof drive motor (1) to reduce the stirring speed and controls the heating source to increase the temperature of the heating jacket (4). When the viscosity of the material exceeds the second set threshold, the output module controls the explosion-proof drive motor (1) to realize the intermittent forward and reverse operation of the stirring spindle.

3. The anti-scaling, explosion-proof stirring vacuum drying kettle for high-viscosity materials according to claim 2, characterized in that, The processing module also has a built-in correlation formula for stirring power, as follows: ； in: For power parameters, , This refers to the actual stirring power. =2π , This refers to the stirring speed. The stirring torque is collected by a torque sensor. For material density, The diameter of the vessel body (3); It is the Reynolds number; and These are pre-calibrated empirical constants; Viscosity of the material Calculate using the following formula: ； The first set threshold is 50,000 to 150,000 mPa·s, and the second set threshold is 150,000 to 300,000 mPa·s; the empirical constant in the power metric correlation. The value range is from 50 to 200, an empirical constant. The value range is -1.2 to -0.

8. This empirical constant was obtained through calibration experiments using standard silicone oil of known viscosity within a speed range of 5 rpm to 60 rpm. Specifically, under no-load and load conditions, multi-condition tests were conducted within the 5 rpm to 60 rpm speed range, and the result was obtained through a double logarithmic coordinate least squares regression fitting calibration. The goodness of fit R0 was... 2 With a viscosity not lower than 0.99, it is compatible with the flow field characteristics of conical kettles with reverse spiral combined stirring configuration, enabling the estimation of material viscosity without an external online viscometer under high temperature and high vacuum conditions.

4. The anti-scaling, explosion-proof stirring vacuum drying kettle for high-viscosity materials according to claim 1, characterized in that, The inner spiral agitator (6) is provided with a wall-scraping agitator frame (7) on the outside. The spiral directions of the inner spiral agitator (6) and the wall-scraping agitator frame (7) are opposite, forming a three-dimensional circulating flow field.

5. The anti-scaling, explosion-proof stirring vacuum drying kettle for high-viscosity materials according to claim 1, characterized in that, The magnetic coupling transmission device (2) includes an outer magnetic rotor (21), an inner magnetic rotor (22), and a non-magnetic isolation cover (23) that is sealed to the top flange of the vessel body (3) to achieve a completely static sealed transmission of the stirring shaft (5); both the outer magnetic rotor (21) and the inner magnetic rotor (22) are neodymium iron boron rare earth permanent magnets; the non-magnetic isolation cover (23) is a cylinder made of titanium alloy or Hastelloy alloy with a wall thickness of 3 to 6 mm; the outer magnetic rotor (21) is provided with a forced air cooling cover (26) to dissipate the heat generated by the eddy current.

6. A method for drying materials, characterized in that, Drying is performed using the anti-scaling, explosion-proof, stirred vacuum drying kettle for high-viscosity materials as described in claim 3, comprising the following steps: Step 1, Feeding and Atmosphere Replacement: The material enters the interior of the vessel (3) through the feed port (33). The nitrogen sealing protection system is started to perform at least three vacuuming-nitrogen filling cycles on the vessel (3). Each time, after vacuuming to an absolute pressure of no more than 5 kPa, nitrogen is filled to a slightly positive pressure so that the oxygen content inside the vessel (3) drops to below 2%. Step 2, heating and stirring drying: turn on the heating source to heat the heating jacket (4), set the temperature of the upper cylindrical section (31) to 60°C to 120°C and the temperature of the lower conical section (32) to 80°C to 150°C, and start the stirring spindle (5) at a speed of 5 rpm to 60 rpm, and turn on the vacuum system to maintain the absolute pressure inside the vessel in the range of 1 kPa to 20 kPa; Step 3, Intelligent Adaptive Control: The intelligent control system collects the stirring torque in real time through the torque sensor and calculates the viscosity of the material based on the power coefficient correlation formula; when the viscosity of the material exceeds the first set threshold, it automatically reduces the stirring speed by 20% to 50% and increases the temperature of the lower cone section (32) by 5°C to 15°C; when the viscosity of the material exceeds the second set threshold, it controls the stirring spindle (5) to perform intermittent forward and reverse rotation operations according to the cycle of forward rotation for 20 to 30 seconds, stop for 3 to 5 seconds, and reverse rotation for 20 to 30 seconds. Step 4: The dried material is output through the discharge port.

7. A packaging system, characterized in that, The container comprises, as described in any one of claims 1 to 5, an explosion-proof stirring vacuum drying vessel for anti-scaling high-viscosity materials, and further comprises: The sealed transition and conveying assembly, connected to the outlet of the vessel body (3), includes, in sequence, a discharge ball valve (10), a star-shaped discharge valve (11), a vacuum transition chamber (12), and a shaftless screw conveyor (13); the gap between the rotor blades of the star-shaped discharge valve (11) and the shell is no more than 0.1 mm; the vacuum transition chamber (12) is provided with an independent vacuum port (121) and a nitrogen inlet (122), the vacuum port (121) is connected to a vacuum device; the nitrogen inlet (122) is connected to a nitrogen source through a pipeline; The automatic packaging assembly (14), connected to the outlet of the shaftless screw conveyor (13), includes a buffer hopper (141), a metering and weighing unit (142), an automatic bag making and filling machine (143), and a nitrogen-filling heat sealing unit (144).

8. The packaging system according to claim 7, characterized in that, The star-shaped discharge valve (11) is equipped with a steam heat tracing jacket (111) to maintain the valve body temperature within the range of 40°C to 80°C to prevent material solidification; the shaftless screw conveyor (13) is equipped with a heat tracing and insulation sleeve (133) to maintain the conveying temperature within the range of 50°C to 90°C.

9. A packaging method, characterized in that, Packaging is achieved based on the packaging system described in claim 7 or 8, specifically including: opening the discharge ball valve (10) and the star-shaped discharge valve (11) in sequence, the material output through the discharge port enters the shaftless screw conveyor (13) through the vacuum transition chamber (12), is conveyed to the buffer hopper (141) of the automatic packaging component (14), is weighed by the metering and weighing unit (142), and is filled by the automatic bag making and filling machine (143), and finally is heat-sealed by the nitrogen filling heat sealing unit (144) under nitrogen protection.

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