Automatic synthesis and separation control system for fluoroethylene carbonate

Abstract

The invention relates to an automatic synthesis and separation control system for fluoroethylene carbonate, and relates to the technical field of chemical synthesis and separation. Comprising a feeding unit, a dissolving unit, a synthesis unit, a separation unit, a drying and conveying unit and a nitrogen balance system, each unit is provided with various devices and assemblies to complete corresponding functions, for example, the feeding unit realizes automatic feeding of potassium fluoride, and the synthesis unit performs synthesis of fluoroethylene carbonate. And the system realizes full-process automatic operation through a DCS (Distributed Control System) automatic control program. The device achieves the technical effects of realizing full-process automatic operation of automatic synthesis and separation of fluoroethylene carbonate, effectively controlling operation of equipment according to data of various instruments in an interlocking manner, and improving the production efficiency and quality.

Description

Technical Field

[0001] The present application relates to the field of chemical synthesis and separation technology, and in particular to an automatic synthesis and separation control system for fluoroethylene carbonate. Background Art

[0002] Fluoroethylene carbonate (FEC) is a core additive specifically developed for electrolytes used in high-rate power lithium-ion batteries. It is the primary guarantee for achieving high safety and high-rate lithium batteries, and can enhance the stability of electrode materials. Electrolytes with the addition of FEC can form an effective SEI film on the surface of battery electrodes, increasing the battery's lithium ion migration rate and significantly improving the battery's charge and discharge performance at high rates. At the same time, FEC is beneficial for silicon-carbon negative electrodes because the SEI film it forms is thin, tough, and self-healing. This can inhibit the structural breakage of the silicon-carbon negative electrode caused by volume expansion due to lithium embedding during charge and discharge, significantly extending the service life of the silicon-carbon negative electrode and promoting its widespread application. Currently, lithium batteries with the addition of FEC are mainly suitable for hybrid and pure electric vehicles, and are expected to be used in energy storage in solar and wind energy fields in the future, with broad market prospects.

[0003] In the field of fluoroethylene carbonate synthesis, potassium fluoride feeding is currently primarily accomplished by manually placing ton bags of potassium fluoride into a workshop feed bin. Following fluoroethylene carbonate synthesis, the product is typically separated using conventional filtering and washing equipment. Conventional drying equipment is used to dry the potassium chloride salt, and either open or sealed conveying devices are employed for transport. These are common methods used to address similar issues in the past.

[0004] However, existing technologies have significant drawbacks. Manually adding potassium fluoride to the synthesis reactor results in high dust levels in the workshop and poses safety risks. Furthermore, the fluorination process itself is prone to accidents due to runaway reactions. The order, amount, and rate of addition of upstream materials significantly influence the reaction rate, making it easy for human error to cause runaway reactions. Furthermore, the process's reaction products pose significant safety risks, and subsequent separation operations downstream are also highly dangerous. Given the dense on-site workforce, an accident could easily lead to mass casualties. Summary of the Invention

[0005] In order to solve the above problems, the present application provides a system for automatically synthesizing and separating fluoroethylene carbonate.

[0006] A fluoroethylene carbonate automatic synthesis and separation control system, comprising: The feeding unit is used to realize automatic feeding of potassium fluoride, including a ton bag hoisting frame, an electric hoist, a ton bag feeding box, a bag breaking mechanism and a potassium fluoride silo. The ton bag hoisting frame is connected to the electric hoist. The ton bag feeding box is provided with a bag breaking mechanism, which is provided with a blade. The potassium fluoride silo is provided below the ton bag feeding box and is provided with a weighing module. A dissolving unit, used for dissolving potassium fluoride, comprises a potassium fluoride dissolving kettle, a stirring device, a feeding pipeline and temperature and pressure measuring instruments. The stirring device comprises a stirring motor and an ammeter, and the feeding pipeline is provided with a flow meter and a shut-off valve; A synthesis unit for the synthesis of fluoroethylene carbonate, comprising an FEC synthesis reactor, a stirring paddle assembly, a heating and cooling system, and feed and discharge pipelines. The stirring paddle assembly is a combination of a downward pressure two-blade CBY paddle and a three-blade swept paddle. The heating system includes a steam pipeline, and the cooling system includes a circulating water line. A separation unit for separating the synthetic product, comprising an FEC temporary storage kettle, a hose pump, an accumulator, and a rotary filter press. The FEC temporary storage kettle is provided with a stirring paddle. The hose pump outlet is connected to the accumulator. The rotary filter press comprises a filtration zone, at least three washing zones, and a drying zone. The drying and conveying unit is used for drying and conveying potassium chloride salt, and includes a paddle dryer, a gas condenser, a temporary storage tank and a scraper conveyor. The inlet pipeline of the paddle dryer is provided with a sight glass, the gas condenser is provided with a circulating water system and a flushing pipeline, and the scraper conveyor adopts a closed micro-negative pressure conveying method.

[0007] By adopting the above technical solution, the entire process starting from the addition of potassium fluoride is automatically controlled, meeting the national requirements for automated control of hazardous chemical processes and reducing dust and safety hazards in the workshop; the agitator combination is conducive to crystal growth, making the crystal particle size distribution uniform and the materials quickly mixed, which is beneficial to the reaction crystallization process; the rotary drum filter press has high separation efficiency and a high degree of automation, and does not require human intervention; the hose pump and accumulator ensure the stability of the feed pressure and flow of the rotary drum filter press; the closed micro-negative pressure conveying of the scraper conveyor can prevent the volatilization of residual organic matter on the surface of the potassium salt into the atmosphere; the flushing function of the gas condenser and the self-cleaning filter ensure the continuous and stable operation of the paddle dryer.

[0008] Preferably, in the feeding unit, a dust exhaust port is provided on the side of the ton bag feeding box, the dust exhaust port is connected to a dust collector, a cloth bag and a nitrogen backflush device are provided in the dust collector, a cut-off valve and a pneumatic vibrator are provided at the potassium fluoride discharge port in the ton bag feeding box, and a sight glass is provided below the discharge port.

[0009] By adopting the above technical solution, the dust exhaust port and dust collector can be combined to reduce dust in the workshop, the bag filter and nitrogen backflush device can ensure the dust removal effect, the shut-off valve can control the discharge, the pneumatic vibrator can prevent potassium fluoride from accumulating at the bottom of the silo, and the sight glass can facilitate the inspection of the discharge status, thus realizing automatic feeding of potassium fluoride and ensuring the environmental protection, safety and controllability of the feeding process.

[0010] Preferably, in the synthesis unit, the FEC synthesis kettle is provided with a condenser, which includes a circulating water supply and return pipeline, a venting pipeline and a temperature measuring point. A shut-off valve is provided at the bottom of the venting pipeline to form a liquid seal to prevent direct venting of DMC after vaporization.

[0011] By adopting the above technical solution, the vaporized DMC is condensed and liquefied by the circulating water supply return line of the condenser and returned to the FEC synthesis reactor. At the same time, the shut-off valve at the bottom of the venting line can form a liquid seal to prevent the DMC from being directly vented without condensation and liquefaction after vaporization, thereby ensuring the full utilization of the material and the stability of the reaction.

[0012] Preferably, in the separation unit, the washing area of ​​the rotary drum filter press includes a primary washing area, a secondary washing area and a tertiary washing area, the primary washing area is connected to the secondary washing liquid tank, the secondary washing area is connected to the tertiary washing liquid tank, and the tertiary washing area is connected to the filter cloth flushing liquid tank, and each washing area is provided with a delivery pump, a pressure regulating valve and a pressure measuring point.

[0013] By adopting the above technical solution, the separated product of the rotary drum filter press is washed three times, and the washing process is controlled by a delivery pump, a pressure regulating valve and a pressure measuring point. This can more fully clean the product, reduce residual impurities, further improve the separation effect, and ensure product quality. In addition, this process has a high degree of automation and does not require human intervention.

[0014] Preferably, in the drying and conveying unit, the gas condenser outlet is connected to a temporary storage tank, the temporary storage tank is provided with a liquid level gauge and a conveying pump, the conveying pump outlet is connected to a self-cleaning filter, and the scraper conveyor adopts a multiple-unit relay conveying method. The entire conveying process is a system-enclosed micro-negative pressure operation.

[0015] By adopting the above technical solution, the outlet of the gas condenser is connected to a temporary storage tank and equipped with a liquid level gauge and a delivery pump, which can monitor the liquid level and deliver materials in time; the outlet of the delivery pump is connected to a self-cleaning filter, which can filter the conveyed material to prevent impurities from entering the subsequent system; the scraper conveyor adopts a multiple-unit relay conveying method and transports potassium chloride salt under the closed system micro-negative pressure operation, which can prevent the organic matter remaining on the surface of the potassium salt from volatilizing into the atmosphere, ensuring environmental safety and efficient completion of material transportation.

[0016] Preferably, the system further comprises a nitrogen balancing system, which comprises a plurality of nitrogen pipelines, respectively used to balance the pressure of the mother liquid tank, the washing liquid tank and the equipment, and the nitrogen pipelines are provided with self-operated regulating valves and pressure measuring points.

[0017] By adopting the above technical solution, a nitrogen balance system is set up, and multiple nitrogen pipelines are used to balance the pressure of the mother liquor tank, washing liquid tank and equipment respectively. In conjunction with the self-operated regulating valves and pressure measuring points on the nitrogen pipelines, the pressure of each container and equipment in the system can be ensured to be stable, thereby ensuring the safe and stable operation of the entire fluoroethylene carbonate automatic synthesis and separation control system.

[0018] Preferably, the potassium fluoride dissolution kettle and the FEC synthesis kettle are both provided with weighing modules, which are used to control the feed amount in a chain manner. The FEC synthesis kettle is also provided with a pressure measuring point and a temperature gauge for monitoring the pressure and temperature during the reaction process.

[0019] By adopting the above technical solution, the weighing module is used to control the feed amount of the potassium fluoride dissolution kettle and the FEC synthesis kettle in a chain manner, which can ensure the accuracy and stability of the feed amount of each batch and meet the stable control of process production; the pressure measuring point and temperature gauge equipped with the FEC synthesis kettle can monitor the pressure and temperature of the reaction process, which helps to timely understand the reaction status and ensure production safety and product quality.

[0020] Preferably, the drying area of ​​the rotary drum filter press uses a nitrogen pipeline for pre-drying, and the nitrogen pipeline is provided with a flow meter, a pressure regulating valve and a pressure measuring point. The gas-liquid mixture generated by pre-drying enters a drying gas-liquid tank, and the drying gas-liquid tank is provided with a liquid level meter, a delivery pump and a venting pipeline.

[0021] By adopting the above technical solution, a nitrogen pipeline with a flow meter, a pressure regulating valve and a pressure measuring point is used for pre-drying in the drying area of ​​the rotary drum filter press, which can effectively control the drying process and ensure the drying effect; the gas-liquid mixture produced by pre-drying enters a drying gas-liquid tank equipped with a liquid level meter, a delivery pump and a venting pipeline, which can effectively process the gas-liquid mixture. The liquid level meter can monitor the liquid level in the tank, the delivery pump facilitates material transportation, and the venting pipeline can discharge the gas during the drying process, thereby ensuring that the entire separation and drying process is more stable and efficient.

[0022] Preferably, the paddle dryer is provided with a steam pipeline and a circulating water supply and return pipeline, the steam pipeline is provided with a flow meter, a regulating valve, a pressure measuring point and a temperature measuring point, and the paddle dryer body is provided with a temperature measuring point for controlling the drying temperature according to the residual DMC content of potassium chloride salt.

[0023] By adopting the above technical solution, the paddle dryer is equipped with a steam pipeline and a circulating water supply and return pipeline, which can realize the heating and cooling of potassium chloride salt; the flow meter, regulating valve, pressure measuring point and temperature measuring point installed on the steam pipeline can accurately control the steam flow, adjust the valve, and monitor the pressure and temperature; the temperature measuring point on the paddle dryer body can control the drying temperature according to the residual DMC content of potassium chloride salt, ensuring the drying effect and adapting to different residual conditions, thereby ensuring stable operation of the equipment and effectively removing DMC from potassium chloride salt.

[0024] Preferably, the system realizes full-process automated operation through a DCS automatic control program, including the lifting, bag breaking, and unloading of potassium fluoride ton bags, and the dissolution, synthesis, separation, drying, and transportation of the materials. The DCS automatic control program can interlock and control the operation of each device based on the data of instruments such as weighing modules, flow meters, thermometers, and pressure gauges.

[0025] By adopting the above technical solution, the entire process of fluoroethylene carbonate synthesis and separation is automated, meeting the national requirements for automated control of hazardous chemical process production equipment, reducing workshop dust and safety hazards, and avoiding uncontrolled reactions caused by human operational errors. The system interlocks and controls equipment operation based on instrument data, ensuring stable control of process production, improving the accuracy of synthesis and the efficiency of crude separation, and reducing the number of people in the workplace. The separation of the mother liquor and potassium chloride after synthesis does not require human intervention, and the equipment has a high degree of automation. It also prevents residual organic matter on the surface of the potassium salt from volatilizing into the atmosphere.

[0026] In summary, this application includes at least one of the following beneficial technical effects: 1. The synthesis and crude separation of fluoroethylene carbonate can be realized without manual operation and automatically controlled by the system, meeting national safety requirements and ensuring stable control of process production; 2. The feeding unit and the dissolving unit cooperate to avoid the problems of large dust in the workshop and safety hazards caused by manual feeding. Each unit accurately controls the amount, rate and sequence of material addition to avoid the reaction out of control due to human operation errors. 3. The synthesis unit adopts a combination of a downward pressure two-blade CBY impeller and a three-blade swept impeller to make the crystal particle size distribution uniform and larger, which is conducive to the subsequent separation of the drum filter press. The separation unit uses the drum filter press to achieve efficient separation, and the drying and conveying unit adopts a closed micro-negative pressure to convey potassium chloride salt to prevent organic matter from volatilizing into the workshop or the atmosphere. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural diagram of the feeding unit; Figure 2 It is a schematic diagram of the combined structure of the feeding unit and the dissolving unit; Figure 3It is a schematic diagram of the combined structure of the synthesis unit and the separation unit; Figure 4 and Figure 5 It is a process flow chart of an embodiment of the present application. Explanation of reference numerals: 1. Ton bag lifting frame; 2. Hoist hook lock; 3. Electric hoist; 4. Ton bag feeding box door; 5. Guide rail; 6. Ton bag feeding box; 7. Bag breaking mechanism; 8. Blade; 9. Weighing module; 10. Dust outlet; 11. Dust collector; 12. Cloth bag; 13. Discharge port; 14. Nitrogen backflush device; 15. Feeding port; 16. Discharge port; 17. Shut-off valve; 19. Discharge port; 20. Pneumatic vibrator; 21. Feeding valve; 22. Sight glass Mirror; 23. DMC solvent delivery pipeline; 24. Feed flowmeter; 25. Feed shut-off valve; 26. Potassium fluoride dissolving kettle; 27. Stirring device; 28. Ammeter; 30. Delivery pipeline; 31. Pressure gauge; 32. Thermometer; 34. Current display; 37. CEC dripping tank; 38. Liquid level gauge; 39. Stirring paddle motor; 40. Feed flowmeter; 41. Feed regulating valve; 42. Condenser; 43. Circulating water supply pipeline; 44. Return pipeline; 46. ​​Vent line; 48. Temperature measuring point; 50. Pressure measuring point; 51. Thermometer; 52. Feed valve; 53. Steam line; 55. Return line; 56. Condensate line; 59. Cooling circulating water line; 61. FEC temporary storage kettle; 62. Stirring motor; 63. Hose pump; 64. Accumulator; 67. Stirring paddle; 69. FEC synthesis kettle; 70. Temperature measuring point; 73. Nitrogen line; 83. Self-operated regulating valve; 87. Pressure regulating valve; 88 , flow meter; 91, rotary drum filter press; 92, transfer pump; 96, tertiary washing liquid tank; 100, secondary washing liquid tank; 102, liquid level control valve; 104, mother liquor tank; 107, filter cloth washing liquid tank; 111, drying gas and liquid tank; 118, pipeline; 119, paddle dryer; 125, circulating water supply and return line; 136, liquid level regulating valve; 140, temporary storage tank; 143, self-cleaning filter; 144, gas condenser; 146, scraper conveyor. DETAILED DESCRIPTION

[0028] The present application is further described in detail below with reference to the accompanying drawings.

[0029] In the description of the invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the invention.

[0030] The embodiment of the present application discloses an automatic synthesis and separation control system for fluoroethylene carbonate, comprising a feeding unit, a dissolving unit, a synthesis unit, a separation unit, and a drying and conveying unit. The feeding unit realizes the automatic feeding of potassium fluoride, the dissolving unit dissolves potassium fluoride, the synthesis unit synthesizes fluoroethylene carbonate, the separation unit separates the synthesis product, and the drying and conveying unit dries and conveys potassium chloride salt. These units cooperate with each other to realize the manual operation-free synthesis and rough separation of fluoroethylene carbonate, and the automatic control of the system, while increasing the accuracy of the synthesis and the efficiency of the rough separation.

[0031] The feeding unit includes a ton bag hoisting frame 1, an electric hoist 3, a ton bag feeding box 6, a bag breaking mechanism 7, and a potassium fluoride silo. The electric hoist 3 moves along the guide rail 5 and can lift and lower the ton bag of potassium fluoride. The ton bag feeding box 6 is a box structure made of welded steel plates, and a bag breaking mechanism 7 is installed inside. The blade 8 on the bag breaking mechanism 7 can easily cut through the ton bag. The potassium fluoride silo is set below the ton bag feeding box 6 and is equipped with a weighing module 9, which can accurately measure the amount of material discharged. When the electric hoist 3 lifts the ton bag to the top of the bag breaking mechanism 7 and descends, the ton bag contacts the blade 8 and is cut, and the potassium fluoride falls into the potassium fluoride silo. If the single discharge amount is less than the set value, the electric hoist 3 is controlled to collide with the bag breaking mechanism 7 back and forth to put the residual potassium fluoride in the ton bag into the potassium fluoride silo. In the feeding unit, a dust outlet 10 is provided on the side of the ton bag feeding box 6. The dust outlet 10 is connected to a dust collector 11. A cloth bag 12 and a nitrogen backflush device 14 are provided in the dust collector 11. The nitrogen backflush device 14 periodically introduces nitrogen into the cloth bag 12 to cause the dust on the cloth bag 12 to fall. The potassium fluoride discharge port 15 in the ton bag feeding box 6 is provided with a shut-off valve 17 and a pneumatic vibrator 20, which can accurately control the discharge. When the discharge valve 21 is opened, the pneumatic vibrator 20 starts working to prevent potassium fluoride from accumulating at the bottom of the silo, resulting in the material not being able to be discharged. A sight glass 22 is provided below the discharge port 15 to facilitate the inspection of the discharge situation. The arrangement of the dust outlet 10 and the dust collector 11 effectively collects the dust generated during the bag breaking process and prevents the dust from being blown out. The use of the pneumatic vibrator 20 solves the problem of potassium fluoride accumulating at the bottom of the silo and ensures the smooth discharge of the material. The setting of the sight glass 22 makes it convenient for the operator to understand the material discharging situation in time so as to take corresponding measures.

[0032] The dissolution unit includes a potassium fluoride dissolution kettle 26, a stirring device 27, a feed pipeline, and temperature and pressure measuring instruments. The potassium fluoride dissolution kettle 26 is used to accommodate potassium fluoride and a solvent. The stirring device 27 includes a stirring motor 62 and an ammeter 28. The ammeter 28 is used to monitor the current of the stirring motor 62 to determine whether the stirring is normal. The feed pipeline is provided with a flow meter 88 and a shut-off valve 17. The flow meter 88 can monitor the feed amount in real time. The shut-off valve 17 can automatically close according to the set feed amount to control the feed. The solvent enters the potassium fluoride dissolution kettle 26 through the feed pipeline. The stirring motor 62 drives the stirring paddle 67 to stir the potassium fluoride and the solvent to fully dissolve them.

[0033] The synthesis unit includes an FEC synthesis reactor 69, an agitator 67 assembly, a heating and cooling system, and feed and discharge pipelines. The FEC synthesis reactor 69 can accommodate the reaction materials. The agitator 67 is a combination of a two-blade CBY impeller with downward pressure and a three-blade swept impeller. This combination allows for rapid mixing of the materials, which is highly beneficial for the reaction and crystallization process. The CBY impeller generates an axial flow pattern, resulting in low pressure head and weak shear, which prevents excessive contact nucleation and promotes crystal growth. The three-blade swept impeller is a radial flow impeller with upward-curved blades, allowing liquid to be discharged along the blades, providing excellent circulation. The heating system includes a steam line 53, which uses steam to heat the materials in the reactor until the initial reaction temperature is reached, at which point the steam is shut off and insulation begins. The cooling system includes a circulating water line. Based on the reading of the thermometer 51 on the reactor, the shut-off valve 17 on the circulating water line is interlocked and controlled, automatically opening when the temperature is high and closing when it is low, thereby controlling the reaction temperature. The reactants enter the FEC synthesis reactor 69 through the feed line for reaction, and the reacted materials are discharged through the discharge line. In the synthesis unit, the FEC synthesis reactor 69 is equipped with a condenser 42, which includes a circulating water supply and return line 125, a vent line 46, and a temperature measurement point 48. The condenser 42 exchanges heat with the vaporized DMC within the reactor, condensing and liquefying it. The circulating water supply and return line 125 is connected to a circulating water pump and a cooling tower, respectively, to provide circulating water to the condenser 42. A shut-off valve 17 is located at the bottom of the vent line 46. This valve closes during the initial stages of the feed cycle and opens when sufficient condensate accumulates in the line, forming a liquid seal to prevent the vaporized DMC from being discharged directly from the bottom of the condenser 42 without being condensed and liquefied. The temperature measurement point 48 is used to monitor the post-cooling temperature to adjust the circulating water flow rate in a timely manner. The configuration of the condenser 42 allows the vaporized DMC to be condensed and liquefied before returning to the FEC synthesis reactor 69, improving raw material utilization and reducing waste. The liquid seal formed by the shut-off valve 17 effectively prevents direct discharge of DMC, ensuring reaction stability and safety. The setting of the temperature measuring point 48 facilitates monitoring and adjustment of the working state of the condenser 42 .

[0034] The separation unit includes an FEC holding tank 61, a hose pump 63, an accumulator 64, and a rotary drum filter press 91. The FEC holding tank 61 is typically a horizontal or vertical tank with an internal agitator 67 to prevent sedimentation. A stirring motor 62 drives the agitator 67 to continuously operate, maintaining a uniform material state. The outlet of the hose pump 63 is connected to the accumulator 64, which stores energy and provides continuous and stable material pressure and flow. The rotary drum filter press 91 comprises a filtration zone, at least three washing zones, and a drying zone. The filtration zone filters the synthetic product, separating the mother liquor from the filter cake. The washing zones include primary, secondary, and tertiary washing zones. The primary washing zone is connected to a secondary washing liquid tank 100, the secondary washing zone is connected to a tertiary washing liquid tank 96, and the tertiary washing zone is connected to a filter cloth rinse tank 107. Each washing zone is equipped with a delivery pump 92, a pressure regulating valve 87, and a pressure measuring point 50. These devices control the delivery and pressure of the washing liquid, allowing the filter cake to be washed multiple times. The drying zone pre-dries the washed filter cake. In the separation unit, the drying zone of the rotary drum filter press 91 uses a nitrogen pipeline 73 for pre-drying. Nitrogen pipeline 73 is equipped with a flowmeter 88, a pressure regulating valve 87, and a pressure measuring point 50. Nitrogen pipeline 73 is connected to the workshop's nitrogen supply system. Flowmeter 88 monitors the nitrogen flow in real time, pressure regulating valve 87 adjusts the nitrogen pressure as needed, and pressure measuring point 50 monitors the pressure within nitrogen pipeline 73. The gas-liquid mixture produced during pre-drying enters the drying gas-liquid tank 111, which is equipped with a liquid level gauge 38, a transfer pump 92, and a vent line 46. The liquid level gauge 38 monitors the liquid level in the tank in real time. When the liquid level is high, the material is transferred to the filter cloth rinse liquid tank 107 via the transfer pump 92. The vent line 46 is used to discharge gases during the drying process. It is equipped with a pressure gauge 31 and a regulating valve to control the discharge pressure. Using nitrogen to pre-dry the filter cake accelerates drying and improves drying efficiency. The flowmeter 88, pressure regulating valve 87, and pressure measuring point 50 on nitrogen line 73 enable precise control of nitrogen flow and pressure, ensuring pre-drying quality. The presence of a drying gas-liquid tank 111 separates and processes the gas-liquid mixture produced during pre-drying, preventing environmental pollution and allowing for partial material recovery.

[0035] The drying and conveying unit includes a paddle dryer 119, a gas condenser 144, a temporary storage tank 140, and a scraper conveyor 146. The inlet pipeline of the paddle dryer 119 is equipped with a sight glass 22 made of transparent tempered glass, which facilitates observation of material discharge. The paddle dryer 119 is equipped with a steam line 53 and a circulating water supply and return line 125. The steam line 53 is equipped with a flow meter 88, a regulating valve, a pressure measuring point 50, and a temperature measuring point 70. Steam condensate is discharged from the line. The paddle dryer 119 body is equipped with a temperature measuring point 70 to control the drying temperature based on the residual DMC content in the potassium chloride salt. The residual DMC in the potassium chloride salt is heated and vaporized before entering the gas condenser 144, which is equipped with a circulating water system and a flushing line. The gaseous DMC is liquefied in the condenser 42 and enters the temporary storage tank 140. The exhaust gas enters the exhaust system through the pipeline. Temporary storage tank 140 is equipped with a liquid level gauge 38. When the liquid level is high, it is transported to the DMC storage tank in the workshop via a transfer pump 92, a self-cleaning filter 143, a liquid level regulating valve 136, and a pipeline. Scraper conveyors 146 utilize a multiple-unit relay system for conveying liquids. The entire conveying process operates under a closed, slightly negative pressure system, preventing organic matter remaining on the surface of the potassium salt from escaping into the atmosphere.

[0036] The system also includes a nitrogen balance system, which includes multiple nitrogen pipelines 73, which are used to balance the pressure of the mother liquid tank 104, the washing liquid tank and the equipment. The nitrogen pipeline 73 also uses a seamless steel pipe, and the pipeline is provided with a self-operated regulating valve 83 and a pressure measuring point 50. The self-operated regulating valve 83 can automatically adjust the flow of nitrogen according to the pressure in the equipment, and the pressure measuring point 50 is used to monitor the pressure in real time. Through the nitrogen balance system, the mother liquid is kept stable and the impact of pressure fluctuations on the equipment and process is avoided. The setting of the nitrogen balance system ensures the stability of the pressure in each tank and equipment, so that the material can flow and be transported smoothly. The automatic adjustment function of the self-operated regulating valve 83 improves the automation and stability of the system, reduces manual intervention, and reduces operational risks.

[0037] The working principle of this embodiment is as follows: a ton bag of potassium fluoride is manually placed in the lifting position of the workshop feed bin. The ton bag lifting frame 1 clamps the ton bag and connects to the hoist hook lock 2. The DCS operator activates the automatic control program, and the electric hoist 3 lifts the ton bag. After the lifting limit is triggered, the door 4 of the ton bag feed bin opens. The electric hoist 3 enters the bin along the guide rail 5, and the door automatically closes. The electric hoist 3 lowers the ton bag into contact with the bag breaking mechanism 7, and the blade 8 cuts through the ton bag. When the lowering limit is reached, the four-way blades 8 of the bag breaking mechanism 7 push open the bottom of the ton bag, and the potassium fluoride falls into the feed bin. The weighing module 9 monitors the discharge level. If it is insufficient, the electric hoist 3 collides with the bag breaking mechanism 7 to replenish the remaining ton bags. During the feeding process, dust enters the dust collector 11 through the dust outlet 10 of the ton bag feed bin 6. The dust is filtered by the bag 12 and discharged as exhaust gas. The nitrogen backflush device 14 clears the dust from the bag 12 and returns it to the feed bin.

[0038] Potassium fluoride from the bulk bag feed box 6 enters the silo through the discharge port 16. Dust is filtered through the bag 12 during discharge, and the shut-off valve 17 is closed upon completion. A pneumatic vibrator 20 at the bottom of the silo operates when the discharge valve 21 is open to prevent material accumulation. A sight glass 22 monitors the discharge progress. DMC is quantitatively delivered to the potassium fluoride dissolution vessel 26 via a delivery pipeline 30, a flowmeter 88, and a shut-off valve 17. Agitation is initiated, and an ammeter 28 monitors the agitation status. Potassium fluoride is fed into the dissolution vessel through the feed shut-off valve 25 according to the amount set by the weighing module 9. The pressure and temperature within the vessel are monitored during feeding. After dissolution, the material is delivered to the FEC synthesis vessel via the bottom shut-off valve 17, the delivery pipeline 30, and the shut-off valve 17. The dissolution vessel weighing module 9 controls the feed rate.

[0039] Start the synthesis reactor agitator motor 39 and monitor its operation using the current display 34. Agitator 67 utilizes a combination of two-blade CBY and three-blade swept impellers. The axial flow pattern of the CBY impellers reduces nucleation contact, while the three-blade swept impellers enhance circulation. This combined structure reduces rotational speed, reduces power consumption, and promotes uniform crystal growth. Open the steam line 53 feed valve 52 and the condensate line 56 shut-off valve 17. The temperature is raised to the initial reaction temperature and then maintained. CEC enters the addition tank via the line and shut-off valve 17. The liquid level meter 38 interlocks to control the feed rate. The synthesis reactor feed flowmeter is set to a value, and the regulating valve controls the feed. The shut-off valve 17 of the cooling circulating water line 59 and the return water line 44 is interlocked and controlled based on the reading of the thermometer 51. The vaporized DMC is recovered by the condenser 42, and the circulating water is supplied to the return line 125 for cooling. The bottom temperature measurement point 48 monitors the post-cooling temperature. The shut-off valve 17 forms a liquid seal to prevent direct DMC venting. The pressure measurement point 50 monitors the reaction pressure.

[0040] After the reaction is complete, the material enters the temporary storage tank through shut-off valve 17. The agitator 67 operates continuously, while the bottom hose pump 63 and accumulator 64 provide a stable pressure flow. The material enters the filtration zone of the rotary drum filter press 91 via a pipeline. Temperature and pressure measurement points 50 monitor the feed status. The filtered mother liquor is discharged into the mother liquor tank 104 and transported downstream via the transfer pump 92 and liquid level control valve 102. The filter cake enters the tertiary washing zone in sequence: the primary wash liquid comes from the secondary wash liquid tank 100 and is controlled by the transfer pump 92 and pressure regulating valve 87; the secondary wash liquid comes from the tertiary wash liquid tank 96 and is controlled by the transfer pump 92 and pressure regulating valve 87; and the tertiary wash liquid comes from the filter cloth rinse liquid tank 107 and is controlled by the transfer pump 92, pressure regulating valve 87, and flowmeter 88. The wash liquid is recycled step by step. The drying zone uses nitrogen pipeline 73 for pre-drying. The gas-liquid mixture enters the drying gas-liquid tank 111 and, when the liquid level is high, is transported to the filter cloth rinse liquid tank 107. The unloading area is unloaded by scraper, discharge gas backflushing and gravity, and the filter cake falls into the paddle dryer 119. The filter cloth flushing liquid pump flushes the residual filter residue.

[0041] Potassium chloride in paddle dryer 119 enters scraper conveyor 146 through discharge port 16. Multiple scraper conveyors 146 relay the potassium chloride to the incineration plant. The entire system operates under a sealed, slightly negative pressure to prevent the volatilization of organic matter. During the drying process, DMC vaporizes and liquefies through gas condenser 144. It is then stored in temporary storage tank 140. When the liquid level is high, it is transferred to the DMC storage tank via transfer pump 92 and self-cleaning filter 143. The condenser 42 is regularly flushed, and the salt residue at the bottom of the temporary storage tank 140 is cleaned.

[0042] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A fluoroethylene carbonate automatic synthesis and separation control system, characterized in that: include: A feeding unit is used for realizing automatic feeding of potassium fluoride, comprising a ton bag hoisting frame (1), an electric hoist (3), a ton bag feeding box (6), a bag breaking mechanism (7) and a potassium fluoride silo, wherein the ton bag hoisting frame (1) is connected to the electric hoist (3), a bag breaking mechanism (7) is arranged in the ton bag feeding box (6), a blade (8) is arranged on the bag breaking mechanism (7), and the potassium fluoride silo is arranged below the ton bag feeding box (6) and is provided with a weighing module (9); A dissolving unit for dissolving potassium fluoride, comprising a potassium fluoride dissolving kettle (26), a stirring device (27), a feeding pipeline and temperature and pressure measuring instruments, wherein the stirring device (27) comprises a stirring motor (62) and an ammeter (28), and the feeding pipeline is provided with a flow meter (88) and a shut-off valve (17); A synthesis unit for synthesizing fluoroethylene carbonate, comprising an FEC synthesis reactor, a stirring blade (67) assembly, a heating and cooling system, and feed and discharge pipelines, wherein the stirring blade (67) assembly is a combination of a downward pressure two-blade CBY blade and a three-blade swept blade, the heating system comprises a steam pipeline (53), and the cooling system comprises a circulating water line; A separation unit for separating synthetic products, comprising an FEC temporary storage kettle, a hose pump (63), an accumulator (64) and a drum filter press (91), wherein the FEC temporary storage kettle is provided with a stirring paddle (67), the outlet of the hose pump (63) is connected to the accumulator (64), and the drum filter press (91) comprises a filtration zone, at least three washing zones and a drying zone; A drying and conveying unit is used for drying and conveying potassium chloride salt, comprising a paddle dryer (119), a gas condenser (144), a temporary storage tank (140) and a scraper conveyor (146). The inlet pipeline of the paddle dryer (119) is provided with a sight glass (22), the gas condenser (144) is provided with a circulating water system and a flushing pipeline, and the scraper conveyor (146) adopts a closed micro-negative pressure conveying method.

2. The automatic synthesis and separation control system of fluoroethylene carbonate according to claim 1, characterized in that: In the feeding unit, a dust discharge port (10) is provided on the side of the ton bag feeding box (6), the dust discharge port (10) is connected to a dust collector (11), a cloth bag (12) and a nitrogen back-flushing device (14) are provided in the dust collector (11), a potassium fluoride discharge port (15) in the ton bag feeding box (6) is provided with a shut-off valve (17) and a pneumatic vibrator (20), and a sight glass (22) is provided below the discharge port (15).

3. The automatic synthesis and separation control system of fluoroethylene carbonate according to claim 1, characterized in that: In the synthesis unit, the FEC synthesis reactor is provided with a condenser (42), the condenser (42) includes a circulating water supply and return pipeline (125), a venting pipeline (46) and a temperature measuring point (48), and a shut-off valve (17) is provided at the bottom of the venting pipeline (46) to form a liquid seal to prevent DMC from being directly vented after vaporization.

4. The automatic synthesis and separation control system of fluoroethylene carbonate according to claim 1, characterized in that: In the separation unit, the washing area of ​​the rotary drum filter press (91) includes a primary washing area, a secondary washing area, and a tertiary washing area. The primary washing area is connected to a secondary washing liquid tank (100), the secondary washing area is connected to a tertiary washing liquid tank (96), and the tertiary washing area is connected to a filter cloth flushing liquid tank (107). Each washing area is provided with a delivery pump (92), a pressure regulating valve (87), and a pressure measuring point (50).

5. The automatic synthesis and separation control system of fluoroethylene carbonate according to claim 1, characterized in that: In the drying and conveying unit, the outlet of the gas condenser (144) is connected to a temporary storage tank (140), the temporary storage tank (140) is provided with a liquid level gauge (38) and a conveying pump (92), the outlet of the conveying pump (92) is connected to a self-cleaning filter (143), and the scraper conveyor (146) adopts a multiple-unit relay conveying method. The entire conveying process is a system-enclosed micro-negative pressure operation.

6. The automatic synthesis and separation control system of fluoroethylene carbonate according to claim 1, characterized in that: The system further comprises a nitrogen balancing system, wherein the nitrogen balancing system comprises a plurality of nitrogen pipelines (73) for balancing the pressure of the mother liquid tank (104), the washing liquid tank and the equipment respectively. The nitrogen pipelines (73) are provided with a self-operated regulating valve (83) and a pressure measuring point (50).

7. The automatic synthesis and separation control system of fluoroethylene carbonate according to claim 1, characterized in that: The potassium fluoride dissolving kettle (26) and the FEC synthesis kettle are both provided with a weighing module (9), and the weighing module (9) is used for interlocking control of the feed amount. The FEC synthesis kettle is also provided with a pressure measuring point (50) and a temperature gauge (32) for monitoring the pressure and temperature of the reaction process.

8. The automatic synthesis and separation control system of fluoroethylene carbonate according to claim 1, characterized in that: The drying area of ​​the rotary drum filter press (91) is pre-dried using a nitrogen pipeline (73). The nitrogen pipeline (73) is provided with a flow meter (88), a pressure regulating valve (87) and a pressure measuring point (50). The gas-liquid mixture generated by the pre-drying enters a drying gas-liquid tank (111). The drying gas-liquid tank (111) is provided with a liquid level meter (38), a delivery pump (92) and a venting pipeline (46).

9. The automatic synthesis and separation control system of fluoroethylene carbonate according to claim 1, characterized in that: The paddle dryer (119) is provided with a steam pipeline (53) and a circulating water supply and return pipeline (125). The steam pipeline (53) is provided with a flow meter (88), a regulating valve, a pressure measuring point (50) and a temperature measuring point (70). The paddle dryer (119) body is provided with a temperature measuring point (70) for controlling the drying temperature according to the residual DMC content of potassium chloride salt.

10. A fluoroethylene carbonate automatic synthesis and separation control system according to any one of claims 1 to 9, characterized in that: The system realizes full-process automated operation through a DCS automatic control program, including the lifting, bag breaking, and unloading of potassium fluoride ton bags, and the dissolution, synthesis, separation, drying, and transportation of the materials. The DCS automatic control program can interlock and control the operation of each device based on the data of instruments such as a weighing module (9), a flow meter (88), a temperature gauge (32), and a pressure gauge (31).

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