A multi-field coupling reinforced separation and purification system and method

Abstract

The application discloses a multi-field coupling reinforced separation and purification system and method, and belongs to the field of separation and purification technology. The system comprises a vacuum pump, at least one set of deep-cold cyclone separation device, at least one set of electric field reinforced molecular distillation device and a control system. The vacuum pump is communicated with the deep-cold cyclone separation device and the electric field reinforced molecular distillation device respectively, and provides a vacuum environment for the two. The deep-cold cyclone separation device comprises a cyclone separator and a cavity formed by an inner cylinder and an outer cylinder of the deep-cold cyclone separation device, and is provided with a gas collecting hood and liquid inlet and outlet valves. The electric field reinforced molecular distillation device comprises an outer cylinder and an inner cylinder of the electric field reinforced molecular distillation device, a liquid inlet pipe and a liquid inlet valve. The application is suitable for a deep-cold medium, a rare gas and a mixed system of the liquefied rare gas and a part of organic small molecule systems. The self-adaptive operation of different material systems and target purity requirements can be realized through the synergistic adjustment of vacuum, pressure and electric field parameters, and the feasibility of engineering amplification and continuous operation is improved.

Description

Technical Field

[0001] This invention relates to the field of chemical separation and molecular distillation, specifically including a separation and purification system and method enhanced by multi-field coupling. Background Technology

[0002] Molecular distillation, also known as short-path distillation, is a liquid-liquid separation or volatile component separation technique performed under high vacuum conditions. It utilizes the vapor pressure or boiling point differences of different components in a mixed system, allowing lower-boiling-point or higher-vapor-pressure components to preferentially escape and condense at a lower distillation temperature and shorter heating time, thus achieving the separation of light and heavy components. This technology features high system vacuum, low distillation temperature, short material heating time, and high separation efficiency, and has been widely applied in fine chemicals, functional oils and natural product extraction, high-purity gas and cryogenic medium purification, and the preparation of small organic molecule intermediates. Compared to extraction and adsorption separation methods, distillation typically does not require the introduction of solvents other than those used in the system, which helps avoid the risk of secondary contamination from added solvents. Therefore, it is suitable for applications requiring high product purity and quality stability. In engineering implementation, it is often combined with thin-film / scraped film, centrifugal film formation, vacuum condensation, and process control to achieve continuous or semi-continuous operation.

[0003] However, existing molecular distillation apparatuses and systems still face certain technical bottlenecks when dealing with higher purity, higher throughput, and more complex multi-component systems. On the one hand, while centrifugal rotary molecular distillers can promote film formation and enhance mass transfer, they still suffer from relatively complex structures, high manufacturing and maintenance costs, inconvenient operation and adjustment, and limited improvements in product purity and recovery rates. On the other hand, scraped-film molecular distillation equipment is prone to droplet splashing and vapor entrainment during operation. Entrained droplets, after accumulating on the condensation surface, can easily cause cross-contamination of the distillate, leading to a decrease in product purity and reduced separation efficiency. In addition, uneven feed distribution, fluctuations in liquid film thickness, and inconsistent temperature fields can further reduce separation efficiency and product quality, making it difficult to consistently obtain high-purity products. Furthermore, existing devices mostly use boiling point or vapor pressure difference as the main separation driving force. For multi-component systems with significant differences in charge characteristics or polarizability response and requiring higher selectivity, there is often a lack of enhanced separation methods that are coordinated with the distillation process. This may lead to an increase in the number of purification stages, increased energy consumption, and larger equipment size, making it difficult to simultaneously achieve high purity, high yield, low energy consumption, and operational stability.

[0004] Based on the aforementioned problems, there is an urgent need to provide a multi-stage purification device and method for multi-component systems. This invention introduces a cyclone separation unit under high vacuum and cryogenic conditions, utilizing the differences in boiling points and condensation characteristics of different components to achieve pre-separation and load distribution. Furthermore, an electric field enhancement method is introduced in the molecular distillation stage, further improving mass transfer efficiency and separation selectivity by utilizing the differences in the charged characteristics and electrical responses of different components. This forms a multi-field coupled, multi-stage tandem purification route combining cryogenic cyclone separation and electric field-enhanced molecular distillation. Compared with a single distillation mechanism, this invention can reduce the load on subsequent distillation units at the front end and suppress purity fluctuations caused by entrainment; in the distillation section, the separation driving force is enhanced through the electric field, improving product purity and quality stability; simultaneously, relying on multi-stage tandem separation and process controllability, the number of repeated distillations and unnecessary energy consumption are reduced, thereby improving the system's applicability and engineering scale-up potential for cryogenic media, rare gas mixtures, and some small organic molecule systems. Summary of the Invention

[0005] This invention discloses a multi-field coupled enhanced separation and purification system and method. The aim is to address the problems existing in current molecular distillation or short-path distillation devices during high-purity extraction and purification processes, such as insufficient separation selectivity, purity fluctuations caused by entrainment and cross-contamination, increased energy consumption and equipment size due to the increased number of purification stages in complex multi-component systems, and difficulty in coordinating and optimizing process parameters. This invention proposes a multi-stage purification system and method that couples cryogenic cyclone pre-separation with electric field-enhanced molecular distillation to achieve multi-stage separation and purification of multi-component materials, and improve the purity and operational stability of the purified products.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a multi-field coupled enhanced separation and purification system, characterized in that: the system includes a vacuum pump, at least one set of cryogenic cyclone separation device, at least one set of electric field enhanced molecular distillation device, and a control system; the vacuum pump is connected to the cryogenic cyclone separation device and the electric field enhanced molecular distillation device respectively, providing a vacuum environment for both; the gas phase enrichment stream outlet of the cryogenic cyclone separation device is fluidly connected to the liquid inlet pipe of the electric field enhanced molecular distillation device, so that the enriched stream obtained by cryogenic cyclone separation is used as the feed for electric field enhanced molecular distillation, thereby forming at least one stage of cryogenic cyclone pre-separation-electric field enhanced molecular distillation coupled purification path. The cryogenic cyclone separator includes a cyclone separator and a cavity formed by the inner cylinder and outer cylinder of the cryogenic cyclone separator. It is equipped with a gas collecting hood, a distributor, a vaporization pipe, a liquid inlet / outlet valve, and a discharge valve. The gas collecting hood is used to collect and discharge the gas-enriched stream, the discharge valve is used to discharge the residual liquid, and the liquid inlet / outlet valve is used to discharge the liquid stream. Therefore, the cryogenic cyclone separator has a gas-enriched stream outlet and a residual liquid outlet, and optionally a liquid output port to achieve pre-separation and load distribution. The electric field enhanced molecular distillation apparatus includes an outer cylinder and an inner cylinder, an inlet pipe and an inlet valve, a brushing structure for forming and renewing a liquid film on the surface of the inner cylinder, and an electric field application structure consisting of a voltage generator, an electrode ring, and a collecting electrode mesh. A collecting funnel is also provided for collecting the distillate. The voltage generator is used to create an electric field in the distillation space, enabling different components to achieve differentiated effects based on their charge characteristics or differences in electrical response, thereby enhancing the liquid film mass transfer process and the vapor and molecular migration process and improving separation selectivity.

[0007] According to the present invention, the system includes at least two sets of cryogenic cyclone separators and at least two sets of electric field-enhanced molecular distillation devices. Each device is connected in series to form at least two stages of the coupled purification path. The purified product output of the preceding electric field-enhanced molecular distillation device is fluidly connected to the feed end of the following cryogenic cyclone separator to achieve multi-stage purification. Preferably, pressure matching is achieved between adjacent stages through the vacuum regulating valve, pressure controller, pressure boosting valve, and pressure boosting pipe, ensuring stable flow of the purified product from the preceding stage when transported to the following stage and reducing the risk of flash evaporation or entrainment. The number of stages in the multi-stage series connection can be set to two, three, or four stages depending on the target purity and raw material composition to achieve progressive load distribution and progressive purification.

[0008] According to the present invention, the cryogenic cyclone separator further includes a cryogenic compression device, which cooperates with the cryogenic cyclone separator to provide cryogenic operating conditions.

[0009] According to the present invention, the inner cylinder of the cryogenic cyclone separator and the outer cylinder of the cryogenic cyclone separator constitute a double-layer cylinder structure to form a cryogenic cavity and reduce the influence of external heat leakage on the stability of cyclone separation.

[0010] According to the present invention, the cryogenic cyclone separator further includes a flow divider, a gas collecting hood, and a vaporization tube; the gas collecting hood is disposed at the upper part of the cavity to collect and discharge the gas-phase enriched flow, the flow divider is disposed at the lower part to realize the flow separation after gas-liquid phase separation, and the vaporization tube is used to provide a controllable flow guiding or heat exchange vaporization path for the steam or volatile components generated during the separation process.

[0011] According to the present invention, the liquid inlet / outlet valve and the discharge valve are disposed at the lower part to discharge the liquid phase stream and residual liquid. Preferably, the discharge valve is used to independently discharge the residual liquid, and the liquid inlet / outlet valve is used to independently discharge the liquid phase stream, thereby enabling the gas phase enrichment stream, the liquid phase stream and the residual liquid to be discharged separately and facilitate graded recovery or reflux treatment.

[0012] According to the present invention, the cryogenic cyclone separator further includes a vacuum regulating valve, a pressure controller, a booster valve, a vacuum valve, a vacuum gas delivery valve, and a booster pipe. The vacuum regulating valve, vacuum valve, and vacuum gas delivery valve are used in conjunction with a vacuum pump to form and regulate the vacuum state required for separation. The pressure controller, booster valve, and booster pipe are used to control the pressure state to achieve pressure matching and stable delivery during the feeding, enrichment flow output, and residual liquid discharge processes. The vacuum regulating valve is used to regulate the vacuum level of the separation chamber. The vacuum valve is used for start-stop isolation. The vacuum gas delivery valve is used for gas extraction or displacement channel control to improve the stability of the system start-up and shutdown processes. Furthermore, the pressure controller and booster valve work together to control the delivery pressure difference between the cryogenic cyclone separator and the electric field enhanced molecular distillation device to reduce the impact of delivery fluctuations on the formation of the distillate film.

[0013] According to the present invention, the cryogenic cyclone separator further includes an electromagnetic stirrer, which works in conjunction with the cyclone separator to form a cyclone field. Furthermore, the electromagnetic stirrer's operating state is adjusted by a control system to make the cyclone intensity controllable, thereby adapting to the pre-separation requirements of different material systems and improving the stability of the enriched flow.

[0014] According to the present invention, the cyclone separator includes a rotating shaft with a magnetic core, cyclone blades, a cyclone separator housing, and a limiting support. The cyclone blades are disposed on the rotating shaft with the magnetic core to form a cyclone driving structure, and the limiting support is used to position and limit the rotating shaft. The rotating shaft with the magnetic core forms a magnetic coupling transmission with an external drive to achieve cyclone driving under sealed conditions, thereby reducing the risk of leakage and improving reliability in cryogenic vacuum environments.

[0015] According to the present invention, the electric field enhanced molecular distillation apparatus further includes an outer cylinder vacuum valve and a sealing ring. The outer cylinder vacuum valve is used to connect the outer cylinder of the electric field enhanced molecular distillation apparatus with a vacuum pump to form a distillation vacuum environment, thereby reducing the influence of non-condensable gases on distillation efficiency and the stability of the electric field. The sealing ring is used to achieve a sealed fit between the outer cylinder and the inner cylinder of the electric field enhanced molecular distillation apparatus.

[0016] According to the present invention, the liquid brushing structure includes a magnetic stirrer base, a spiral support, a magnetic core rotor, a liquid brushing disc, a liquid brushing support rod, and a liquid brushing head. The magnetic core rotor cooperates with an external drive at the magnetic stirrer base and drives the liquid brushing disc to rotate, so that the liquid brushing support rod and the liquid brushing head support the liquid brushing disc and brush, renew, and disturb the liquid film on the surface of the inner cylinder of the electric field enhanced molecular distillation device to form and maintain the liquid film state.

[0017] According to the present invention, the electric field applying structure further includes a positive electrode wire and a negative electrode wire. The electrode ring and the collecting electrode mesh are electrically connected to the voltage generator through the positive electrode wire and the negative electrode wire to form an electric field in the distillation space. The collecting electrode mesh cooperates with the collecting funnel to collect the distillate and export the purified product through the purified gas-liquid delivery valve. The electric field enhanced molecular distillation device is also equipped with a residual liquid delivery valve for exporting residual liquid and a vent valve for venting. Furthermore, the electric field parameters output by the voltage generator can be adjusted by the control system to adapt to different material systems and target separation selectivity requirements.

[0018] According to the present invention, the electric field formed by the electric field applying structure is used to enhance the mass transfer process of the liquid film on the surface of the inner cylinder of the electric field enhanced molecular distillation device, and to guide or selectively affect the vapor or molecular migration process generated by distillation, so as to improve the separation selectivity of the target component.

[0019] According to the present invention, the multi-component material to be separated may be any one or more of the following: cryogenic medium and its mixture, rare gas and its liquefied mixture system, or organic small molecule mixture system.

[0020] This invention also provides a method for multi-stage purification using cryogenic cyclone separation and electric field-enhanced molecular distillation, the steps of which are as follows: S1) Start the vacuum pump to put the cryogenic cyclone separator and the electric field enhanced molecular distillation device into a vacuum environment, and adjust the vacuum state required for separation through the vacuum degree regulating valve, vacuum valve and vacuum gas supply valve of the cryogenic cyclone separator, and adjust the vacuum state required for distillation through the outer cylinder vacuum valve of the electric field enhanced molecular distillation device. S2) Start the cryogenic compression unit to provide cryogenic conditions to the cryogenic cyclone separator. Send the multi-component materials to be separated into the cryogenic cyclone separator. Under the action of the cyclone field formed by the electromagnetic stirrer and the cryogenic conditions, pre-separation is achieved. The gas phase enriched flow is discharged by the gas collection hood, and the liquid phase flow and residual liquid are discharged by the liquid inlet and outlet valves. The pressure status is controlled by the pressure controller, pressure boosting valve and pressure boosting pipe. S3) Open the liquid inlet valve to allow the gas-phase enriched flow (or the enriched flow formed by conversion and collection) to enter the electric field enhanced molecular distillation device through the liquid inlet pipe, and form a liquid film on the surface of the inner cylinder of the electric field enhanced molecular distillation device; start the magnetic stirrer base and cooperate with the magnetic core rotor to drive the liquid brushing disc, liquid brushing support rod and liquid brushing head to brush, update and disturb the liquid film in order to carry out molecular distillation. S4) Start the voltage generator and apply voltage to the electrode ring and the collecting electrode grid through the positive and negative electrode wires to form an electric field in the distillation space. This allows different components to achieve differentiated effects based on their charge characteristics or differences in electrical response, thereby simultaneously enhancing the liquid film mass transfer process and the vapor or molecular migration process and improving separation selectivity. S5) The distillate obtained from distillation is collected at the collecting electrode mesh and collecting funnel and discharged as a purified product through the purified gas-liquid delivery valve. At the same time, the residual liquid is discharged through the residual liquid delivery valve and vented through the vent valve when necessary. Herein, steps S2-S5 constitute a coupled purification step of cryogenic cyclone pre-separation-electric field enhanced molecular distillation, and the coupled purification step is performed at least once. When the device contains at least two stages of coupled purification path, the purified product discharged from the previous stage electric field enhanced molecular distillation device is sent to the next stage cryogenic cyclone separation device to repeat the coupled purification step, thereby realizing multi-stage purification. The control system is connected to the pressure controller, pressure boosting valve and voltage generator of the cryogenic cyclone separation device through an electromagnetic controller and control signal line to coordinate the adjustment of pressure state and electric field parameters.

[0021] Compared with the prior art, the beneficial effects of the present invention include, but are not limited to, the following aspects: 1) Improved separation selectivity and purity. This invention couples cryogenic cyclone pre-separation with electric field-enhanced molecular distillation. First, pre-enrichment is achieved by utilizing the differences in boiling points or condensation characteristics of the components. Then, electric field-enhanced separation is performed by utilizing the differences in charge characteristics or electrical response, thereby improving the separation driving force and selectivity, enhancing the purity of the purified product, and improving quality stability.

[0022] 2) Reduce the risk of entrainment and cross-contamination. Pre-distributing the stream through cyclone separation and gas-liquid splitting structures, combined with brushing and liquid film renewal within the distillation unit, helps reduce cross-contamination of distillates caused by droplet splashing and vapor entrainment, thus reducing purity fluctuations.

[0023] 3) Multi-stage series connection and more reasonable load distribution. The multi-stage cryogenic cyclone pre-separation-electric field enhanced molecular distillation series connection allows the separation load of each stage to be distributed step by step, reducing the processing load of subsequent distillation stages. When the target purity is achieved, the number of repeated distillations can be reduced, improving the overall purification efficiency and process controllability.

[0024] 4) Wider applicability and greater adjustability of operating conditions. The device and method are applicable to cryogenic media, rare gases and their liquefied mixtures, as well as some small organic molecule systems; at the same time, adaptive operation can be achieved for different material systems and target purity requirements through coordinated adjustment of vacuum, pressure and electric field parameters, improving the feasibility of engineering scale-up and continuous operation. Attached Figure Description

[0025] Figure 1 A schematic diagram of the process flow for a separation and purification system with enhanced multi-field coupling; Figure 2 for Figure 1 Schematic diagram of a cryogenic cyclone separator; Figure 3 for Figure 2 Schematic diagram of a cyclone separator; Figure 4 This is a schematic diagram of an electric field-enhanced molecular distillation apparatus.

[0026] The components include: 1. Vacuum pump; 2. Cryogenic cyclone separator I; 201. Vacuum regulating valve; 202. Pressure controller; 203. Pressure booster valve; 204. Vacuum valve; 205. Vacuum gas delivery valve; 206. Pressure booster pipe; 207. Cyclone separator; 2071. Rotating shaft with magnetic core; 2072. Cyclone blades; 2073. Cyclone separator housing; 2074. Limiting support; 208. Inner cylinder of cryogenic cyclone separator; 209. Outer cylinder of cryogenic cyclone separator; 210. Gas collecting hood; 211. Vaporization pipe; 212. Flow divider; 213. Liquid inlet / outlet valve; 214. Discharge valve. 3. Liquid helium to be purified; 4. First-stage purified liquid helium; 5. Cryogenic compression device; 6. Electromagnetic stirrer; 7. Electric field enhanced molecular distillation apparatus I; 701. Outer cylinder of the electric field enhanced molecular distillation apparatus; 702. Liquid inlet pipe; 703. Liquid inlet valve; 704. Magnetic stirrer base; 705. Spiral support; 706. Vacuum valve of the outer cylinder; 707. Inner cylinder of the electric field enhanced molecular distillation apparatus; 708. Sealing ring; 709. Positive electrode wire; 710. Voltage generator; 711. Negative electrode wire; 712. Purified gas-liquid delivery valve; 713. Residual liquid 714. Delivery valve; 715. Vent valve; 716. Magnetic core rotor; 717. Brushing disc; 718. Brushing support rod; 719. Brushing head; 720. Electrode ring; 721. Collecting electrode mesh; 722. Collecting funnel; 8. Stage I purification residue; 9. Stage II purified liquid helium; 10. Control signal line; 11. Electromagnetic controller; 12. No. II cryogenic cyclone separator; 13. Stage II compressed liquid helium; 14. Stage III purified liquid helium; 15. No. II electric field enhanced molecular distillation device; 16. Stage II purification residue; 17. Stage IV purified liquid helium; 18. Storage device. Detailed Implementation

[0027] The present invention will be further described in detail below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0028] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0029] Example 1 like Figure 2As shown, the cryogenic cyclone separator in this embodiment can be either a No. 1 cryogenic cyclone separator 2 or a No. 2 cryogenic cyclone separator 12, and the structures can be the same or equivalent. The No. 1 cryogenic cyclone separator 2 includes a vacuum regulating valve 201, a pressure controller 202, a booster valve 203, a vacuum valve 204, a vacuum gas delivery valve 205, a booster pipe 206, a cyclone separator 207, an inner cylinder 208 of the cryogenic cyclone separator, an outer cylinder 209 of the cryogenic cyclone separator, a gas collecting hood 210, a vaporization pipe 211, a distributor 212, a liquid inlet / outlet valve 213, and a discharge valve 214.

[0030] The cryogenic cyclone separator inner cylinder 208 and the cryogenic cyclone separator outer cylinder 209 form a cavity and a cryogenic cavity structure. The cryogenic compression device 5 works with the cryogenic cavity to provide and maintain the cryogenic working condition. The vacuum pump 1 is connected to the cryogenic cyclone separator through the vacuum degree regulating valve 201, the vacuum valve 204 and the vacuum gas delivery valve 205 to establish and regulate the vacuum state required for separation. The pressure controller 202 works with the pressure boosting valve 203 and the pressure boosting pipe 206 to control the pressure state so as to achieve pressure matching and stable delivery in the feeding, enrichment flow output and residual liquid discharge process.

[0031] A cyclone separator 207 is installed inside the inner cylinder 208 of the cryogenic cyclone separator to create a swirling flow field within the separation chamber. An electromagnetic stirrer 6 is arranged on the outside of the device and works in conjunction with the cyclone separator 207 to achieve swirling flow formation under a sealed and cryogenic vacuum environment. A gas collecting hood 210 is located at the upper part of the chamber to collect the upper gas phase and discharge the gas-rich flow. A flow divider 212 is located at the lower part of the device to achieve stable flow separation after gas-liquid phase separation. A liquid inlet / outlet valve 213 is located at the lower part to discharge the liquid flow. A discharge valve 214 is used to discharge residual liquid. A vaporization pipe 211 is located inside the chamber and works in conjunction with the gas collecting hood 210 and the flow divider 212 to provide a controllable flow or heat exchange vaporization path for the vapor or volatile components generated during the separation process, thereby reducing entrainment and improving pre-separation stability. Thus, the cryogenic cyclone separator has at least a gas-rich flow outlet and a residual liquid outlet, and optionally a liquid output port to achieve pre-separation and load distribution.

[0032] like Figure 3 As shown, the cyclone separator 207 includes a rotating shaft 2071 with a magnetic core, cyclone blades 2072, a cyclone separator housing 2073, and a limiting support 2074. The cyclone blades 2072 are mounted on the rotating shaft 2071 with a magnetic core to form a cyclone drive structure. The limiting support 2074 is used to position and limit the rotating shaft 2071 to ensure the stable operation of the cyclone separator 207 under cryogenic vacuum conditions. The cyclone separator housing 2073 is used to form the structural support and flow channel boundary of the cyclone separator.

[0033] like Figure 4 As shown, the electric field enhanced molecular distillation apparatus in this embodiment can be electric field enhanced molecular distillation apparatus 7 (or electric field enhanced molecular distillation apparatus 15, the structure of which can be the same or equivalent). Electric field enhanced molecular distillation apparatus 7 includes an outer cylinder 701, an inlet pipe 702, an inlet valve 703, a magnetic stirrer base 704, a spiral support 705, an outer cylinder vacuum valve 706, an inner cylinder 707, a sealing ring 708, a positive electrode wire 709, a voltage generator 710, a negative electrode wire 711, a purified gas-liquid delivery valve 712, a residual liquid delivery valve 713, a vent valve 714, a magnetic core rotor 715, a brushing disc 716, a brushing support rod 717, a brushing head 718, an electrode ring 719, a collecting electrode mesh 720, and a collecting funnel 721.

[0034] The outer cylinder 701 and inner cylinder 707 of the electric field enhanced molecular distillation apparatus are arranged coaxially. A sealing ring 708 is used to achieve a sealing fit between the outer cylinder 701 and the inner cylinder 707. The outer cylinder vacuum valve 706 is used to connect the outer cylinder 701 to the vacuum pump 1 to form the vacuum environment required for distillation. The gas-phase enriched stream (or the enriched stream formed by conversion and collection) exported from the cryogenic cyclone separator enters the electric field enhanced molecular distillation apparatus 7 through the liquid inlet pipe 702 and is controlled by the liquid inlet valve 703 to enter the distillation space.

[0035] To achieve stable film formation and liquid film renewal, a magnetic stirrer base 704 is located outside the device and magnetically coupled to a magnetic core rotor 715. The magnetic core rotor 715 is located inside the distillation apparatus and connected to a brushing disc 716. A brushing support rod 717 and a brushing head 718 are mounted on the brushing disc 716, and a spiral support 705 is used to position and support the brushing structure. During operation, the magnetic stirrer base 704 drives the magnetic core rotor 715 to rotate the brushing disc 716, causing the brushing head 718 to form and continuously renew a liquid film on the surface of the inner cylinder 707 of the electric field-enhanced molecular distillation apparatus. The brushing head brushes, renews, and agitates the liquid film to shorten the mass transfer path and suppress droplet entrainment.

[0036] To achieve electric field-enhanced separation, the voltage generator 710 is electrically connected to the electrode ring 719 and the collecting electrode grid 720 via the positive electrode wire 709 and the negative electrode wire 711, respectively, creating an electric field in the distillation space. This electric field causes different components to exhibit differentiated effects based on their charge characteristics and electrical response differences, thereby synergistically enhancing the liquid film mass transfer process and the vapor and molecular migration processes, and improving separation selectivity. The distillate obtained is captured at the collecting electrode grid 720 and collected by the collecting funnel 721, then discharged through the purified gas-liquid delivery valve 712; the residual liquid is discharged through the residual liquid delivery valve 713; and the vent valve 714 is used for venting or depressurization. The control system uses an electromagnetic controller 11, which is connected to the pressure controller 202, the pressure boosting valve 203, and the voltage generator 710 via the control signal line 10, to achieve coordinated adjustment of pressure status and electric field parameters, thereby improving system operational stability and process controllability.

[0037] Example 2 like Figure 1 As shown, this embodiment provides a process flow and method for multi-stage purification using cryogenic cyclone separation and electric field-enhanced molecular distillation. The system includes a vacuum pump 1, a cryogenic cyclone separator I 2, an electric field-enhanced molecular distillation device I 7, a cryogenic cyclone separator II 12, an electric field-enhanced molecular distillation device II 15, a cryogenic compression device 5, an electromagnetic stirrer 6, an electromagnetic controller 11, a control signal line 10, and a collection and storage device 18. The liquid helium 3 to be purified enters the cryogenic cyclone separator I 2, and the gas-phase enriched stream is drawn off and enters the electric field-enhanced molecular distillation device I 7, yielding first-stage purified liquid helium 4, while simultaneously producing first-stage purified residual liquid 8. The first-stage purified helium 4 is fed into the second-stage cryogenic cyclone separator 12 as a subsequent stage feed. Under the action of the second-stage cryogenic cyclone separation and pressure regulation, it forms the second-stage compressed helium 13. The second-stage compressed helium 13 enters the second-stage electric field enhanced molecular distillation device 15 to form the second-stage coupled purification path. After the second-stage coupled purification, the second-stage purified helium 9 is obtained and the second-stage purified residue 16 is produced. If higher purity is required, the second-stage purified helium 9 can continue to enter the subsequent stages to obtain the third-stage purified helium 14 and the fourth-stage purified helium 17, and finally enter the collection and storage device 18.

[0038] Based on the above system, the method steps of this embodiment are as follows: S1) Start vacuum pump 1 to put the No. I cryogenic cyclone separator 2 and the No. I electric field enhanced molecular distillation device 7 into a vacuum environment; adjust the vacuum state required for separation through vacuum degree regulating valve 201, vacuum valve 204 and vacuum gas supply valve 205, and adjust the vacuum state required for distillation through outer cylinder vacuum valve 706.

[0039] S2) The cryogenic compression device 5 is started to provide cryogenic conditions to the No. 1 cryogenic cyclone separator 2, and the liquid helium 3 to be purified is sent into the No. 1 cryogenic cyclone separator 2. Under the action of the cyclone field formed by the electromagnetic stirrer 6 and the cyclone separator 207, pre-separation is achieved. The gas phase enriched flow is collected and discharged by the gas collection hood 210. The flow divider 212 realizes the separation and stabilization of the gas-liquid phase. The liquid phase flow is discharged by the liquid inlet and outlet valve 213, and the residual liquid is discharged by the discharge valve 214. At the same time, the pressure status is controlled by the pressure controller 202, the pressure boosting valve 203 and the pressure boosting pipe 206 to achieve pressure matching and stable delivery.

[0040] S3) Open the liquid inlet valve 703 to allow the gas-phase enriched stream (or the enriched stream formed by conversion and aggregation) to enter the No. I electric field enhanced molecular distillation device 7 through the liquid inlet pipe 702, and form a liquid film on the surface of the inner cylinder 707 of the electric field enhanced molecular distillation device; start the magnetic stirrer base 704, and drive the brushing disk 716 to rotate in conjunction with the magnetic core rotor 715, so that the brushing support rod 717 and the brushing head 718 brush, renew and disturb the liquid film to carry out molecular distillation and suppress entrainment.

[0041] S4) Start the voltage generator 710, apply voltage to the electrode ring 719 and the collecting electrode grid 720 through the positive electrode wire 709 and the negative electrode wire 711 to form an electric field in the distillation space, so that different components can obtain differentiated effects based on their charge characteristics and electrical response differences, thereby simultaneously enhancing the liquid film mass transfer process and the vapor or molecular migration process and improving separation selectivity.

[0042] S5) The distillate obtained from distillation is captured at the collecting electrode grid 720 and collected by the collecting funnel 721. It is then discharged through the purified gas-liquid transfer valve 712 to form the first-stage purified liquid helium 4. At the same time, the residual liquid is discharged through the residual liquid transfer valve 713 to form the first-stage purified residual liquid 8. When necessary, it is vented through the vent valve 714.

[0043] Steps S2-S5 constitute a coupled purification step of cryogenic cyclone pre-separation-electric field enhanced molecular distillation, which is performed at least once. When the system contains at least two stages of coupled purification paths, the first-stage purified liquid helium 4 from the previous stage electric field enhanced molecular distillation device 7 is sent to the second-stage cryogenic cyclone separator 12 for second-stage pre-separation under cryogenic and cyclone separation, forming a second-stage compressed liquid helium 13. The second-stage compressed liquid helium 13 is then sent to the second-stage electric field enhanced molecular distillation device 15 to repeat steps S3-S5, thereby obtaining a second-stage purified liquid helium 9 and producing a second-stage purified residue 16. To further improve purity, the second-stage purified liquid helium 9 can continue to enter subsequent stages to obtain a third-stage purified liquid helium 14 and a fourth-stage purified liquid helium 17, which are then sent to the collection and storage device 18. The control system is connected to the pressure controller 202, the pressure boosting valve 203, and the voltage generator 710 via the electromagnetic controller 11 and control signal line 10 to coordinate the adjustment of pressure and electric field parameters.

[0044] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A separation and purification system enhanced by multi-field coupling, characterized in that: The system includes a vacuum pump, at least one cryogenic cyclone separator, at least one electric field-enhanced molecular distillation apparatus, and a control system. The vacuum pump is connected to both the cryogenic cyclone separator and the electric field-enhanced molecular distillation apparatus, providing a vacuum environment for both. The gas-phase enriched stream outlet of the cryogenic cyclone separator is fluidly connected to the liquid inlet pipe of the electric field-enhanced molecular distillation apparatus, allowing the enriched stream obtained from the cryogenic cyclone separation to serve as the feed for the electric field-enhanced molecular distillation, thus forming at least one stage of coupled purification path of cryogenic cyclone pre-separation and electric field-enhanced molecular distillation. The cryogenic cyclone separator includes a cyclone separator and a cavity formed by the inner and outer cylinders of the cryogenic cyclone separator, and is equipped with a gas collecting hood, a distributor, a vaporization pipe, a liquid inlet / outlet valve, and a discharge valve. The gas collecting hood is used to collect and discharge the gas-phase enriched stream, and the discharge valve is used to... The residual liquid is discharged, and the liquid inlet and outlet valves are used to discharge the liquid phase stream. Therefore, the cryogenic cyclone separator is equipped with a gas phase enrichment stream outlet and a residual liquid outlet, and optionally a liquid phase outlet to achieve pre-separation and load distribution. The electric field enhanced molecular distillation device includes an outer cylinder and an inner cylinder, an inlet pipe and an inlet valve, a brushing structure for forming and renewing the liquid film on the surface of the inner cylinder, and an electric field application structure composed of a voltage generator, an electrode ring and a collecting electrode grid, and a collecting funnel for collecting the distillate. The voltage generator is used to form an electric field in the distillation space, so that different components obtain differentiated effects based on differences in charge characteristics or electrical response, thereby enhancing the liquid film mass transfer process and vapor and molecular migration process and improving separation selectivity.

2. The multi-field coupling enhanced separation and purification system according to claim 1, characterized in that: It includes at least two sets of cryogenic cyclone separators and at least two sets of electric field enhanced molecular distillation devices. Each set of devices is connected in series to form at least two stages of the coupled purification path. The output end of the purified product of the previous stage electric field enhanced molecular distillation device is fluidly connected to the feed end of the next stage cryogenic cyclone separator to achieve multi-stage purification. The pressure between adjacent stages is matched by a vacuum regulating valve, a pressure controller, a pressure boosting valve and a pressure boosting pipe to keep the purified product of the previous stage in a stable flow state when it is transported to the next stage and to reduce the risk of flash evaporation or entrainment. The number of stages in the multi-stage series can be set to two, three or four stages according to the target purity and raw material composition to achieve step-by-step load distribution and step-by-step purification.

3. The multi-field coupling enhanced separation and purification system according to claim 1, characterized in that: The cryogenic cyclone separator also includes a cryogenic compression device, which works in conjunction with the cryogenic cyclone separator to provide cryogenic conditions. The inner cylinder and outer cylinder of the cryogenic cyclone separator form a double-layer cylinder structure to form a cryogenic cavity and reduce the impact of external heat leakage on the stability of the cyclone separation.

4. The multi-field coupling enhanced separation and purification system according to claim 1, characterized in that: The cryogenic cyclone separator also includes a flow divider, a gas collecting hood, and a vaporization tube. The gas collecting hood is located at the upper part of the cavity to collect and discharge the gas-enriched stream. The flow divider is located at the lower part to achieve gas-liquid phase separation. The vaporization tube is used to provide a controllable flow or heat exchange vaporization path for the vapor or volatile components generated during the separation process. The liquid inlet and outlet valves and the discharge valve are located at the lower part to discharge the liquid phase stream and residual liquid. Alternatively, the discharge valve is used to independently discharge the residual liquid. The liquid inlet and outlet valves are used to independently discharge the liquid phase stream, so that the gas-enriched stream, liquid phase stream, and residual liquid can be discharged separately and facilitate graded recovery or reflux treatment.

5. The multi-field coupling enhanced separation and purification system according to claim 1, characterized in that: The cryogenic cyclone separator also includes a vacuum regulating valve, a pressure controller, a booster valve, a vacuum valve, a vacuum gas delivery valve, and a booster pipe. The vacuum regulating valve, vacuum valve, and vacuum gas delivery valve work in conjunction with the vacuum pump to form and regulate the vacuum state required for separation. The pressure controller, booster valve, and booster pipe are used to control the pressure state to achieve pressure matching and stable delivery during the feeding, enrichment flow output, and residual liquid discharge processes. The vacuum regulating valve is used to regulate the vacuum level of the separation chamber, the vacuum valve is used for start-up and shutdown isolation, and the vacuum gas delivery valve is used for gas extraction or replacement channel control to improve the stability of the system start-up and shutdown processes. Alternatively, the pressure controller and booster valve work together to control the delivery pressure difference between the cryogenic cyclone separator and the electric field enhanced molecular distillation device to reduce the impact of delivery fluctuations on the formation of the distillate film.

6. The multi-field coupling enhanced separation and purification system according to claim 1, characterized in that: The cryogenic cyclone separator also includes an electromagnetic stirrer, which works in conjunction with the cyclone separator to form a cyclone field. The electromagnetic stirrer's operating state is regulated by a control system to make the cyclone intensity controllable, adapting to the pre-separation requirements of different material systems and improving the stability of the enriched flow. The cyclone separator includes a rotating shaft with a magnetic core, cyclone blades, a cyclone separator housing, and a limiting support. The cyclone blades are mounted on the rotating shaft with the magnetic core to form a cyclone drive structure, and the limiting support is used to position and limit the rotating shaft. The rotating shaft with the magnetic core forms a magnetic coupling transmission with an external drive to achieve cyclone drive under sealed conditions, thereby reducing the risk of leakage and improving reliability in a cryogenic vacuum environment.

7. The multi-field coupling enhanced separation and purification system according to claim 1, characterized in that: electric field The enhanced molecular distillation apparatus also includes an outer cylinder vacuum valve and a sealing ring. The outer cylinder vacuum valve connects the outer cylinder of the enhanced molecular distillation apparatus to the vacuum pump to create a distillation vacuum environment, reducing the impact of non-condensable gases on distillation efficiency and the stability of the electric field. The sealing ring ensures a tight seal between the outer and inner cylinders of the enhanced molecular distillation apparatus. The brushing structure includes a magnetic stirrer base, a spiral support, a magnetic core rotor, a brushing disc, a brushing support rod, and a brushing head. The magnetic core rotor, located on the magnetic stirrer base, engages with an external drive to rotate the brushing disc, allowing the brushing support rod and brushing head to support the brushing disc. The device employs a system to brush, renew, and agitate the liquid film on the surface of the inner cylinder of the electric field-enhanced molecular distillation apparatus to form and maintain the liquid film state. The electric field application structure also includes positive and negative electrode wires. The electrode ring and collecting electrode mesh are electrically connected to the voltage generator via the positive and negative electrode wires to create an electric field in the distillation space. The collecting electrode mesh, in conjunction with a collecting funnel, collects the distillate and exports the purified product through a purified gas-liquid delivery valve. The electric field-enhanced molecular distillation apparatus also includes a residual liquid delivery valve for exporting residual liquid and a vent valve for venting. The electric field parameters output by the voltage generator can be adjusted by the control system to adapt to different material systems and target separation selectivity requirements. The multi-component materials to be separated can be any one or more of the following: cryogenic media and their mixtures, rare gases and their liquefied mixtures, or organic small molecule mixtures.

8. A separation and purification method enhanced by multi-field coupling, characterized in that... The steps are as follows: The first step is to start the vacuum pump to put the cryogenic cyclone separator and the electric field enhanced molecular distillation device into a vacuum environment. The vacuum state required for separation is adjusted by the vacuum degree regulating valve, vacuum valve and vacuum gas supply valve of the cryogenic cyclone separator, and the vacuum state required for distillation is adjusted by the vacuum valve of the outer cylinder of the electric field enhanced molecular distillation device. The second step involves starting the cryogenic compression unit to provide cryogenic conditions to the cryogenic cyclone separator. The multi-component materials to be separated are fed into the cryogenic cyclone separator, where pre-separation is achieved under the action of the cyclone field formed by the electromagnetic stirrer and the cryogenic conditions. The gas phase enrichment stream is discharged through the gas collection hood, while the liquid phase stream and residual liquid are discharged through the liquid inlet and outlet valves. The pressure is controlled by the pressure controller, pressure boosting valve and pressure boosting pipe. The third step is to open the liquid inlet valve so that the gas-phase enriched stream (or the enriched stream formed by conversion and collection) enters the electric field enhanced molecular distillation device through the liquid inlet pipe and forms a liquid film on the surface of the inner cylinder of the electric field enhanced molecular distillation device; the magnetic stirrer base is started in conjunction with the magnetic core rotor to drive the liquid brushing disc, liquid brushing support rod and liquid brushing head to brush, update and disturb the liquid film in order to carry out molecular distillation. The fourth step is to start the voltage generator and apply voltage to the electrode ring and the collecting electrode grid through the positive and negative electrode wires to form an electric field in the distillation space. This allows different components to achieve differentiated effects based on their charge characteristics or differences in electrical response, thereby simultaneously enhancing the liquid film mass transfer process and the vapor or molecular migration process and improving separation selectivity. The fifth step involves collecting the distillate obtained from the distillation at the collecting electrode mesh and collecting funnel, and then exporting it as a purified product through the purified gas-liquid delivery valve. Simultaneously, residual liquid is exported through the residual liquid delivery valve, and vented through the vent valve when necessary. Steps S2-S5 constitute a coupled purification step of cryogenic cyclone pre-separation-electric field-enhanced molecular distillation, and this coupled purification step is performed at least once. When the device contains at least two stages of coupled purification paths, the purified product exported from the previous stage of electric field-enhanced molecular distillation is sent to the next stage of cryogenic cyclone separation to repeat the coupled purification step, thereby achieving multi-stage purification. The control system is connected to the pressure controller, pressure boosting valve, and voltage generator of the cryogenic cyclone separation device via an electromagnetic controller and control signal lines to coordinate the adjustment of pressure and electric field parameters.

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