An apparatus for purification of alkali metals

Abstract

This invention discloses an alkali metal purification device, relating to the field of alkali metal purification technology, including a skid-mounted base and frame; a pretreatment and raw material module, a vacuum and distillation core module, and a control and auxiliary module installed on the skid-mounted base and frame; through the cooperation of a quick-opening sealing structure and metal or fluororubber sealing rings, reliable sealing of the storage tank is ensured in a high vacuum or inert gas environment, fundamentally eliminating the risk of alkali metals coming into contact with air and moisture, and significantly improving the safety of the equipment; by using a distillation reactor in conjunction with a vertical distillation pump or a circulating pump, and setting up a heat exchange pipeline group between the distillation reactor and the condensation collection tank, precise control of material circulation and temperature in the distillation process is achieved, enabling stable heating of alkali metals to their boiling point and efficient condensation and collection in a vacuum environment, while effectively retaining high-boiling-point impurities at the bottom of the reactor, thereby obtaining high-purity alkali metal products.

Description

Technical Field

[0001] This invention relates to the field of alkali metal purification technology, and more specifically to an alkali metal purification device. Background Technology

[0002] Alkali metals (such as sodium, potassium, and lithium) are highly chemically reactive and readily react violently with oxygen and water vapor in the air at room temperature, sometimes even causing combustion or explosion. Therefore, the purification process of alkali metals requires strict isolation from air and moisture, typically using inert gas protection or a high-vacuum environment. Currently, commonly used industrial methods for alkali metal purification include distillation and zone melting, with vacuum distillation being the mainstream technology due to its high purification efficiency and wide applicability.

[0003] In existing alkali metal vacuum distillation purification equipment, the crude alkali metal storage tank, distillation kettle, condensation collection tank, and vacuum system are usually arranged separately, with each unit connected on-site via pipelines. This decentralized layout has the following drawbacks: the equipment occupies a large area, on-site installation and commissioning are complex, and there are many sealing interfaces between the units, increasing the risk of leakage; the top interface design of the crude alkali metal storage tank is relatively simple, usually only equipped with a feed port and a vacuum interface, making it difficult to simultaneously meet the multiple functional requirements of sealing protection, inert gas replacement, online monitoring, and safe pressure relief; the pretreatment filtration unit is mostly a single-column structure, and once the filter column is blocked or the medium needs to be replaced, the machine must be shut down, affecting the continuity of the purification process; and the precision of temperature and pressure control during the distillation process is insufficient, which can easily lead to impurity volatilization or alkali metal splashing due to local overheating, affecting product purity and operational safety. Summary of the Invention

[0004] The purpose of this invention is to provide an alkali metal purification device to solve the problems of existing technologies, such as large equipment footprint, complex on-site installation and commissioning, and numerous sealing interfaces between units, which increases the risk of leakage; and the relatively simple top interface design of crude alkali metal storage tanks, which usually only have a feed port and a vacuum interface, making it difficult to simultaneously meet the multiple functional requirements of sealing protection, inert gas replacement, online monitoring and safe pressure relief.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an alkali metal purification device, comprising a skid-mounted base and a frame; a pretreatment and raw material module, a vacuum and distillation core module, and a control and auxiliary module installed on the skid-mounted base and the frame;

[0006] The pretreatment and raw material module includes a crude alkali metal storage tank and a pretreatment filter column. The crude alkali metal storage tank is used to store crude alkali metal raw materials, and the pretreatment filter column is connected to the crude alkali metal storage tank to remove impurities from the crude alkali metal.

[0007] The vacuum and distillation core module includes a distillation reactor, a vacuum unit, and a condensation collection tank. The distillation reactor is connected to the outlet of the pretreatment filter column and is used to perform vacuum distillation on the pretreated alkali metal. The vacuum unit is used to provide a vacuum environment for the system. The condensation collection tank is connected to the vapor outlet of the distillation reactor and is used to condense and collect high-purity alkali metal vapor.

[0008] The control and auxiliary module includes an operation control panel and an inert gas protection system. The operation control panel is connected to at least the pretreatment filter column and the distillation reactor and is used to monitor and control process parameters. The inert gas protection system is used to fill the system with inert gas.

[0009] Furthermore, there are two pretreatment filter columns, which are connected in parallel between the crude alkali metal storage tank and the distillation reactor.

[0010] Furthermore, the bottom and side of the crude alkali metal storage tank are branched off by two branch pipes through a horizontal main pipe, which are respectively connected to the bottom inlets of the two pretreatment filter columns; the top outlets of the two pretreatment filter columns are merged through a top manifold and then connected to the feed pipe of the distillation reactor.

[0011] Furthermore, the top of the crude alkali metal storage tank is equipped with a sealing structure, a material operation interface, an inert gas and vacuum system interface, and a maintenance manhole.

[0012] The sealing structure is a quick-opening sealing manhole with a flange cover. A metal gasket or fluororubber sealing ring is provided between the flange cover and the top of the crude alkali metal storage tank.

[0013] The material operation interface includes a feeding port, a sampling port, and a sensor mounting interface;

[0014] The inert gas and vacuum system interface is used to connect the inert gas protection system and the vacuum unit.

[0015] Furthermore, the distillation reactor is a small tank, which is equipped with a stirring device and a circulation pump connected to it via a pipeline; the outlet of the circulation pump is connected to the distillation pipeline.

[0016] Furthermore, the vacuum and distillation core module also includes a heat exchange pipeline assembly disposed between the distillation reactor and the condensation collection tank, for controlling the delivery and condensation temperature of alkali metal vapor.

[0017] Furthermore, a square instrument cover is installed on the top of the pretreatment filter column, which is used to monitor the pressure and temperature inside the column.

[0018] Furthermore, the control and auxiliary module also includes a utility main pipe installed within the skid base and frame. All material pipes, protective gas pipes, and vacuum pipes are laid along the skid base and frame and are centrally connected to the main inlet and outlet flange on the side of the equipment.

[0019] Furthermore, the crude alkali metal storage tank, the pretreatment filter column, the distillation reactor, and the condensation collection tank are all connected to the inert gas protection system via pipelines to perform inert gas replacement and purging before and after equipment use.

[0020] Furthermore, the top of the crude alkali metal storage tank is also integrated with a safety valve, or the top of the crude alkali metal storage tank is also integrated with a rupture disc, for automatically depressurizing when the pressure inside the tank rises abnormally.

[0021] Compared with existing technologies, the alkali metal purification equipment provided by this invention integrates the pretreatment and raw material module, the vacuum and distillation core module, and the control and auxiliary module onto the same skid-mounted base and frame. This modular and skid-mounted design results in a compact overall structure that is easy to move, install, and deploy on-site, significantly improving the equipment's integration and ease of operation. By setting two parallel pretreatment filter columns and forming a switchable filtration path between the crude alkali metal storage tank and the distillation reactor, the equipment can switch, backwash, or change the media without shutting down, ensuring the continuity and stability of the pretreatment process. Simultaneously, the filter columns effectively remove solid particles and oxides from the crude alkali metal, providing high-quality raw materials for subsequent distillation purification. In particular, the quick-opening sealing structure combined with metal or fluororubber sealing rings ensures that the storage tank operates under high vacuum or inert gas conditions. The reliable sealing under vacuum fundamentally eliminates the risk of alkali metals coming into contact with air and moisture, significantly improving equipment safety. By using the distillation reactor in conjunction with a vertical distillation pump or circulating pump, and installing a heat exchange pipeline assembly between the distillation reactor and the condensation collection tank, precise control of material circulation and temperature during the distillation process is achieved. This allows for stable heating of alkali metals to their boiling point and efficient condensation and collection in a vacuum environment, while effectively retaining high-boiling-point impurities at the bottom of the reactor, resulting in high-purity alkali metal products. By connecting the control panel to the measuring points of each functional module and uniformly arranging the main utility pipe, operators can monitor key process parameters such as temperature, pressure, and liquid level in real time and precisely control the distillation rate, avoiding product contamination caused by local overheating or impurity volatilization. Furthermore, the centralized connection of material pipes, protective gas pipes, and vacuum pipes simplifies external pipeline connections and reduces the risk of leakage. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0023] Figure 1 This is a schematic diagram of the overall structure of the alkali metal purification equipment provided in an embodiment of the present invention.

[0024] Explanation of reference numerals in the attached figures:

[0025] 100. Pretreatment and Raw Material Module; 101. Crude Alkali Metal Storage Tank; 102. Pretreatment Filter Column; 103. Pretreatment Control Valve Assembly; 200. Vacuum and Distillation Core Module; 201. Distillation Reactor; 202. Vacuum Unit; 203. Condensation Collection Tank; 300. Control and Auxiliary Module; 301. Operation Control Panel; 302. Inert Gas Protection System; 303. Skid-Mounted Base and Frame; 304. Heat Exchange Piping Assembly. Detailed Implementation

[0026] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0027] As attached Figure 1 As shown:

[0028] Example 1:

[0029] This invention provides an alkali metal purification device, comprising a skid-mounted base and frame 303; a pretreatment and raw material module 100, a vacuum and distillation core module 200, and a control and auxiliary module 300 mounted on the skid-mounted base and frame 303; the pretreatment and raw material module 100 includes a crude alkali metal storage tank 101 and a pretreatment filter column 102, the crude alkali metal storage tank 101 being used to store crude alkali metal raw materials, and the pretreatment filter column 102 being connected to the crude alkali metal storage tank 101 for removing impurities from the crude alkali metal; the vacuum and distillation core module 200 includes a distillation reactor 201, a vacuum unit 202, and a condensation collection tank 203. 03. The distillation reactor 201 is connected to the outlet of the pretreatment filter column 102 for vacuum distillation of the pretreated alkali metal. The vacuum unit 202 is used to provide a vacuum environment for the system. The condensation collection tank 203 is connected to the steam outlet of the distillation reactor 201 for condensing and collecting high-purity alkali metal vapor. The control and auxiliary module 300 includes an operation control panel 301 and an inert gas protection system 302. The operation control panel 301 is connected to at least the pretreatment filter column 102 and the distillation reactor 201 for monitoring and controlling process parameters. The inert gas protection system 302 is used to fill the system with inert gas.

[0030] The pretreatment filter column 102 consists of two columns, which are connected in parallel between the crude alkali metal storage tank 101 and the distillation reactor 201. The bottom and side of the crude alkali metal storage tank 101 are connected to two branch pipes through a horizontal main pipe, which are respectively connected to the bottom inlet of the two pretreatment filter columns 102. The top outlets of the two pretreatment filter columns 102 are connected to the feed pipe of the distillation reactor 201 after they are merged through a top manifold.

[0031] Furthermore, the top of the crude alkali metal storage tank 101 is equipped with a sealing structure, a material operation interface, an inert gas and vacuum system interface, and a maintenance manhole.

[0032] The sealing structure is a quick-opening sealing manhole with a flange cover. A metal gasket or fluororubber sealing ring is provided between the flange cover and the top of the crude alkali metal storage tank 101.

[0033] The material handling interface includes a feeding port, a sampling port, and a sensor mounting interface;

[0034] The inert gas and vacuum system interface is used to connect the inert gas protection system 302 and the vacuum unit 202;

[0035] It should be noted that the distillation reactor 201 is a small tank, which is equipped with a stirring device and a circulation pump connected to it via pipelines. The outlet of the circulation pump is connected to the distillation pipeline. The vacuum and distillation core module 200 also includes a heat exchange pipeline group 304 located between the distillation reactor 201 and the condensation collection tank 203, which is used to control the delivery and condensation temperature of alkali metal vapor.

[0036] Furthermore, a square instrument cover is installed on the top of the pretreatment filter column 102. The square instrument cover is used to monitor the pressure and temperature inside the column. The control and auxiliary module 300 also includes a utility main pipe set in the skid base and frame 303. Material pipes, protective gas pipes, and vacuum pipes are all laid along the skid base and frame 303 and are centrally connected to the main inlet and outlet flange on the side of the equipment.

[0037] Furthermore, the crude alkali metal storage tank 101, the pretreatment filter column 102, the distillation reactor 201, and the condensation collection tank 203 are all connected to the inert gas protection system 302 through pipelines to perform inert gas replacement and purging before and after equipment use.

[0038] The top of the crude alkali metal storage tank 101 is also equipped with a safety valve, or a rupture disc, for automatically releasing pressure when the pressure inside the tank rises abnormally.

[0039] The operator first checks the connections between the skid-mounted base and each module on the frame 303, confirming that all pipeline interfaces are properly sealed. The inert gas protection system 302 is activated, and high-purity argon gas is introduced into the crude alkali metal storage tank 101, the pretreatment filter column 102, and the distillation reactor 201. Simultaneously, the vacuum unit 202 is started to evacuate the system, repeating the evacuation and argon replacement three times to reduce the oxygen and moisture content inside the system to below 1 ppm. Then, under argon positive pressure protection, the crude potassium metal to be purified is added through the feed port at the top of the crude alkali metal storage tank 101. After feeding, the tank is completely sealed using a quick-opening sealing manhole and a metal gasket.

[0040] The heating temperature of the pretreatment filter column 102 is set to 120℃ via the control panel 301. The pretreatment control valve group 103 is opened, allowing crude potassium metal to flow out from the bottom of the crude alkali metal storage tank 101 and be diverted through the horizontal main pipe into the bottom inlets of the two parallel pretreatment filter columns 102. The crude potassium metal rises slowly within the filter column, where solid particles and oxides are effectively trapped by the filter medium. The purified alkali metal flows out from the top outlet of the filter column, is collected through the top manifold, and then transported to the upper inlet of the distillation reactor 201.

[0041] After all the crude potassium metal has been transferred to the distillation reactor 201, close the feed valve between the pretreatment and distillation modules. Turn on the heating system of the distillation reactor 201, and monitor the temperature inside the reactor in real time through the control panel 301. Under the condition that the system pressure is maintained below 10⁻³Pa by the vacuum unit 202, slowly raise the temperature to about 350℃, so that the potassium metal reaches its boiling point and begins to vaporize.

[0042] Simultaneously, the circulation pump connected to the bottom of the distillation reactor 201 is activated to circulate the liquid potassium metal within the reactor, ensuring uniform temperature distribution and preventing localized overheating. Potassium metal vapor enters the heat exchange pipeline assembly 304 through the vapor outlet at the top of the distillation reactor 201. While flowing through the heat exchange pipeline assembly 304, it is cooled by the cooling medium and then enters the condensation collection tank 203, where it condenses into liquid high-purity potassium metal. Throughout the distillation process, the operator monitors the temperature, pressure, and vapor flow parameters in real time via the control panel 301, dynamically adjusting the heating power and cooling medium flow rate based on the condensation collection rate to maintain a stable distillation rate. Impurities with boiling points higher than potassium metal remain at the bottom of the distillation reactor 201 because they cannot vaporize.

[0043] After distillation, shut off the heating system and keep the vacuum unit 202 running until the system cools to room temperature. Close the connecting valve between the distillation reactor 201 and the condensate collection tank 203, and fill the condensate collection tank 203 with argon gas to atmospheric pressure through the inert gas protection system 302. Under argon protection, the operator opens the sealing cap of the condensate collection tank 203, removes the high-purity potassium metal product, and vacuum seals it.

[0044] High-boiling-point impurities remaining in the distillation reactor 201 are discharged through the bottom discharge port and subjected to harmless treatment. Subsequently, argon gas is introduced into the crude alkali metal storage tank 101, pretreatment filter column 102, distillation reactor 201, and condensation collection tank 203 through the inert gas protection system 302 to purge residual alkali metal vapors and oxides from the pipelines and containers. After purging, the vacuum unit 202 and heating system are shut down, completing one full purification cycle.

[0045] During the entire operation, if the pressure inside the crude alkali metal storage tank 101 rises abnormally, the safety valve or rupture disc integrated at the top will automatically open to release pressure, ensuring the safety of equipment and personnel. If one of the pretreatment filter columns 102 becomes clogged, it can be switched to another filter column for independent operation through the pretreatment control valve group 103, achieving maintenance without shutting down the machine.

[0046] Example 2:

[0047] This embodiment is basically the same as the previous embodiment, except that the present invention also provides a method for using an alkali metal purification device.

[0048] S1: Preprocessing stage

[0049] S11: System Environment Setup

[0050] The vacuum unit 202 is started to evacuate the entire system, including the crude alkali metal storage tank 101, the pretreatment filter column 102, the distillation reactor 201, and the condensation collection tank 203. The system pressure is reduced to P0 ≤ 1×10⁻⁶. -3 At pressure Pa, high-purity argon gas is introduced into the system through the inert gas protection system 302 until atmospheric pressure is reached. This process of evacuation and purging is repeated three times to reduce the oxygen content C in the system. 氧 ≤ 0.5 ppm, moisture content C 水 ≤ 0.3 ppm.

[0051] S12: Crude Alkali Metal Loading

[0052] Under the protection of positive argon pressure, crude sodium metal is loaded through the feeding port at the top of crude alkali metal storage tank 101. After loading is completed, the tank is completely sealed with a quick-opening sealing manhole and a metal gasket. The tank is maintained at a slight positive pressure ΔP = 0.05~0.1MPa through the interface between inert gas and vacuum system.

[0053] S13: Pretreatment filtration

[0054] The heating temperature of the pretreatment filter column 102 is set to T1 = 120~150℃ by operating the control panel 301. The pretreatment control valve group 103 is opened, so that the crude sodium metal flows out from the bottom of the crude alkali metal storage tank 101 and is diverted into the bottom inlet of the two parallel pretreatment filter columns 102 through the horizontal main pipe. The crude sodium metal rises slowly in the filter column at a flow rate of v = 0.5~1.5m / h. The solid particles and oxides are intercepted by the filter medium. The purified alkali metal flows out from the top outlet of the filter column and is collected by the top manifold and transported to the upper inlet of the distillation reactor 201.

[0055] S2: Distillation and purification stage

[0056] S21: Establishment of the distillation environment

[0057] After all the crude sodium metal has been transferred to the distillation reactor 201, the feed valve between the pretreatment and distillation modules is closed, and the vacuum unit 202 is started to further reduce the system pressure to P1≤5×10. -4 Pa;

[0058] S22: Heating distillation

[0059] The heating system of the distillation reactor 201 is turned on, and the temperature inside the reactor is monitored in real time via the control panel 301. The temperature inside the reactor is raised to T2 = 400~420℃ at a heating rate k = 5~8℃ / min. Simultaneously, the circulation pump connected to the bottom of the distillation reactor 201 is started to circulate the liquid sodium metal inside the reactor, ensuring a temperature distribution uniformity coefficient η ≥ 0.95, where η is defined as...

[0060]

[0061] Where T max The highest temperature inside the vessel, T min The lowest temperature inside the vessel, T avg This represents the average temperature inside the vessel.

[0062] Sodium vapor enters the heat exchange pipeline group 304 through the steam outlet at the top of the distillation reactor 201. While flowing through the heat exchange pipeline group 304, it is cooled to T3 = 180~200℃ by the cooling medium, and then enters the condensation collection tank 203 to condense into liquid high-purity sodium.

[0063] S23: Distillation rate control

[0064] Throughout the distillation process, temperature, pressure, and steam flow parameters are monitored in real time via the control panel 301. Heating power and cooling medium flow are dynamically adjusted based on the condensation and collection rate to maintain a stable distillation rate, ensuring that the distillation rate R meets the required parameters.

[0065]

[0066] Where m is the mass of sodium metal collected, t is the distillation time, A is the condensation area of ​​the condensation collection tank 203, and R... max This is the critical distillation rate; exceeding this value will cause impurities to volatilize and enter the product.

[0067] S31: System Cooling

[0068] After distillation, turn off the heating system and keep the vacuum unit 202 running until the system cools down to room temperature T4≤40℃. At this time, confirm the pressure difference ΔP1 between the distillation reactor 201 and the condensation collection tank 203 is ≤0.01 MPa by operating the control panel 301.

[0069] S32: High-purity product collection

[0070] Close the connecting valve between the distillation reactor 201 and the condensation collection tank 203. Fill the condensation collection tank 203 with argon gas to atmospheric pressure through the inert gas protection system 302. Under argon protection, the operator opens the sealing cap of the condensation collection tank 203, removes the high-purity metallic sodium product, and vacuum seals it. Product purity... satisfy,

[0071]

[0072] in For high-purity metallic sodium, This represents the total mass of metallic sodium in the raw materials;

[0073] S33: Residual impurity treatment and system purging

[0074] High-boiling-point impurities remaining in the distillation reactor 201 are discharged through the bottom discharge port and subjected to harmless treatment. Subsequently, argon gas is purged through the inert gas protection system 302 into the crude alkali metal storage tank 101, the pretreatment filter column 102, the distillation reactor 201, and the condensate collection tank 203. The purging flow rate Q = 5~10 L / min, and the purging time t... p ≥ 30 min, to remove residual alkali metal vapors and oxides from pipelines and containers.

[0075] S4: Maintenance and Standby Phase

[0076] S41: Filter column maintenance

[0077] When the control panel 301 displays that the inlet and outlet pressure difference ΔP2 of one of the pretreatment filter columns 102 is greater than or equal to 0.2MPa, the pretreatment control valve group 103 switches to the other filter column to operate independently. At the same time, the clogged filter column is backwashed or the filter medium is replaced, so as to achieve maintenance without stopping the machine.

[0078] S42: Safety Relief Test

[0079] Monthly functional tests are performed on the safety valve or rupture disc at the top of the crude alkali metal storage tank 101 via the control panel 301 to ensure automatic pressure relief in case of abnormal pressure rise. The pressure relief threshold is set to P. max =0.3~0.5MPa;

[0080] Among them, the purity η of the alkali metal purified in the S13 pretreatment filtration step f Between the temperature uniformity coefficient η in the S22 heating distillation step and the pretreatment filter column 102 effectively removing oxide impurities from crude metallic sodium, the scaling rate on the inner wall of the distillation reactor 201 is significantly reduced, allowing the circulating pump to more effectively maintain temperature uniformity within the reactor. Specifically,

[0081]

[0082] Where η0 is the basic temperature uniformity coefficient, α is the influence coefficient of impurity removal on temperature uniformity, and η f The purity of alkali metals after pretreatment;

[0083] By using S13 pretreatment filtration, the temperature uniformity coefficient η during S22 distillation is improved from 0.85~0.90 in traditional equipment to over 0.95. This effectively avoids alkali metal splashing and volatilization of high-boiling-point impurities caused by localized overheating, resulting in higher product purity η. p The purity has been increased from 99.5% in traditional processes to over 99.95%.

[0084] Building upon this, the improvement in temperature uniformity further enhances the second layer of progressive effect in conjunction with the S23 distillation rate control step: due to the increase in the η value, the critical distillation rate R... max The distillation efficiency has been increased from 1.2 kg / (h·m²) in the traditional process to over 2.5 kg / (h·m²), meaning that the distillation efficiency has been increased by more than 100% while ensuring product purity. At the same time, the stable temperature distribution has reduced the control accuracy ΔR of the distillation rate on the control panel 301 from ±0.3 kg / (h·m²) in the traditional process to within ±0.1 kg / (h·m²), significantly enhancing the stability and repeatability of the process.

[0085] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An alkali metal purification device, characterized in that, include, Skid-mounted base and frame (303); pretreatment and raw material module (100), vacuum and distillation core module (200) and control and auxiliary module (300) mounted on the skid-mounted base and frame (303); The pretreatment and raw material module (100) includes a crude alkali metal storage tank (101) and a pretreatment filter column (102). The crude alkali metal storage tank (101) is used to store crude alkali metal raw materials. The pretreatment filter column (102) is connected to the crude alkali metal storage tank (101) and is used to remove impurities from the crude alkali metal. The vacuum and distillation core module (200) includes a distillation reactor (201), a vacuum unit (202), and a condensation collection tank (203). The distillation reactor (201) is connected to the outlet of the pretreatment filter column (102) for vacuum distillation of the pretreated alkali metal. The vacuum unit (202) is used to provide a vacuum environment for the system. The condensation collection tank (203) is connected to the steam outlet of the distillation reactor (201) for condensing and collecting high-purity alkali metal vapor. The control and auxiliary module (300) includes an operation control panel (301) and an inert gas protection system (302). The operation control panel (301) is connected to at least the pretreatment filter column (102) and the distillation reactor (201) and is used to monitor and control process parameters. The inert gas protection system (302) is used to fill the system with inert gas.

2. The alkali metal purification equipment according to claim 1, characterized in that, There are two pretreatment filter columns (102), which are connected in parallel between the crude alkali metal storage tank (101) and the distillation reactor (201).

3. The alkali metal purification equipment according to claim 2, characterized in that, The bottom and side of the crude alkali metal storage tank (101) are branched into two branches through a horizontal main pipe, which are respectively connected to the bottom inlets of the two pretreatment filter columns (102); the top outlets of the two pretreatment filter columns (102) are connected to the feed pipeline of the distillation reactor (201) after they are merged through a top manifold.

4. The alkali metal purification equipment according to claim 1, characterized in that, The top of the crude alkali metal storage tank (101) is equipped with a sealing structure, a material operation interface, an inert gas and vacuum system interface, and a maintenance manhole. The sealing structure is a quick-opening sealing manhole with a flange cover. A metal gasket or fluororubber sealing ring is provided between the flange cover and the top of the crude alkali metal storage tank (101). The material operation interface includes a feeding port, a sampling port, and a sensor mounting interface; The inert gas and vacuum system interface is used to connect the inert gas protection system (302) and the vacuum unit (202).

5. The alkali metal purification equipment according to claim 1, characterized in that, The distillation reactor (201) is a small tank, which is equipped with a stirring device and a circulation pump connected to it via a pipeline; the outlet of the circulation pump is connected to the distillation pipeline.

6. The alkali metal purification equipment according to claim 1, characterized in that, The vacuum and distillation core module (200) also includes a heat exchange pipeline group (304) disposed between the distillation reactor (201) and the condensation collection tank (203) for controlling the delivery and condensation temperature of alkali metal vapor.

7. The alkali metal purification equipment according to claim 1, characterized in that, The top of the pretreatment filter column (102) is equipped with a square instrument cover, which is used to monitor the pressure and temperature inside the column.

8. The alkali metal purification equipment according to claim 1, characterized in that, The control and auxiliary module (300) also includes a utility main pipe set in the skid base and frame (303). All material pipes, protective gas pipes and vacuum pipes are laid along the skid base and frame (303) and are centrally connected to the main inlet and outlet flange on the side of the equipment.

9. The alkali metal purification equipment according to claim 1, characterized in that, The crude alkali metal storage tank (101), the pretreatment filter column (102), the distillation reactor (201), and the condensation collection tank (203) are all connected to the inert gas protection system (302) through pipelines to replace and purge inert gas before and after the equipment is used.

10. An alkali metal purification device according to claim 1, characterized in that, The top of the crude alkali metal storage tank (101) is also equipped with a safety valve, or the top of the crude alkali metal storage tank (101) is also equipped with a rupture disc, which is used to automatically release pressure when the pressure inside the tank rises abnormally.

Images