Crystallization equipment and preparation system for lithium bis (fluorosulfonyl) imide

Abstract

The utility model discloses crystallization equipment. The crystallization equipment comprises a rotating shaft and a spiral blade, the spiral blade is arranged on the side wall of the rotating shaft and spirally extends in the axial direction of the rotating shaft, the spiral blade is provided with a cooling channel, a material channel and a heating channel, and the cooling channel, the material channel and the heating channel are sequentially arranged in the thickness direction of the spiral blade. And a plurality of liquid drainage holes are formed in one side, far away from the rotating shaft, of the spiral blade. Materials are firstly cooled through a cooling medium in the cooling channel, the materials are condensed into crystals, and the rotating shaft is rotated to discharge mother liquor through the liquid discharge hole. Then the materials are heated through a heating medium, after the temperature rises to a certain degree, the perspiration liquid is changed into a liquid state, the rotating shaft is rotated, the perspiration liquid is discharged through a liquid discharging hole, and refining of bis (fluorosulfonyl) imide is achieved. The utility model also discloses a preparation system for the lithium bis (fluorosulfonyl) imide.

Description

Technical Field

[0001] This application belongs to the field of chemical equipment technology, specifically relating to a crystallization device and a preparation system for lithium bis(fluorosulfonyl)imide. Background Technology

[0002] Lithium bisfluorosulfonylimide is a novel lithium salt with important applications in the lithium battery industry. Its synthesis mainly involves using aminosulfonic acid, chlorosulfonic acid, and thionyl chloride to prepare bisfluorosulfonylimide, which is then reacted with lithium salt to obtain lithium bisfluorosulfonylimide. As a key raw material in the synthesis of lithium bisfluorosulfonylimide, bisfluorosulfonylimide needs to be refined to improve product quality. Utility Model Content

[0003] Therefore, it is necessary to provide a crystallization apparatus capable of refining bis(fluorosulfonyl)imide by melt crystallization and a preparation system for lithium bis(fluorosulfonyl)imide.

[0004] The technical solution proposed in this application is as follows:

[0005] A crystallization apparatus, comprising:

[0006] Rotation axis;

[0007] A spiral blade is disposed on the side wall of the rotating shaft and extends spirally along the axial direction of the rotating shaft. The spiral blade has a cooling channel, a material channel and a heating channel. The cooling channel, the material channel and the heating channel are arranged sequentially in the thickness direction of the spiral blade and all extend along the extension direction of the spiral blade. The cooling channel is used for the flow of cooling medium and the heating channel is used for the flow of heating medium.

[0008] The spiral blade is provided with multiple drainage holes on the side away from the rotating shaft. The multiple drainage holes are arranged at intervals along the extension direction of the spiral blade and are connected to the material channel.

[0009] Using the crystallization equipment described above, liquid material (difluorosulfonyl imide) is fed into the material channel, and then cooled by the cooling medium in the cooling channel, causing the material to condense into crystals, while the mother liquor remains liquid. Next, the rotating shaft is rotated; during rotation, the mother liquor is discharged through the drain hole, while the crystals remain in the material channel, thus achieving solid-liquid separation. Next, the material is heated by a heating medium; after the temperature rises to a certain level, the material remains in a crystalline state, while the sap becomes liquid. Rotating the rotating shaft allows the sap to be discharged through the drain hole. In this way, both the mother liquor and the sap can be discharged from the material, achieving the purification of difluorosulfonyl imide. Furthermore, this crystallization equipment has a simple structure.

[0010] Furthermore, the crystallization device also includes a collection container, in which the rotating shaft and the spiral blades are both located, and the rotating shaft is rotatably configured.

[0011] Furthermore, the collection container is provided with a drain outlet and a discharge outlet, both of which are connected to the interior of the collection container.

[0012] Furthermore, the spiral blade includes a first end and a second end along its own extending direction. The first end has a feed inlet communicating with the material channel, and the end face of the second end has a discharge outlet communicating with the material channel.

[0013] The crystallization equipment also includes a feeding device, which is connected to the feed inlet.

[0014] Furthermore, the feed inlet is located on the side of the first end connected to the rotating shaft. The rotating shaft has an installation channel, which forms an opening at least at one end of the rotating shaft. The side wall of the rotating shaft has a first connection port communicating with the installation channel. The first connection port is connected to the feed inlet. The feeding device extends into the installation channel and communicates with the first connection port.

[0015] Furthermore, a first liquid inlet communicating with the cooling channel is provided on the side of the second end connected to the rotating shaft, and a first liquid outlet communicating with the cooling channel is provided on the side of the first end connected to the rotating shaft.

[0016] The side wall of the rotating shaft is also provided with a second connection port and a third connection port that communicate with the installation channel. The second connection port communicates with the first liquid inlet, and the third connection port communicates with the first liquid outlet.

[0017] The crystallization equipment also includes a cooling device, which extends into the installation channel and communicates with the second connection port and the third connection port.

[0018] Furthermore, a second liquid inlet communicating with the heating channel is provided on the side of the second end connected to the rotating shaft, and a second liquid outlet communicating with the heating channel is provided on the side of the first end connected to the rotating shaft.

[0019] The side wall of the rotating shaft is also provided with a fourth connection port and a fifth connection port that communicate with the installation channel. The fourth connection port communicates with the second liquid inlet and the fifth connection port communicates with the second liquid outlet.

[0020] The crystallization equipment also includes a heating device, which extends into the installation channel and communicates with the fourth connection port and the fifth connection port.

[0021] Furthermore, the first end is located above the second end.

[0022] Furthermore, the crystallization apparatus also includes a material detector, which is disposed in the material channel to detect the material input into the material channel.

[0023] A system for preparing lithium bis(fluorosulfonyl)imide includes the crystallization apparatus described above. Attached Figure Description

[0024] The accompanying drawings are provided to further understand this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof.

[0025] Figure 1 This is a schematic diagram of the structure of a crystallization apparatus provided in one embodiment of this application.

[0026] Label Explanation:

[0027] 110. Rotating shaft; 120. Spiral blade; 121. Cooling channel; 122. Material channel; 123. Heating channel; 124. Drain hole; 125. First end. Detailed Implementation

[0028] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0029] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the equipment or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0030] On the one hand, this application provides a crystallization apparatus that can purify bis(fluorosulfonyl)imide by melt crystallization.

[0031] Please participate Figure 1In one embodiment, the crystallization apparatus includes a rotating shaft 110 and helical blades 120. The rotating shaft 110 is rotatably disposed, and the helical blades 120 are disposed on the sidewall of the rotating shaft 110 and extend helically along the axial direction of the rotating shaft 110, i.e. Figure 1 As shown.

[0032] Furthermore, the spiral blade 120 is provided with a cooling channel 121, a material channel 122, and a heating channel 123. The cooling channel 121, the material channel 122, and the heating channel 123 are arranged sequentially in the thickness direction of the spiral blade 120 and all extend along the extension direction of the spiral blade 120. The cooling channel 121 is used for the flow of cooling medium, and the heating channel 123 is used for the flow of heating medium, thereby realizing the cooling and heating of the material in the material channel 122 respectively.

[0033] The spiral blade 120 is provided with multiple drainage holes 124 on the side away from the rotating shaft 110. The multiple drainage holes 124 are arranged at intervals along the extension direction of the spiral blade 120 and are connected to the material channel 122.

[0034] Using the crystallization equipment described above, liquid material is fed into material channel 122, and then cooled by the cooling medium in cooling channel 121, causing difluorosulfonyl imide to condense into crystals, while the mother liquor remains liquid. Next, the rotating shaft 110 is rotated; during rotation, the mother liquor is discharged through drain hole 124, while the crystals remain in material channel 122, thus achieving solid-liquid separation. Next, the material is heated by a heating medium. After the temperature rises to a certain level, the difluorosulfonyl imide remains in a crystalline state, while the sweat becomes liquid. Rotating the rotating shaft 110 allows the sweat to be discharged through drain hole 124. In this way, both the mother liquor and the sweat can be discharged from the material, achieving purification of difluorosulfonyl imide. Furthermore, the crystallization equipment has a simple structure.

[0035] It should be explained that the mother liquor is the remaining solution that did not crystallize during the crystallization process, and it usually contains uncrystallized solutes, impurities, and some solvent; the sweating liquid is a small amount of liquid remaining in the crystallized product, which may be residual mother liquor or secondary liquid generated during the crystallization process, and also contains impurities. Therefore, to achieve the purification of difluorosulfonyl imide, the material needs to be crystallized first, while removing the mother liquor formed during the crystallization process. Next, the material is heated to a certain temperature to form a sweating liquid with good fluidity, thus facilitating its discharge through the drain hole 124.

[0036] It should be noted that when the rotating shaft 110 remains stationary, the liquid material will not be discharged through the drain hole 124; however, during the rotation of the rotating shaft 110, due to the poorer fluidity of the crystallized difluorosulfonamide compared to the mother liquor and the sweating liquid, the difluorosulfonamide is difficult to discharge from the drain hole 124. Furthermore, when the material is added to the material channel 122, the rotating shaft 110 remains stationary.

[0037] In one embodiment, the spiral blade 120 includes a first end 125 and a second end along its extending direction. The first end 125 has a feed inlet communicating with the material channel 122, and the end face of the second end has a discharge outlet communicating with the material channel 122. Material is added into the material channel 122 through the feed inlet, and the cooling medium in the cooling channel 121 cools the material, causing the difluorosulfonamide to cool and crystallize. Then, the rotating shaft 110 is rotated, causing the mother liquor to be discharged through the drain hole 124.

[0038] It can be determined that some of the mother liquor and sweating liquid can be discharged through the outlet. However, since the crystallized difluorosulfonamide has a significant obstruction to the mother liquor and sweating liquid in the material channel 122 far from the outlet, in order to ensure the discharge of the mother liquor and sweating liquid, a drain hole 124 is opened on the outside of the spiral blade 120, so that when the rotating shaft 110 rotates, the mother liquor and sweating liquid in the material channel 122 are discharged from the drain hole 124 under the action of centrifugal force.

[0039] Furthermore, the first end 125 is located above the second end, meaning the inlet is above and the outlet is below. When liquid material is added to the material channel 122 through the upper inlet, the material flows spirally from top to bottom. During the flow, the material generates secondary circulation, breaking the laminar boundary layer, resulting in a more uniform solute distribution. This avoids excessively high local saturation and explosive nucleation, facilitating the formation of mother liquor and sweating liquid, thereby improving the purity of difluorosulfonyl imide.

[0040] Furthermore, it should be noted that after the sweating liquid is discharged, the rotation of the rotating shaft 110 can be stopped, and the material in the material channel 122 can be heated again, causing the difluorosulfonamide to re-enter the liquid state and flow out from the outlet. Of course, after the difluorosulfonamide is reheated into a liquid state, the rotating shaft 110 can be rotated again to fling the difluorosulfonamide in the material channel 122 out through the outlet.

[0041] In one embodiment, the feed inlet is located on the side where the spiral blade 120 is connected to the rotating shaft 110; the rotating shaft 110 has an installation channel, which has an opening at least at one end of the rotating shaft 110, for example, the opening can be formed at the top or bottom end of the rotating shaft 110 as shown in the figure, or the opening can be formed at both ends of the rotating shaft 110, that is, it completely penetrates both ends of the rotating shaft 110; the side wall of the rotating shaft 110 has a first connection port communicating with the installation channel, and the first connection port is communicating with the feed inlet.

[0042] Furthermore, the crystallization equipment also includes a feeding device, which extends into the installation channel and communicates with the first connection port, thereby inputting liquid material into the material channel 122 through the first connection port. It should be noted that the feeding device can be connected to the first connection port through a rotary joint, so that it can both input material into the material channel 122 and remain connected to the rotating shaft 110 during rotation.

[0043] In other embodiments, the feeding device can be detachably connected to the first connection port. Specifically, a robotic arm that does not rotate with the rotating shaft 110 can be installed in the installation channel. The robotic arm is equipped with a vision mechanism, which works in conjunction with the robotic arm to detachably connect the feeding device to the first connection port. For example, if the part of the feeding device that extends into the installation channel is a pipe, the robotic arm can grasp the pipe and, with the assistance of the vision mechanism, connect the pipe to the first connection port. In addition, it should be noted that if the feeding device is detachably installed, to prevent the difluorosulfonamide, mother liquor, or sweating liquid in the material channel 122 from flowing into the installation channel, a valve can be installed at the first connection port. The valve is detachably connected to the feeding device and can also be used to close the first connection port after the material input is completed.

[0044] In one embodiment, a first liquid inlet communicating with the cooling channel 121 is provided on the side of the second end 125 connected to the rotating shaft 110, and a first liquid outlet communicating with the cooling channel 121 is also provided on the side of the first end 125 connected to the rotating shaft 110. A second connection port and a third connection port communicating with the installation channel are also provided on the side wall of the rotating shaft 110. The second connection port communicates with the first liquid inlet, and the third connection port communicates with the first liquid outlet.

[0045] Furthermore, the crystallization equipment also includes a cooling device. The cooling device extends into the installation channel and connects to the second and third connection ports, allowing cooling medium to be introduced into the cooling channel 121 through the second connection port. The cooling medium in the cooling channel 121 flows back to the cooling device through the third connection port, achieving a circulating flow of the cooling medium. Simultaneously, the liquid material flows from top to bottom, while the cooling medium flows from bottom to top, enabling gradual cooling of the material and improving the cooling effect.

[0046] It should be noted that, since the cooling medium in the cooling channel 121 needs to circulate, in the preferred embodiment, the part of the cooling device that extends into the installation channel is connected to the second connection port and the third connection port through a rotary joint to prevent the cooling medium from rotating with the rotating shaft 110.

[0047] In one embodiment, a second liquid inlet communicating with the heating channel 123 is provided on the side where the second end 125 is connected to the rotating shaft 110, and a second liquid outlet communicating with the heating channel 123 is provided on the side where the first end 125 is connected to the rotating shaft 110. A fourth connection port and a fifth connection port communicating with the installation channel are also provided on the side wall of the rotating shaft 110. The fourth connection port communicates with the second liquid inlet port, and the fifth connection port communicates with the second liquid outlet port.

[0048] Furthermore, the crystallization equipment also includes a heating device. The heating device extends into the installation channel and communicates with the fourth and fifth connection ports. A heating medium is input into the heating channel 123 through the fourth connection port, and the heating medium in the heating channel 123 flows back to the heating device through the fifth connection port, achieving a circulating flow of the heating medium. Similarly, the flow direction of the heating medium is opposite to the flow direction of the material, which can improve the heating effect.

[0049] Based on the above description, it can be determined that, in the preferred embodiment, the portion of the heating device extending into the mounting channel is also connected to the fourth and fifth connection ports via a rotary joint, to prevent the heating device from rotating with the rotating shaft 110. Additionally, Figure 1 The bottom of the central helical blade 120 is shown in cross-section to illustrate the cooling channel 121, the material channel 122, and the heating channel 123.

[0050] In one embodiment, the crystallization apparatus further includes a material detector disposed in the material channel 122 to detect the material entering the material channel 122. Thus, after the material detector detects the material, a cooling medium can be introduced into the cooling channel 121 to cool the material, thereby causing the bis(fluorosulfonyl)imide crystals within the material channel 122 to solidify.

[0051] It should be explained that there is a certain distance between the material detector and the discharge port. After the material detector detects the material, it cools the material to ensure that it crystallizes and solidifies as it approaches the discharge port, preventing it from flowing out directly. Simultaneously, during the subsequent sweating process, the sweating liquid has better fluidity than the crystalline state of difluorosulfonyl imide; therefore, the sweating liquid near the discharge port will flow out before the material. Alternatively, in other embodiments, a baffle can be installed to seal the discharge port, and a driving structure can be used to move the baffle, opening and closing the discharge port to prevent material from flowing out directly during the addition process.

[0052] In one embodiment, the crystallization apparatus further includes a temperature detector disposed in the material channel 122 for detecting the temperature of the material. Thus, the state of the material within the material channel 122 can be determined by temperature. For example, when sweating the material, it needs to be heated to a certain temperature to ensure the production of sweating fluid. However, since difluorosulfonamide is in a crystalline state, the temperature detector can be used to detect whether the material has been heated to that temperature.

[0053] In one embodiment, the crystallization apparatus further includes a collection container, in which the rotating shaft 110 and the spiral blades 120 are both located, and the rotating shaft 110 is rotatably configured. The rotating shaft 110 may be driven to rotate by a drive structure disposed within the collection container.

[0054] It should be noted that during operation, the collection container may need to be kept in a vacuum state. Therefore, in the above embodiment, the feeding device, cooling device and heating device are preferably connected to the corresponding connection port through a rotary joint. In addition, even if the feeding device and the first connection port can be separated, the connection and separation are automatically performed by the robot arm in the installation channel in conjunction with the vision mechanism, without the need to break the vacuum of the collection container and then operate, thereby avoiding affecting production efficiency.

[0055] Furthermore, the collection container is equipped with a drain port and a discharge port, both of which are connected to the interior of the collection container. The drain port is used to discharge the mother liquor and sweat, while the discharge port is used to discharge liquid materials.

[0056] It should be noted that both the liquid outlet and the material outlet are located at the bottom of the collection container. As mentioned above, liquid materials are discharged from the material channel 122 through the material outlet, and since liquid materials have a certain degree of fluidity, they can also be discharged from the material outlet. In addition, in a preferred embodiment, the liquid outlet and the material outlet are the same opening, which is equipped with a three-way valve or a four-way valve. The mother liquor, sweating liquid, and liquid materials are all discharged from this opening, and then the output is controlled by the three-way valve or the four-way valve to different processes.

[0057] To facilitate understanding of the technical solutions of this application, the process flow of the crystallization equipment in the above embodiments is described below:

[0058] First, liquid material is fed into material channel 122 via a feeding device. When the material detector detects the material, a cooling device feeds a cooling medium into cooling channel 121 to cool the material, causing the bis(fluorosulfonyl)imide in material channel 122 to crystallize. Next, the cooling device is stopped, and the rotating shaft 110 is rotated. The mother liquor in material channel 122 is discharged into a collection container through the drain port and outlet, and then discharged through the drain port at the bottom.

[0059] A heating medium is introduced into the heating channel 123 via a heating device. The heating medium heats the material in the material channel 122. Heating stops once the material reaches a certain temperature, at which point sweating is generated. Rotating the rotating shaft 110 causes the sweating to be discharged into a collection container through the lower outlet and drain hole 124, and then discharged through the bottom drain hole. Next, the heating device continues to heat the bis(fluorosulfonyl)imide in the material channel 122 until it completely liquefies and flows out of the outlet into the collection container, where it is then discharged and collected through the bottom drain hole.

[0060] Based on the aforementioned crystallization equipment, this application also provides a system for preparing lithium bis(fluorosulfonyl)imide, which includes the aforementioned crystallization equipment. Specifically, bis(fluorosulfonyl)imide is purified using the crystallization equipment, and then lithium bis(fluorosulfonyl)imide is prepared from the bis(fluorosulfonyl)imide. It should be noted that the method for preparing lithium bis(fluorosulfonyl)imide from bis(fluorosulfonyl)imide can employ existing technology, and will not be elaborated upon here.

[0061] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A crystallization apparatus, characterized in that, include: Rotation axis; A spiral blade is disposed on the side wall of the rotating shaft and extends spirally along the axial direction of the rotating shaft. The spiral blade has a cooling channel, a material channel and a heating channel. The cooling channel, the material channel and the heating channel are arranged sequentially in the thickness direction of the spiral blade and all extend along the extension direction of the spiral blade. The cooling channel is used for the flow of cooling medium and the heating channel is used for the flow of heating medium. The spiral blade is provided with multiple drainage holes on the side away from the rotating shaft. The multiple drainage holes are arranged at intervals along the extension direction of the spiral blade and are connected to the material channel.

2. The crystallization apparatus according to claim 1, characterized in that, It also includes a collection container, in which the rotating shaft and the spiral blades are both located, and the rotating shaft is rotatably arranged.

3. The crystallization apparatus according to claim 2, characterized in that, The collection container has a drain outlet and a discharge outlet, both of which are connected to the interior of the collection container.

4. The crystallization apparatus according to claim 1, characterized in that, The spiral blade has a first end and a second end along its extension direction. The first end has a feed inlet communicating with the material channel, and the end face of the second end has a discharge outlet communicating with the material channel. The crystallization equipment also includes a feeding device, which is connected to the feed inlet.

5. The crystallization apparatus according to claim 4, characterized in that, The feed inlet is located on the side of the first end connected to the rotating shaft. The rotating shaft has an installation channel, which forms an opening at least at one end of the rotating shaft. The side wall of the rotating shaft has a first connection port that communicates with the installation channel. The first connection port communicates with the feed inlet. The feeding device extends into the installation channel and communicates with the first connection port.

6. The crystallization apparatus according to claim 5, characterized in that, The second end is connected to the rotating shaft and a first liquid inlet communicating with the cooling channel is also provided on the side of the first end connected to the rotating shaft and a first liquid outlet communicating with the cooling channel is also provided on the side of the first end connected to the rotating shaft. The side wall of the rotating shaft is also provided with a second connection port and a third connection port that communicate with the installation channel. The second connection port communicates with the first liquid inlet, and the third connection port communicates with the first liquid outlet. The crystallization equipment also includes a cooling device, which extends into the installation channel and communicates with the second connection port and the third connection port.

7. The crystallization apparatus according to claim 5, characterized in that, The second end is connected to the rotating shaft and a second liquid inlet is also provided on the side that communicates with the heating channel; the first end is connected to the rotating shaft and a second liquid outlet is also provided on the side that communicates with the heating channel. The side wall of the rotating shaft is also provided with a fourth connection port and a fifth connection port that communicate with the installation channel. The fourth connection port communicates with the second liquid inlet and the fifth connection port communicates with the second liquid outlet. The crystallization equipment also includes a heating device, which extends into the installation channel and communicates with the fourth connection port and the fifth connection port.

8. The crystallization apparatus according to claim 4, characterized in that, The first end is located above the second end.

9. The crystallization apparatus according to claim 4, characterized in that, It also includes a material detector, which is disposed in the material channel to detect the material input into the material channel.

10. A system for preparing lithium bis(fluorosulfonyl)imide, characterized in that, Includes the crystallization apparatus according to any one of claims 1-9.

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