Washing device for production of lithium bis (fluorosulfonyl) imide
The washing device, which combines a hydrocyclone and a washing tower, solves the problem that stirred tank equipment cannot meet the requirements for continuous production of lithium bis(fluorosulfonyl)imide, achieving an efficient and stable production process, reducing costs and improving product quality.
Patent Information
- Application Number
- CN202520459761.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-17
- Publication Date
- 2026-02-24
- Estimated Expiration
- 2035-03-17
AI Technical Summary
Existing stirred tank equipment is insufficient to meet the continuous production process requirements of lithium bisfluorosulfonyl imide, resulting in high production costs, unstable product quality, and large equipment investment.
The washing device, which combines a hydrocyclone and a washing tower, uses the hydrocyclone for solid-liquid separation. Combined with the design of an agitator and a sight glass, it achieves countercurrent washing. The optimized design of the internal pipe and overflow port ensures that the material is thoroughly washed, and the corrosion resistance is improved by using PTFE-lined steel.
It enables continuous production of lithium bisfluorosulfonylimide, improves production efficiency and product quality stability, reduces production costs, and is suitable for large-scale production.
Smart Images
Figure CN223932120U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of chemical equipment, specifically relating to a washing device for the production of lithium bis(fluorosulfonyl)imide. Background Technology
[0002] Lithium bis(fluorosulfonyl)imide is an important lithium salt widely used in various chemical synthesis fields. With the continuous development of the new energy vehicle industry, the market prospects for lithium bis(fluorosulfonyl)imide are very broad.
[0003] Lithium bis(fluorosulfonyl)imide, with the chemical formula F₂NO₄S₂.Li, is used as an additive in battery materials to improve energy density and cycle life, while also reducing internal resistance and enhancing rate performance. Therefore, the demand for lithium bis(fluorosulfonyl)imide is continuously increasing against the backdrop of the development of the new energy vehicle industry. In the production process, lithium carbonate is typically synthesized into crude salt, followed by a sulfoxide dehydration process. Currently, the industry widely uses stirred tanks for washing and impurity removal, but these tank-type equipment is difficult to meet the requirements of continuous production processes and large-scale operations. This results in high production costs, unstable product quality, and large equipment investment. Utility Model Content
[0004] To address the above technical problems, the purpose of this utility model is to provide a washing device for the production of lithium bis(fluorosulfonyl)imide, which can achieve continuous production operation, thereby greatly improving production efficiency, enhancing product quality stability, enabling large-scale production of the product, and significantly reducing production costs.
[0005] To achieve the above technical objectives, this patent adopts the following technical solution:
[0006] A washing apparatus for the production of lithium bis(fluorosulfonyl)imide includes a hydrocyclone and a washing tower. The hydrocyclone is located at the top of the washing tower, and the top of the washing tower is provided with an inner extension pipe. The top end of the inner extension pipe extends out of the washing tower and connects to the lower outlet of the hydrocyclone. The washing tower body is provided with several paired agitators and sight glasses from top to bottom. Each pair of agitators and sight glasses is located at the same horizontal position and is respectively arranged on opposite sides of the washing tower. The washing tower body is provided with a washing liquid inlet at the bottom, an overflow port at the top, a material outlet at the bottom, and a support frame on the washing tower body.
[0007] Furthermore, the washing tower body is divided into six sections from top to bottom, with adjacent sections connected by flanges. The inner extension pipe is located in the first section, and the overflow port is located at the upper part of the first section. The outlet of the inner extension pipe is lower than the overflow port to prevent the mixed liquid from being discharged directly from the overflow port without being fully washed. There are four agitators and four sight glasses, respectively located in the second, third, fourth, and fifth sections. The washing liquid inlet is located at the lower part of the fifth section. The upper part of the sixth section is cylindrical, and the lower part is conical. The cone angle γ of the cone is 50°~70°, and the bottom of the cone is provided with a material outlet.
[0008] Furthermore, the angle α between the sight glass and the washing tower body is 40°~50°, and the angle β between the agitator and the washing tower body is 55°~65°.
[0009] Furthermore, the agitator is a shielded agitator, with the agitator shaft extending into the washing tower, and the end of the agitator shaft equipped with blades located at the center of the washing tower.
[0010] Furthermore, the hydrocyclone and scrubbing tower, the inner pipe, the agitator shaft and blades are all made of steel lined with PTFE.
[0011] Due to the corrosive nature of the materials, this invention utilizes a steel-lined PTFE material. Starting with the mixture obtained after the synthesis of lithium difluorosulfonylimide crude salt and dehydration via sulfoxide, the mixture enters a hydrocyclone for solid-liquid separation. The slurry enters through an internal pipe at the top of the washing tower, with the outlet lower than the overflow port at the top of the tower to prevent the mixture from being discharged directly into the overflow port without sufficient washing. Four shielded agitators are installed in the tower body at a 60° angle, with the blades positioned at the center of the tower to thoroughly disperse the falling slurry. DCM washing liquid is introduced from the bottom of the washing tower to form countercurrent washing. The washed slurry is pumped out through the bottom of the tower to enter the next process. The washing liquid is discharged through the overflow port at the top of the washing tower for further treatment and recycling. A sight glass is installed in the tower body to observe the internal operation. Depending on actual production conditions, this device can be used in series or parallel. The tower body has other spare ports, which can be used to achieve internal circulation to improve the washing effect or to connect in series or parallel via spare ports. The entire process enables continuous material production and is highly practical. Attached Figure Description
[0012] Figure 1 This is a schematic diagram of the structure of this utility model;
[0013] Figure 2 This is a schematic diagram of the structure of the second section of the washing tower body in this utility model;
[0014] Figure 3 This is a schematic diagram of the sixth section of the washing tower body in this utility model;
[0015] In the diagram, 1. Hydrocyclone, 2. Scrubber, 21. Overflow port, 22. Internal pipe, 23. Washing liquid inlet, 24. Material outlet, 3. Sight glass, 4. Agitator, 5. Support frame. Detailed Implementation
[0016] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings.
[0017] A washing apparatus for the production of lithium difluorosulfonylimide, such as Figures 1 to 3 As shown, the washing tower includes a hydrocyclone 1 and a washing tower 2. The hydrocyclone 1 is located at the top of the washing tower 2. The top of the washing tower 2 is provided with an inner extension pipe 22. The top end of the inner extension pipe 22 extends out of the washing tower 2 and connects to the lower outlet of the hydrocyclone 1. The washing tower 2 has several paired agitators 4 and sight glasses 3 from top to bottom. Each pair of agitators 4 and sight glasses 3 is located at the same horizontal position and is respectively set on opposite sides of the washing tower 2 so as to facilitate observation of the agitator 4's agitation through the sight glasses 3. The washing tower 2 has a washing liquid inlet 23 at the bottom and an overflow port 21 at the top. The washing tower 2 has a material outlet 24 at the bottom and a support frame 5 on the washing tower 2.
[0018] The washing tower 3 is divided into six sections from top to bottom, with adjacent sections connected by flanges. The inner pipe 22 is located in the first section, and the overflow port 21 is located at the top of the first section. The outlet of the inner pipe 22 is lower than the overflow port 21 to prevent the mixed liquid from being discharged directly from the overflow port 21 without being fully washed. There are four agitators 4 and four sight glasses 3, which are respectively set in the second, third, fourth and fifth sections. The washing liquid inlet 23 is located at the bottom of the fifth section. The upper part of the sixth section is cylindrical and the lower part is conical. The cone angle γ of the cone is 60°, and the bottom of the cone is provided with a material outlet 24.
[0019] The angle α between the sight glass 3 and the body of the washing tower 2 is 45°, and the angle β between the agitator 4 and the body of the washing tower 2 is 60°.
[0020] The agitator 4 is a shielded agitator. The agitator shaft extends into the washing tower 2, and the end of the agitator shaft is equipped with blades, which are located at the center of the washing tower 3.
[0021] The hydrocyclone 1, the washing tower 2, the inner pipe 22, the stirring shaft and the blades of the agitator 4 are all made of steel lined with PTFE.
[0022] In use, during the production of lithium difluorosulfonylimide, lithium difluorosulfonylimide crude salt is synthesized from lithium carbonate. After adding excess sulfoxide for dehydration, the mixture enters the hydrocyclone 1 of this unit for solid-liquid separation. The slurry enters through the inner extension pipe 22 at the top of the washing tower, and DCM washing liquid is introduced from the washing liquid inlet 23 at the bottom of the washing tower 2 to form countercurrent washing. During the descent of the slurry, it is fully dispersed by the stirring blades to improve the washing effect. The washed slurry is pumped out from the bottom of the tower to the next process; the washing liquid is discharged from the overflow port 21 at the top of the tower for further treatment and recycling.
[0023] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A washing apparatus for the production of lithium difluorosulfonylimide, characterized in that, The system includes a hydrocyclone and a washing tower. The hydrocyclone is located at the top of the washing tower, and the top of the washing tower has an internal extension pipe. The top end of the internal extension pipe extends out of the washing tower and connects to the lower outlet of the hydrocyclone. The washing tower body has several paired agitators and sight glasses from top to bottom. Each pair of agitators and sight glasses is located at the same horizontal position and is respectively set on opposite sides of the washing tower. The washing liquid inlet is located at the bottom of the washing tower body, the overflow port is located at the top of the washing tower body, the material outlet is located at the bottom of the washing tower body, and the support frame is located on the washing tower body.
2. The washing apparatus for the production of lithium bis(fluorosulfonyl)imide according to claim 1, characterized in that, The washing tower is divided into six sections from top to bottom. Adjacent sections are connected by flanges. The inner pipe is located in the first section, and the overflow port is located at the top of the first section. The outlet of the inner pipe is lower than the overflow port. There are four agitators and four sight glasses, which are respectively set in the second, third, fourth, and fifth sections. The washing liquid inlet is located at the bottom of the fifth section. The upper part of the sixth section is cylindrical and the lower part is conical. The cone angle γ of the cone is 50°~70°. The bottom of the cone is provided with a material outlet.
3. The washing apparatus for the production of lithium bis(fluorosulfonyl)imide according to claim 1, characterized in that, The angle α between the sight glass and the washing tower body is 40°~50°, and the angle β between the agitator and the washing tower body is 55°~65°.
4. The washing apparatus for the production of lithium bis(fluorosulfonyl)imide according to any one of claims 1 to 3, characterized in that, The agitator is a shielded agitator, with its agitator shaft extending into the washing tower. The end of the agitator shaft is equipped with blades, which are located at the center of the washing tower.
5. The washing apparatus for the production of lithium bis(fluorosulfonyl)imide according to claim 4, characterized in that, The hydrocyclone and scrubbing tower, the inner pipe, the agitator shaft and blades are all made of steel lined with PTFE.