A high-purity ethylene carbonate crystallizer

Abstract

The utility model discloses a kind of ethylene carbonate high-purity crystallizers, it is related to ethylene carbonate processing technical field, the utility model includes low-temperature crystallizing tank, and low-temperature crystallizing tank bottom is connected with inner discharge gate and outer discharge gate respectively, and outer discharge gate outer surface is connected with sealing shell, servo motor cylinder is installed in sealing shell inside, and servo motor cylinder output end is connected with support, and support inside is installed with purging spray head. The utility model is through the setting of servo motor cylinder, support and purging spray head, servo motor cylinder can drive support axial displacement, and then drive purging spray head switch between inner discharge gate and outer discharge gate;When blockage trend appears in the upper portion inside inner discharge gate, purging spray head can enter the inside of inner discharge gate, and dry compressed nitrogen gas is sprayed by outside supply, and pulse airflow is effectively dredged, and solid ethylene carbonate is blocked in the upper portion and top of inner discharge gate;It is convenient to clear blockage, and nitrogen gas cannot react with ethylene carbonate, to avoid pollution.

Description

Technical Field

[0001] This utility model relates to the field of ethylene carbonate processing technology, specifically to a high-purity ethylene carbonate crystallizer. Background Technology

[0002] Ethylene carbonate is an important cyclic carbonate compound, a colorless and transparent liquid at room temperature, exhibiting good chemical stability and solubility. High-purity ethylene carbonate is widely used in lithium-ion battery electrolyte solvents, pharmaceutical intermediate synthesis, and fine chemical raw materials. Particularly in the lithium-ion battery industry, high-purity ethylene carbonate directly affects the ionic conductivity of the electrolyte and battery performance; therefore, achieving its high-purity preparation is one of the core requirements in related processing fields.

[0003] Ethylene carbonate is usually a transparent, colorless liquid at temperatures above 35°C, which is also its state after distillation and condensation purification. When the temperature is below this value, it slowly solidifies into white crystals. To facilitate long-term storage and solid-state transportation, ethylene carbonate is usually crystallized in a low-temperature crystallizer, transforming from a liquid to a solid state. This is achieved by lowering the temperature of the ethylene carbonate in the crystallizer through a cooling jacket, while simultaneously stirring it continuously with a stirrer. This method does not require complex phase transitions and is currently the most economical and commonly used method for crystallizing ethylene carbonate.

[0004] The discharge structure of existing low-temperature crystallizers is mostly a single traditional pipe style. When solid ethylene carbonate is discharged from the discharge port, due to factors such as the friction between the solid material and the inner wall of the discharge port and the agglomeration of the material itself, blockage is easily formed inside the discharge port, causing production interruption and reducing production continuity. Manual intervention is required, which not only increases operating costs, but also may increase the risk of ethylene carbonate contamination due to external contact or improper handling, resulting in a certain amount of material waste. Summary of the Invention

[0005] Therefore, the purpose of this utility model is to provide a high-purity crystallizer for ethylene carbonate to solve the technical problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a high-purity ethylene carbonate crystallizer, comprising a low-temperature crystallizer, wherein an inner outlet and an outer outlet are respectively connected to the bottom of the low-temperature crystallizer, and a sealing shell is connected to the outer surface of the outer outlet; a servo electric cylinder is installed inside the sealing shell, and a bracket is connected to the output end of the servo electric cylinder; a purge nozzle is installed inside the bracket, and an intermediate pipe is connected to the bottom of the purge nozzle; an air inlet is fixed to the outer surface of the sealing shell, and a corrugated pipe is connected between the air inlet and the intermediate pipe.

[0007] By adopting the above technical solution, the servo electric cylinder can drive the bracket to move precisely along the axial direction, thereby driving the purging nozzle to switch between the inner discharge port and the outer discharge port. When the inner discharge port is blocked, the nozzle can move in and spray out a pulse airflow through the dry compressed nitrogen connected to the air inlet to clear the blockage. The nitrogen does not react with ethylene carbonate, avoiding pollution. The corrugated pipe can adaptively stretch or contract with the nozzle displacement, and the intermediate pipe can adapt the gas flow direction. The overall structure can replace manual clearing, solving the problem of easy blockage and need for manual intervention in existing single pipelines, ensuring production continuity, and reducing operating costs and pollution risks.

[0008] Furthermore, the inner discharge port is located inside the outer discharge port, and the length of the inner discharge port is less than the length of the outer discharge port. The inner discharge port is connected to the outer discharge port, and the diameter of the bottom of the inner discharge port is greater than the diameter of the top of the inner discharge port.

[0009] By adopting the above technical solution, the inner discharge port is nested inside the outer discharge port and remains connected. Its gradually changing structure, which is narrow at the top and wide at the bottom, can gradually expand the channel cross-section along the discharge direction of solid ethylene carbonate, significantly reducing the friction and extrusion between the solid material and the inner wall, and structurally reducing the probability of accumulation and blockage.

[0010] Furthermore, the bracket is slidably connected to the inner discharge port, and the back of the bracket is arc-shaped.

[0011] By adopting the above technical solution, the sliding of the bracket can drive the displacement of the purging nozzle, and the arc shape of the back matches the inner ring of the inner discharge port to form a complete circular channel.

[0012] Furthermore, the purging nozzle is detachably connected to the inner discharge port and the outer discharge port.

[0013] By adopting the above technical solution, when the purging nozzle is transferred to the inner discharge port, it can pulse-purge dry compressed nitrogen to clear the material blocked in the upper and top of the discharge port. When the purging nozzle is transferred to the outer discharge port, it can avoid occupying the middle of the inner discharge port and aggravating the risk of blockage.

[0014] Furthermore, the longitudinal section of the intermediate tube is L-shaped.

[0015] By adopting the above technical solution, the L-shaped longitudinal section structure of the intermediate tube can redirect the dry compressed nitrogen gas delivered from the bellows to the direction of the purging nozzle. This structure allows the bellows to only bear axial tensile or contractile forces, without having to bear radial bending deformation, thus extending the service life of the bellows.

[0016] Furthermore, the top of the low-temperature crystallizer is connected to a feed inlet and a stirrer, and a cooling jacket is fitted around the outside of the low-temperature crystallizer.

[0017] By adopting the above technical solution, the feed inlet provides a convenient feeding channel for the liquid ethylene carbonate to be crystallized; the cooling jacket can stably control the temperature inside the tank, reducing the temperature of the liquid ethylene carbonate inside the tank below the freezing point to meet the requirements of the crystallization phase change; the stirrer can continuously operate during the crystallization process, breaking the temperature gradient and concentration gradient inside the tank, avoiding uneven crystallization particles caused by local supercooling, ensuring the uniformity of the temperature and concentration of the materials inside the tank, and finally forming solid ethylene carbonate with uniform particles and qualified purity.

[0018] Further, a limit switch is installed inside the outer discharge port, and the purging nozzle abuts against the limit switch.

[0019] By adopting the above technical solution, it can effectively avoid the partial retention of the nozzle inside the inner discharge port due to the stroke deviation of the servo electric cylinder; if the nozzle is retained, it will occupy the space of the inner discharge port and increase the risk of blockage when discharging subsequent materials, while the positioning function of the limit switch can completely avoid this problem, ensuring the unobstructed passage of the inner discharge port and ensuring smooth material discharge.

[0020] Further, the cross-section of the bracket is in the shape of a "square", and the longitudinal section of the bracket is in the shape of a "T".

[0021] By adopting the above technical solution, the combination of the two cross-sectional shapes makes the overall structure of the bracket compact, and it will not overly block the material channels of the inner discharge port or the outer discharge port, which not only meets the installation requirements of the blockage clearing components but also does not affect the normal discharge efficiency of solid ethylene carbonate.

[0022] Further, the bracket, the purging nozzle, the bellows and the intermediate pipe are all made of 316L stainless steel material.

[0023] By adopting the above technical solution, 316L stainless steel has excellent corrosion resistance, low-temperature tolerance and cleanliness; it is not easy to react with solid ethylene carbonate and mother liquor, avoiding component corrosion and material contamination.

[0024] Further, both the inner discharge port and the outer discharge port are fixedly connected to the bottom of the low-temperature crystallization tank by welding.

[0025] By adopting the above technical solution, the welding fixing method can make the inner discharge port, the outer discharge port and the bottom of the low-temperature crystallization tank form an integrated structure, avoiding the possible gaps or looseness of the traditional bolt connection; on the one hand, it can prevent the mother liquor inside the tank from leaking from the connection part during the crystallization process, reducing material waste and potential production safety hazards; on the other hand, it can isolate external air, dust and other impurities from entering the tank or the discharge port through the connection gap, ensuring the cleanliness of the materials; at the same time, the welding structure has stronger bearing capacity, can withstand the impact and pressure during long-term material discharge, avoid the deformation or detachment of the discharge port due to stress, ensure the long-term stable operation of the equipment, and reduce the maintenance cost.

[0026] In summary, the present invention has the following main advantages: 1. This utility model, through the arrangement of a servo electric cylinder, a bracket, and a purging nozzle, allows the servo electric cylinder to drive the bracket to move axially, thereby causing the purging nozzle to switch between the inner and outer discharge ports. When a blockage occurs at the top of the inner discharge port, the purging nozzle can enter the inner discharge port and spray a pulsed airflow using externally supplied dry compressed nitrogen, effectively clearing the solid ethylene carbonate blockage above and at the top of the inner discharge port. After clearing the blockage, the bracket can drive the purging nozzle to return to the inner discharge port, ensuring the inner discharge port is unobstructed and free of additional obstructions. This reduces the space occupied by the clearing structure within the inner discharge port, thus reducing the probability of blockage and minimizing the operational costs and product contamination risks associated with manual intervention in clearing blockages. Clearing blockages is convenient, and nitrogen does not react with ethylene carbonate, thus avoiding contamination. 2. This utility model, through the setting of an inner discharge port and an outer discharge port, has two advantages. Firstly, the bottom diameter of the inner discharge port is one centimeter or more larger than the top diameter, creating a gradually widening structure with a narrow top and wide bottom. This structure gradually expands the channel cross-section along the discharge direction of solid ethylene carbonate, significantly reducing friction and compression between the solid material and the inner wall of the inner discharge port, lowering the probability of material accumulation and blockage in the channel, and providing a structural basis for smooth material discharge. Secondly, when the support and the purging nozzle are reset, if a small amount of solid ethylene carbonate is carried on their surface, this material can naturally fall into the outer discharge port. Since the outer discharge port and the inner discharge port are connected, the fallen solid ethylene carbonate can enter the subsequent process along with the normally discharged material, reducing waste caused by material residue. The stacked structure of the two discharge ports reduces both blockage inside the inner discharge port and waste. 3. With the addition of a bellows and an intermediate tube, this utility model allows the bellows to adapt to the change in the distance between the nozzle and the air inlet by stretching or contracting itself when the purging nozzle moves with the support. An additional bellows compensator can also be added to guide the axial movement of the bellows. The L-shaped intermediate tube can change the flow direction of the dry compressed nitrogen, so that the bellows only needs to bear the axial stretching or contraction force and does not need to bear the radial bending deformation; making it convenient to use. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a cross-sectional structural diagram of the present invention; Figure 3 This is a side sectional view of the present invention. Figure 4 This is a schematic diagram of the side section structure of the material outlet of this utility model; Figure 5 This is a side sectional view of the inner discharge port structure of this utility model.

[0028] In the diagram: 1. Low-temperature crystallizer; 2. Feed inlet; 3. Agitator; 4. Cooling jacket; 5. Inner outlet; 6. Outer outlet; 7. Sealing shell; 8. Servo electric cylinder; 9. Support; 10. Purge nozzle; 11. Limit switch; 12. Corrugated pipe; 13. Intermediate pipe; 14. Air inlet. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0030] The embodiments of this utility model will be described below based on its overall structure. Example

[0031] A high-purity crystallizer for ethylene carbonate, such as Figures 2-5As shown, the system includes a low-temperature crystallization tank 1. The bottom of the low-temperature crystallization tank 1 is connected to an inner discharge port 5 and an outer discharge port 6. The inner discharge port 5 is located inside the outer discharge port 6, and its length is shorter than that of the outer discharge port 6. The inner discharge port 5 and the outer discharge port 6 are connected. The diameter of the bottom of the inner discharge port 5 is larger than the diameter of its top, and the bottom diameter is one centimeter or more larger than the top diameter. This gradual change in the structure of the inner discharge port 5 (narrow at the top and wide at the bottom) reduces friction and compression between the solid material and the inner wall of the inner discharge port 5, lowering the probability of material accumulation and blockage within the channel. Simultaneously, the inner discharge port 5 is located inside the outer discharge port 6, and the two are interconnected. The outer discharge port 6 not only... This provides a stable installation support foundation for subsequent unblocking components and can also catch materials that may overflow or scatter from the inner outlet 5 during material discharge, ensuring the integrity of material collection. A sealing shell 7 is connected to the outer surface of the outer outlet 6, with the sealing shell 7 maintaining a seal with the contact surface of the outer outlet 6. The cable of the servo cylinder 8 passes through the sealing shell 7 via a sealed through-chamber connector, reducing contamination or mother liquor leakage caused by the exchange of internal and external media. The servo cylinder 8 is installed inside the sealing shell 7, and a bracket 9 is connected to the output end of the servo cylinder 8. The bracket 9 is slidably connected to the inner outlet 5, and its back is arc-shaped. A purge nozzle 10 is installed inside the bracket 9, and the purge nozzle 10 is detachably connected to both the inner outlet 5 and the outer outlet 6. The output end of the servo cylinder 8 drives the bracket. 9 moves axially. Because the support 9 and the inner discharge port 5 maintain a sliding connection, the support 9 will drive the purge nozzle 10 installed inside it to move towards the inner discharge port 5. Finally, the purge nozzle 10 will be transferred from the inside of the outer discharge port 6 to the inside of the inner discharge port 5. After the purge nozzle 10 enters the inner discharge port 5, it sprays pulse-type dry compressed nitrogen gas. The pulse gas delivery is controlled by an external gas supply device. This clears the solid ethylene carbonate blockage above and at the top of the inner discharge port 5, causing the blockage material to resume flow and be discharged with the mother liquor. The bottom of the purge nozzle 10 is connected to an intermediate pipe 13. The longitudinal section of the intermediate pipe 13 is "L"-shaped. An air inlet 14 is fixed on the outer surface of the sealing shell 7. The air inlet 14 is connected to the intermediate pipe 13. A bellows 12 is provided. After nitrogen enters through the air inlet 14, it is transported through the bellows 12 to the intermediate pipe 13 connected to the bottom of the purge nozzle 10. The intermediate pipe 13 has an L-shaped longitudinal section, which can change the flow direction of the dry compressed nitrogen, allowing the nitrogen to enter the interior of the purge nozzle 10 smoothly. At the same time, this structure allows the bellows 12 to only bear axial tensile or contractile forces, without having to bear radial bending deformation. When the purge nozzle 10 moves with the support 9, the intermediate pipe 13 will move synchronously with the nozzle, thereby applying axial tension or pressure to the bellows 12. This allows the bellows 12 to adapt to the change in the distance between the purge nozzle 10 and the air inlet 14 through its own stretching or contraction. If necessary, an additional bellows compensator can be added to guide the axial movement of the bellows 12.

[0032] See Figures 1-3 , in the above embodiment, a feed inlet 2 and a stirrer 3 are respectively connected to the top of the low-temperature crystallization tank 1, and a cooling jacket 4 is sleeved outside the low-temperature crystallization tank 1. The high-purity liquid ethylene carbonate to be crystallized is introduced into the low-temperature crystallization tank 1 through the feed inlet 2 at the top. Subsequently, the cooling jacket 4 sleeved outside the low-temperature crystallization tank 1 is started, and the temperature inside the tank is regulated through the cooling jacket 4 to lower the temperature of the liquid ethylene carbonate inside the tank below the freezing point. At the same time, the stirrer 3 inside the tank is started, and the continuous operation of the stirrer 3 ensures that the temperature and concentration of the materials inside the tank are uniform, reduces the situation of local supercooling or uneven crystallization, and promotes the gradual solidification of the liquid ethylene carbonate to form high-purity solid ethylene carbonate. Finally, a mixture of solid ethylene carbonate and mother liquor is formed inside the tank, which is prepared for subsequent discharge. The outlet 6 is connected to the feed inlet 2 of the centrifuge through a screw conveyor or other conveying equipment. The mixture of solid ethylene carbonate and mother liquor is sent into the centrifuge through the conveying equipment, and solid ethylene carbonate is obtained through centrifugal solid-liquid separation. Embodiment

[0033] Based on the above Embodiment 1, in order to improve the structural reset accuracy, the following settings are made now.

[0034] Refer to Figure 4 and Figure 5 , in the above embodiment, a limit switch 11 is installed inside the outlet 6, and the purge spray head 10 abuts against the limit switch 11. During the displacement of the support 9, the limit switch 11 installed inside the outlet 6 can assist in determining the reset position of the support 9, ensuring that when the support 9 is pushed back to the target position, it can be aligned with the inner wall of the inner outlet 5, avoiding the situation that part of the area stays in the inner outlet 5 due to the position deviation of the support 9, which affects the normal discharge of solid ethylene carbonate. The cross-section of the support 9 is in the shape of a "square", and the longitudinal section of the support 9 is in the shape of a "T", which can prevent the support 9 from contacting the limit switch 11 in advance during the displacement process, preventing the limit switch 11 from being accidentally triggered and causing the purge spray head 10 to stay inside the inner outlet 5, thereby reducing the risk of channel blockage caused by the retention of the purge spray head 10. Embodiment

[0035] Based on the above Embodiment 1, in order to facilitate long-term use, the following settings are made now.

[0036] Refer to Figures 2-5In the above embodiments, the bracket 9, the purge nozzle 10, the corrugated pipe 12, and the intermediate pipe 13 are all made of 316L stainless steel. This material has good corrosion resistance and cleanliness, and can adapt to the contact environment between high-purity solid ethylene carbonate and mother liquor, reducing the possibility of parts being corroded or contaminated. The inner outlet 5 and the outer outlet 6 are fixedly connected to the bottom of the low-temperature crystallizer 1 by welding. This fixing method can enhance the structural stability of the connection between the two and the crystallizer, reduce the risk of structural detachment during long-term use, and reduce the probability of mother liquor leakage or external contamination due to aging of the sealing of the connection parts, thus ensuring the long-term stable operation of the equipment.

[0037] The implementation principle of this utility model is as follows: First, the high-purity liquid ethylene carbonate to be crystallized is introduced into the low-temperature crystallization tank 1 through the top feed port 2. Then, the cooling jacket 4 attached to the outside of the low-temperature crystallization tank 1 is activated. The temperature inside the tank is regulated by the cooling jacket 4, so that the temperature of the liquid ethylene carbonate inside the tank drops below the freezing point. At the same time, the agitator 3 inside the tank is activated. The continuous operation of the agitator 3 ensures that the temperature and concentration of the material inside the tank are uniform, reducing local supercooling or uneven crystallization, and promoting the gradual solidification of the liquid ethylene carbonate into high-purity solid ethylene carbonate. Finally, a mixture of solid ethylene carbonate and mother liquor is formed in the tank, which is prepared for subsequent discharge. The discharge port 6 is connected to the centrifuge feed port 2 through an auger conveyor or other conveying equipment. The mixture of solid ethylene carbonate and mother liquor is sent into the centrifuge through the conveying equipment, and solid ethylene carbonate is obtained through centrifugal solid-liquid separation. After crystallization, the solid ethylene carbonate and mother liquor mixture in the tank is naturally discharged through the inner outlet 5 at the bottom of the low-temperature crystallization tank 1. The bottom diameter of the inner outlet 5 is one centimeter or more larger than the top diameter of the inner outlet 5, that is, the inner outlet 5 has a gradually changing structure with a narrow top and a wide bottom. The channel cross-section that gradually expands along the material discharge direction can reduce the friction and compression between the solid material and the inner wall of the inner outlet 5, and reduce the probability of material accumulation and blockage in the channel. At the same time, the inner outlet 5 is located inside the outer outlet 6 and the two are connected to each other. The outer outlet 6 not only provides a stable installation support foundation for the subsequent unblocking components, but also can receive the material that may overflow or scatter from the inner outlet 5 during the material discharge process, ensuring the integrity of material collection. When blockage occurs at the top and bottom of the inner discharge port 5, the servo cylinder 8 installed inside the sealing shell 7 is activated via electrical signals such as an error report from the conveyor at the bottom of the discharge port or no feeding from the centrifuge, or by manual operation by staff through the external control cabinet. The sealing shell 7 maintains a seal with the outer discharge port 6, and the cable of the servo cylinder 8 passes through the sealing shell 7 via a sealed through-chamber connector, reducing contamination or mother liquor leakage caused by the exchange of internal and external media. The output end of the servo cylinder 8 drives the bracket 9 to move axially. Because the bracket 9 maintains a sliding connection with the inner discharge port 5, the bracket 9 will drive the purge nozzle 10 installed inside it to move towards the inner discharge port 5, ultimately transferring the purge nozzle 10 from inside the outer discharge port 6 to inside the inner discharge port 5. At this time, the nozzle is fixed to the outer surface of the sealing shell 7. The air inlet 14 is connected to external dry compressed nitrogen. After entering through the air inlet 14, the nitrogen is transported through the bellows 12 to the intermediate pipe 13 connected to the bottom of the purge nozzle 10. The intermediate pipe 13 has an L-shaped longitudinal section, which can change the flow direction of the dry compressed nitrogen, allowing the nitrogen to enter the interior of the purge nozzle 10 smoothly. At the same time, this structure allows the bellows 12 to only bear axial tensile or contractile force, without bearing radial bending deformation. When the purge nozzle 10 moves with the support 9, the intermediate pipe 13 will move synchronously with the nozzle, thereby applying axial tension or pressure to the bellows 12, so that the bellows 12 adapts to the change in the distance between the purge nozzle 10 and the air inlet 14 through its own stretching or contraction. If necessary, an additional bellows compensator can be added to guide the axial movement of the bellows 12. After the purge nozzle 10 enters the inner discharge port 5, it sprays pulsed dry compressed nitrogen gas. The pulsed gas delivery is controlled by an external gas supply device. This clears the solid ethylene carbonate blockage in the upper part and top of the inner discharge port 5, causing the blocked material to resume flow and be discharged with the mother liquor. After the blockage is cleared, the servo electric cylinder 8 drives the bracket 9 to move in its own direction, which drives the purge nozzle 10 to return from the inner discharge port 5 to the outer discharge port 6. This restores the inner discharge port 5 to a state of vertical connection, with no additional blockage clearing structure remaining to occupy channel space, further reducing the probability of blockage when subsequent materials are discharged. During the displacement of the support 9, the limit switch 11 installed inside the outlet 6 can help determine the reset position of the support 9, ensuring that the support 9 can be aligned with the inner wall of the inner outlet 5 when it is pushed back to the target position. This avoids some areas of the support 9 remaining in the inner outlet 5 due to positional deviation, which would affect the normal discharge of solid ethylene carbonate. At the same time, the structural design of the support 9, with a U-shaped cross section and a T-shaped longitudinal section, can prevent the support 9 from contacting the limit switch 11 prematurely during the displacement process. This prevents the limit switch 11 from being accidentally triggered, causing the purge nozzle 10 to remain inside the inner outlet 5, thereby reducing the risk of channel blockage caused by the purge nozzle 10 remaining inside. In addition, the support 9, the purge nozzle 10, the corrugated pipe 12, and the intermediate pipe 13 are all made of 316L stainless steel. This material has good corrosion resistance and cleanliness, and can adapt to the contact environment between high-purity solid ethylene carbonate and mother liquor, reducing the possibility of parts being corroded or contaminated. At the same time, the inner discharge port 5 and the outer discharge port 6 are fixedly connected to the bottom of the low-temperature crystallizer 1 by welding. This fixing method can enhance the structural stability of the connection between the two and the crystallizer, reduce the risk of structural detachment during long-term use, and reduce the probability of mother liquor leakage or external contamination due to aging of the connection seal, thus ensuring the long-term stable operation of the equipment.

[0038] Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the present invention and are not intended to limit the invention. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the present invention, provided that such modifications, substitutions, and variations are within the scope of the claims of the present invention and are protected by patent law.

Claims

1. A high-purity crystallizer for ethylene carbonate, comprising a low-temperature crystallization tank (1), characterized in that: The bottom of the low-temperature crystallization tank (1) is respectively connected with an inner discharge port (5) and an outer discharge port (6), and a sealing shell (7) is connected to the outer surface of the outer discharge port (6). A servo electric cylinder (8) is installed inside the sealing shell (7), and a bracket (9) is connected to the output end of the servo electric cylinder (8). A purge spray head (10) is installed inside the bracket (9), and an intermediate pipe (13) is connected to the bottom of the purge spray head (10). An air inlet interface (14) is fixed on the outer surface of the sealing shell (7), and a corrugated pipe (12) is connected between the air inlet interface (14) and the intermediate pipe (13).

2. The high-purity ethylene carbonate crystallizer according to claim 1, characterized in that: The inner discharge port (5) is located inside the outer discharge port (6), and the length of the inner discharge port (5) is less than the length of the outer discharge port (6). The inner discharge port (5) is communicated with the outer discharge port (6), and the diameter of the bottom of the inner discharge port (5) is larger than the diameter of the top of the inner discharge port (5).

3. The high-purity ethylene carbonate crystallizer according to claim 2, characterized in that: The bracket (9) is slidably connected to the inner discharge port (5), and the back of the bracket (9) is arc-shaped.

4. The high-purity ethylene carbonate crystallizer according to claim 2, characterized in that: The purge spray head (10) is detachably connected to the inner discharge port (5) and the outer discharge port (6).

5. The high-purity ethylene carbonate crystallizer according to claim 1, characterized in that: The longitudinal section of the intermediate pipe (13) is in an "L" shape.

6. The high-purity ethylene carbonate crystallizer according to claim 1, characterized in that: The top of the low-temperature crystallization tank (1) is respectively connected with a feed port (2) and a stirrer (3) is installed. A cooling jacket (4) is sleeved outside the low-temperature crystallization tank (1).

7. The high-purity ethylene carbonate crystallizer according to claim 1, characterized in that: A limit switch (11) is installed inside the outer discharge port (6), and the purge spray head (10) abuts against the limit switch (11).

8. The high-purity ethylene carbonate crystallizer according to claim 1, characterized in that: The cross-section of the bracket (9) is in a "square" shape, and the longitudinal section of the bracket (9) is in a "T" shape.

9. The high-purity ethylene carbonate crystallizer according to claim 1, characterized in that: The bracket (9), the purge spray head (10), the corrugated pipe (12) and the intermediate pipe (13) are all made of 316L stainless steel material.

10. The high-purity ethylene carbonate crystallizer according to claim 9, characterized in that: Both the inner discharge port (5) and the outer discharge port (6) are fixedly connected to the bottom of the low-temperature crystallization tank (1) by welding.

Images