A cooling and purification device and a cooling and purification system for isocyanate carbonylation intermediates

Abstract

The application provides a cooling and purifying device and system for isocyanate carbonylation intermediates, the cooling and purifying device comprises a cylinder body, the bottom of the cylinder body is a conical structure, a liquid outlet is arranged close to the tip of the conical structure, the cylinder body is sequentially divided into a spray granulation zone and a liquid phase washing zone along the material flow direction; the spray granulation zone comprises a granulation system and a cooling system which are sequentially arranged along the material flow direction; the liquid phase washing zone comprises a stirring system and a ventilation member which are sequentially arranged along the material flow direction, and the ventilation member is arranged in the conical structure and close to the liquid outlet. Through the specific design of the spray granulation zone and the liquid phase washing zone, the method of combining spray granulation, spray cooling and liquid phase washing of suspended particles is used, the stable control and purification of the particle size of the carbonylation molten intermediate are realized, the problems of caking and wide crystal size distribution in the rapid cooling and crystallization process are solved, and the continuous and efficient production is facilitated and the engineering scale-up is easy.

Description

Technical Field

[0001] The present invention belongs to the technical field of fine chemical purification, and relates to a cooling purification device and a cooling purification system for an isocyanate carbonylation intermediate, and in particular to a continuous cooling purification device and a system for a non-phosgene method special isocyanate carbonylation intermediate. Background Art

[0002] Non-phosgene specialty isocyanate technology does not use highly toxic phosgene as raw material. It mainly obtains specialty isocyanates through carbonylation and thermal decomposition, and has the characteristics of low cost and high safety.

[0003] Non-phosgene isocyanate carbonylation intermediates are generally obtained from the carbonylation reaction liquid through multi-stage distillation and water washing. In the water washing purification process, the molten carbonylation liquid is often directly passed into the water solution. This can be divided into two methods: cold washing and hot washing. Among them, cold washing is the rapid cooling and washing of the molten carbonylation liquid in the water solution. The washing process often leads to problems such as reaction intermediate agglomeration, uneven crystal size, insufficient contact with the water solution, poor water washing effect, high water consumption, and multiple water circulation. Hot washing is the continuous washing of the carbonylation liquid in the water solution while the carbonylation liquid is kept in a molten state. After the hot washing, the water is usually separated by oil-water separation. The carbonylation intermediates in the carbonylation liquid have a high solubility in the hot water solution, which can lead to low carbonylation intermediate yields during the purification process. Both of these washing methods seriously affect the scale-up and continuous production of cooling purification equipment.

[0004] Therefore, it is urgent to design and develop a cooling and purification device and a cooling and purification system for isocyanate carbonylation intermediates to overcome the defects of the existing technology and meet the actual application needs. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a cooling and purification device and cooling and purification system for isocyanate carbonylation intermediates. In the present invention, through the specific design of the spray granulation zone and the liquid phase washing zone, a method combining spray granulation, spray cooling and suspended particle liquid phase water washing is used to achieve stable control and purification of the particle size of continuously cooled particles of the carbonylation molten intermediate, solve the problems of agglomeration and wide crystal size distribution in the rapid cooling crystallization process, facilitate continuous and efficient production and facilitate engineering scale-up.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In the first aspect, the present invention provides a cooling and purification device for isocyanate carbonylation intermediates, the cooling and purification device comprising a cylinder, the bottom of the cylinder being a conical structure, a drain port being provided near the tip of the conical structure, and the cylinder being divided into a spray granulation zone and a liquid phase washing zone in sequence along the direction of the material; the spray granulation zone comprising a granulation system and a cooling system arranged in sequence along the direction of the material, an exhaust port being provided on the side wall of the cylinder between the granulation system and the cooling system; the liquid phase washing zone comprising a stirring system and a vent member arranged in sequence along the direction of the material, an overflow port being provided on the side wall of the cylinder between the stirring system and the vent member, and the vent member being provided in the conical structure and close to the drain port.

[0008] In the present invention, by specifically designing the spray granulation zone and the liquid phase washing zone, a method combining spray granulation, spray cooling and liquid phase water washing of suspended particles is used to achieve stable control and purification of the particle size of the continuously cooled particles of the carbonylation molten intermediate, thereby solving the problems of agglomeration and wide crystal size distribution in the rapid cooling crystallization process, facilitating continuous and efficient production and facilitating engineering scale-up.

[0009] It should be noted that the present invention does not impose any special restrictions on the material and size of the cylinder, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0010] It should be noted that the present invention does not specifically limit the specific size, shape and number of the feed port, air inlet, liquid discharge port, exhaust port and overflow port. Those skilled in the art can make adaptive adjustments based on actual conditions, and any design similar to the present invention falls within the scope of protection of the present invention.

[0011] As a preferred technical solution of the present invention, a feed port and an air inlet are respectively provided on the top of the cylinder.

[0012] It should be noted that, in the present invention, the feed port and the air inlet are arranged on the top of the cylinder body so as to cooperate with the components inside the cylinder body to achieve a better injection force of the material and the gas phase.

[0013] Preferably, the granulation system includes an ejector, a deflector and a guide tube, the ejector is arranged near the feed port, the deflector is arranged above the guide tube, and one end of the guide tube away from the deflector is arranged in the liquid phase in the liquid phase washing zone.

[0014] It should be noted that the specific structural design of the ejector, deflector tube and guide tube in the present invention ensures the effects of molten liquid injection and high-shear particle formation by inert gas, rapid cooling and atomization washing by spray cooler, and achieves the goal of uniform particle formation of molten liquid and sufficient contact and cooling between washing liquid and particles.

[0015] Preferably, the ejector is an ejection sleeve, which comprises an inner tube and an outer tube which are sequentially sleeved from the inside to the outside, wherein the inner tube is used for the passage of materials, and the outer tube is used for the passage of gas phase.

[0016] It should be noted that the present invention does not impose any special restrictions on the specific material and quantity of the injection sleeves, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0017] Preferably, the deflector cylinder is an annular deflector cylinder.

[0018] Preferably, the annular edge of the annular deflector cylinder is fixedly connected to the inner surface of the cylinder body.

[0019] Preferably, the annular deflector and the ejector are coaxially arranged.

[0020] It should be noted that the present invention does not impose any special restrictions on the specific material, quantity, and arrangement of the annular deflector cylinder and the deflector plates, and those skilled in the art may make adaptive adjustments based on actual conditions.

[0021] Preferably, the guide cylinder includes an upper guide cylinder and a lower guide cylinder which are sequentially arranged along the direction of the material.

[0022] Preferably, the diversion upper cylinder includes a large diameter end and a small diameter end.

[0023] Preferably, the edge of the large diameter end is fixedly connected to the inner surface of the cylinder, the small diameter end is fixedly connected to the guide lower cylinder, and the end of the guide lower cylinder away from the guide upper cylinder is arranged in the liquid phase in the liquid phase washing zone.

[0024] It should be noted that the edge of the large diameter end of the guide tube in the present invention is fixedly connected to the inner surface of the cylinder body, and the small diameter end is fixedly connected to the guide lower tube, presenting an inverted frustum shape. Combined with the specific design of the guide lower tube, the liquid phase diversion effect is improved.

[0025] It should be noted that the present invention does not impose any special restrictions on the specific material and quantity of the guide tube, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0026] Preferably, the exhaust port is provided on a side of the cylinder body corresponding to the guide upper cylinder.

[0027] Preferably, the overflow port is provided on a side of the cylinder body corresponding to the flow guide lower cylinder.

[0028] It should be noted that the present invention adopts the form of top feeding and side overflow discharge by design, so that the overall material flow is stable, and the generated crystals or particles are completely purified without causing problems of agglomeration and wide crystal size distribution.

[0029] As a preferred technical solution of the present invention, the injector is provided with at least one, for example, it can be 1, 2, 3, 4, 5, etc., but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0030] Preferably, an injection hole is provided at one end of the injector away from the feed port.

[0031] Preferably, the top of the deflector cylinder is arranged above the injection hole.

[0032] Preferably, the diameter of the deflector cylinder is between the diameter of the large diameter end and the diameter of the small diameter end.

[0033] It should be noted that the diameter of the deflector tube in the present invention is between the diameter of the large diameter end and the diameter of the small diameter end. This is because at this size, the inert gas injected by the injector can undergo partial gas-solid separation and then return to the injector position along the area between the deflector tube and the inner wall of the purification device. This can effectively limit the small particles formed by the injection from returning upward, improve the uniformity of the particle size, and at the same time reduce the amount of injected inert gas.

[0034] Preferably, the inner surface of the diversion upper cylinder is smooth.

[0035] Preferably, the roughness of the inner surface of the guide upper cylinder is ≤0.2μm, for example, it can be 0.2μm, 0.18μm, 0.16μm, 0.14μm, 0.12μm, 0.1μm, etc., but is not limited to the listed values, and other unlisted values ​​within this numerical range are also applicable.

[0036] The inner surface of the guide upper cylinder in the present invention is smooth and has a roughness of ≤0.2μm because this design allows the solid particles formed by the spray to fall into the cooling and washing area by gravity when they fall into the guide upper cylinder, thereby avoiding excessive accumulation of solid materials in the guide upper cylinder, which affects the stability of the operation of the upper spray granulation area.

[0037] Preferably, the flow guide lower cylinder is a straight cylinder.

[0038] Preferably, the diameter of the guide lower cylinder is 0.5 to 0.7 times the maximum diameter of the cylinder body, for example, it can be 0.5 times, 0.55 times, 0.6 times, 0.65 times, 0.7 times, etc., but is not limited to the listed values. Other unlisted values ​​within this numerical range are also applicable.

[0039] The diameter of the guide lower cylinder in the present invention is 0.5 to 0.7 times the maximum diameter of the cylinder because this design can ensure the washing time of the material particles and the cooling washing liquid in the guide lower cylinder by flat paddle stirring, and ensure the time for the lower paddle stirring suspension to be fully mixed and stable.

[0040] As a preferred technical solution of the present invention, the cooling system includes an annular pipeline, a spray cooler and a gas filter. The annular pipeline is sleeved on one end of the guide lower tube close to the guide upper tube, the spray cooler is arranged on the annular pipeline, and the gas filter is arranged below the spray cooler.

[0041] It should be noted that the present invention does not impose any special restrictions on the specific materials and quantities of the annular pipeline, the spray cooler, and the gas filter, and those skilled in the art may make adaptive adjustments based on actual conditions.

[0042] Preferably, the nozzle of the spray cooler is inclined downward and toward the axis, so as to cool the gas and solid particles flowing through the guide down tube.

[0043] Preferably, the gas filter is arranged on the flow guide lower cylinder.

[0044] Preferably, the filtration accuracy of the gas filter is 1 to 10 μm, for example, it can be 1 μm, 2 μm, 4 μm, 6 μm, 8 μm, 10 μm, etc., but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0045] The filtration accuracy of the gas filter in the present invention is 1 to 10 μm because 99.9% of the cooling material particles entrained in the gas can be intercepted within this size range; if it is not within this range, such as the filtration accuracy is too large, some particles will be directly carried out through the gas phase port without washing, resulting in reduced yield and purity and damage to the circulating gas compression and reuse equipment; if the filtration accuracy is too small, it will cause the pressure difference between the inside and outside of the device to increase, or the gas enters the liquid layer and enters the overflow area in the form of bubbles, causing the device to vibrate and the purity to be significantly reduced, affecting the stability of operation.

[0046] It should be noted that the gas filter in the present invention can be an annular filter or a filter composed of multiple rectangular filter sheets, and the spray liquid entering from the liquid inlet can wash the filter to ensure the accuracy of the filter.

[0047] Preferably, a liquid inlet is provided on a side of the cylinder that is flush with the annular pipeline, and the liquid inlet is connected to the annular pipeline through a liquid inlet pipe.

[0048] As a preferred technical solution of the present invention, the stirring system includes a double-layer stirring paddle, a support column and a stirring motor, one end of the support column is fixedly connected to the double-layer stirring paddle, and the other end passes through the discharge port and is externally connected to the stirring motor, and the double-layer stirring paddle and the stirring motor are electrically connected.

[0049] It should be noted that the present invention does not impose any special restrictions on the specific materials, sizes and quantities of the double-layer stirring paddles, support columns and stirring motors, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0050] Preferably, the double-layer stirring paddle is arranged in the flow guide lower cylinder.

[0051] Preferably, the double-layer stirring paddle includes a flat paddle and an anchor paddle sequentially arranged along the direction of the material.

[0052] Preferably, the anchor propeller is a V-shaped anchor propeller.

[0053] It should be noted that the double-layer stirring paddles designed in the present invention, and the flat paddles and V-shaped anchor paddles are because the reason is that the structure cooperates with the specific design of the guide tube and the ventilation cone to achieve the uniform suspension of the settled particles by bubbles, and the particulate material and the washing liquid can be fully stirred and washed in the guide tube, thereby enhancing the washing effect. Moreover, through the cooperation of the V-shaped anchor paddle and the ventilation cone, bubbles can be blown to stir and suspend the particles deposited at the bottom, thereby enhancing the mass transfer of solid and liquid, improving the washing effect of the carbonylation intermediate, and ensuring the uniformity of the particle size of the carbonylation intermediate particles after washing. The process is simple, safe and reliable.

[0054] Preferably, the flat paddle and the anchor paddle are coaxially arranged, and the distance between the flat paddle and the anchor paddle is 0.16 to 0.25 times the height of the cylinder, for example, it can be 0.16 times, 0.18 times, 0.2 times, 0.22 times, 0.24 times, 0.25 times, etc., but is not limited to the listed values, and other unlisted values ​​within this numerical range are also applicable.

[0055] In the present invention, the distance between the flat paddle and the anchor paddle is 0.16 to 0.25 times the height of the cylinder because within this size range, most particles can be fully washed under the stirring of the flat paddle, and at the same time, a small amount of oversized particles are fully settled to the bottom of the purification device and stirred up by the V-shaped anchor paddle to form a homogeneous suspension, thereby better exerting the synergistic effect of the two paddles; if it is not within this range, some particles will not be fully washed, resulting in direct carry-out, resulting in insufficient purity of the washed material.

[0056] As a preferred technical solution of the present invention, the ventilator is a vent cone, and a through hole is provided on the surface of the vent cone.

[0057] It should be noted that the present invention does not impose any special restrictions on the size, number and shape of the through holes, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0058] Preferably, the tip of the ventilation cone is arranged corresponding to the tip of the conical structure.

[0059] Preferably, there is at least one through hole, for example, 1, 2, 3, 4, 5, etc., but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0060] Preferably, the diameter of the through hole is 1 to 3 mm, for example, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0061] Preferably, the air outlet pipe is provided with an air hole, and the air hole is used to ventilate the ventilation cone.

[0062] Preferably, the surface roughness of the conical structure is ≤0.4 μm, for example, it can be 0.4 μm, 0.3 μm, 0.2 μm, 0.1 μm, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0063] The surface roughness of the conical structure in the present invention is ≤0.4 μm because within this range, a small amount of solid material that falls to the bottom of the cone can gradually slide to the conical ventilation cone, and the solid material is re-suspended by the ventilation cone; if it is not within this range, the solid material will accumulate at the bottom, affecting the suspension of the bottom material and the washing effect.

[0064] As a preferred technical solution of the present invention, the air inlet is used for inert gas intake, and the inert gas is carbon dioxide and nitrogen.

[0065] Preferably, the feed port is used for feeding a crude intermediate, and the crude intermediate is a melting point feed.

[0066] It should be noted that the crude intermediate in the present invention refers to crude alkyl dicarbamate, and the melting point of the feed may be 100-120°C.

[0067] Preferably, the volume ratio of the inert gas to the crude intermediate is (4-10):1, for example, it can be 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, etc., but is not limited to the listed values, and other unlisted values ​​within this numerical range are also applicable.

[0068] Preferably, the inlet temperature of the inert gas is 25-60°C, for example, it can be 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, etc., but is not limited to the listed values, and other unlisted values ​​within this numerical range are also applicable.

[0069] The inlet temperature of the inert gas in the present invention is 25-60°C because within this range the molten intermediate can be quickly cooled and formed, and temperature control can be achieved during spraying to enhance the washing effect. If it is not within this range, the washing effect will be poor, or the particles will not be able to be formed, and stable operation and particle size control cannot be guaranteed.

[0070] Preferably, the pressure of the inert gas is greater than the pressure of the cooling and purification device.

[0071] Preferably, the pressure difference between the inert gas and the cooling purification device is 0.05 to 0.2 MPa, for example, it can be 0.05 MPa, 0.08 MPa, 0.1 MPa, 0.13 MPa, 0.15 MPa, 0.16 MPa, 0.18 MPa, 0.2 MPa, etc., but is not limited to the listed values, and other unlisted values ​​within this numerical range are also applicable.

[0072] The pressure difference between the inert gas and the cooling purification device in the present invention is 0.05-0.2 MPa because within this range, the molten liquid droplets can be dispersed by high shear, the particle size can be controlled, and the particle size distribution can be uniform; if it is not within this range, the feed liquid will cool into agglomerates or the particle size will be too small.

[0073] Preferably, the mass ratio of the spray amount of the cooling system to the feed amount of the crude intermediate is (2 to 4):1, for example, it can be 2:1, 2.5:1, 3:1, 3.5:1, 4:1, etc., but is not limited to the listed values, and other unlisted values ​​within this numerical range are also applicable.

[0074] In the present invention, the mass ratio of the spraying amount of the cooling system to the feed amount of the crude intermediate is (2-4):1, because within this range, the impurity components in the crude intermediate can be fully removed; if it is not within this range, the purified liquid solid material will fail to meet the purity requirements.

[0075] Preferably, the spray liquid used in the cooling system is desalted water or dimethyl carbonate.

[0076] It should be noted that the desalted water in the present invention is a common term for water used in industrial projects, and can be considered to be of a water quality similar to that of laboratory deionized water.

[0077] In a second aspect, the present invention provides a cooling purification system, which includes a cooling purification device, a centrifugal device and a melting device connected in sequence by pipelines. The cooling purification device adopts the cooling purification device described in the first aspect.

[0078] As a preferred technical solution of the present invention, the centrifugal device is a centrifuge.

[0079] It should be noted that the present invention does not impose any special restrictions on the model and shape of the centrifuge, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0080] Preferably, the centrifuge is a two-stage pusher centrifuge.

[0081] Preferably, the melting device is a melting tank.

[0082] It should be noted that the present invention does not impose any special restrictions on the model and shape of the melting tank, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0083] As a preferred technical solution of the present invention, the mass ratio of the amount of eluent used in the centrifugal device to the material at the feed port is (0.5-1):1, for example, it can be 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, etc., but is not limited to the listed values, and other unlisted values ​​within this numerical range are also applicable.

[0084] The mass ratio of the eluent volume to the material at the feed port used in the centrifugal device of the present invention is (0.5-1):1, because within this range, the purity of the carbonylation intermediate crystals can meet the requirements; if it is not within this range, the purity of the carbonylation intermediate crystals will be low.

[0085] Preferably, the temperature of the melting device is higher than the melting point of the purified material.

[0086] It should be noted that the purified material in the present invention refers to crude alkyl diurethane, which has a melting point of 100-120°C. The melting point is set according to the corresponding specific material. Those skilled in the art will know that all such cases are within the scope of protection of the present invention.

[0087] Preferably, the difference between the temperature of the melting device and the melting point of the purified material is 5 to 10°C, for example, it can be 5°C, 6°C, 7°C, 8°C, 9°C, 10°C, etc., but is not limited to the listed values. Other unlisted values ​​within this numerical range are also applicable.

[0088] The difference between the temperature of the melting device and the melting point of the purified material in the present invention is 5 to 10°C because the material can be fully melted and the water can be fully removed within this range; if it is not within this range, such as if the temperature is too low, the material cannot be pumped and is prone to clogging the pipeline; if the temperature is too high, long-term retention will cause the material to deteriorate.

[0089] Preferably, the eluent used in the centrifugal device is desalted water or dimethyl carbonate.

[0090] Exemplarily, the purification process of the cooling purification system in the present invention includes:

[0091] The crude carbonylation intermediates pass through a cooling and purification unit, a centrifugal unit, and a melting unit in sequence to produce a high-purity molten intermediate, which is then fed to the downstream pyrolysis unit. The inert gas separated by the cooling and purification unit can be compressed and reused after gas-liquid separation. The washing liquid separated by the centrifugal unit can be reused as water replenishment, with the excess being sent to wastewater treatment. The overhead vapor from the melting unit can be condensed and then fed back to the centrifugal unit as eluent.

[0092] Compared with the prior art, the present invention has the following beneficial effects:

[0093] In the present invention, by specifically designing the spray granulation zone and the liquid-phase washing zone, a method combining spray granulation, spray cooling and liquid-phase water washing of suspended particles is used to achieve stable control and purification of the particle size of continuously cooled particles of the carbonylation molten intermediate. This solves the problems of large washing liquid consumption and large circulation volume, high impurity content, easy agglomeration of the intermediate and uneven particle size distribution in the cold washing process of the existing carbonylation intermediate washing and purification device. It also solves the low efficiency problems such as low yield of the carbonylation intermediate in the hot washing process. It also solves the problems of agglomeration and wide crystal size distribution in the rapid cooling crystallization process. The process is efficient and safe, conducive to continuous and efficient production and easy to scale up.

[0094] Furthermore, the cooling purification device of the present invention realizes the purification, continuous and efficient production of carbonylation intermediates. The impurity content after washing (excluding the washing liquid) can be reduced to ≤0.2%, and the intermediate crystal particle size distribution is narrow, 150 to 350 μm. After continuous centrifugal elution, the impurity content after washing (excluding the washing liquid) can be reduced to ≤0.05%. After melt drying, it can meet the pyrolysis feed standard. The purity of the carbonylation intermediate can reach more than 99.6%, and the yield of the carbonylation intermediate can reach more than 99%. BRIEF DESCRIPTION OF THE DRAWINGS

[0095] Figure 1 A schematic structural diagram of a cooling and purification device provided in accordance with a specific embodiment of the present invention;

[0096] Figure 2 A schematic structural diagram of a cooling and purification system provided in accordance with a specific embodiment of the present invention;

[0097] Among them, 1- ejector; 2- baffle cylinder; 3- guide cylinder; 4- spray cooler; 5- gas filter; 6- flat paddle; 7- V-anchor paddle; 8- double-layer stirring paddle; 9- conical structure; 10- ventilation cone; 11- stirring motor; 12- cooling and purification device; 13- centrifugal device; 14- melting device;

[0098] a-feed port; b-air inlet; c-liquid inlet; d-air hole; e-liquid discharge port; f-overflow port; g-exhaust port; h-eluent; i-washing liquid; j-evaporating gas; k-carbonylation molten intermediate; l-recycled liquid. DETAILED DESCRIPTION

[0099] It should be understood that, in the description of the present invention, the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0100] It should be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "disposed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0101] Those skilled in the art should understand that the present invention must include necessary pipelines, conventional valves and general pump equipment for realizing a complete process, but the above content does not belong to the main invention point of the present invention. Those skilled in the art can add layouts on their own based on the process flow and equipment structure selection, and the present invention does not make special requirements and specific limitations on this.

[0102] The technical solution of the present invention will be further described below with reference to the accompanying drawings and through specific implementation methods.

[0103] In one embodiment, the present invention provides a cooling and purification device 12 for isocyanate carbonylation intermediates, such as Figure 1As shown, the cooling purification device 12 includes a cylinder, the top of the cylinder is respectively provided with a feed port a and an air inlet b, the bottom of the cylinder is a conical structure 9, and a drain port e is provided near the tip of the conical structure 9. The cylinder is divided into a spray granulation zone and a liquid phase washing zone in sequence along the direction of the material; the spray granulation zone includes a granulation system and a cooling system arranged in sequence along the direction of the material, and an exhaust port g is provided on the side wall of the cylinder between the granulation system and the cooling system; the liquid phase washing zone includes a stirring system and a vent member arranged in sequence along the direction of the material, and an overflow port f is provided on the side wall of the cylinder between the stirring system and the vent member, and the vent member is arranged in the conical structure 9 and close to the drain port e.

[0104] In the present invention, by specifically designing the spray granulation zone and the liquid phase washing zone, a method combining spray granulation, spray cooling and liquid phase water washing of suspended particles is used to achieve stable control and purification of the particle size of the continuously cooled particles of the carbonylation molten intermediate K, thereby solving the problems of agglomeration and wide crystal size distribution in the rapid cooling crystallization process, facilitating continuous and efficient production and facilitating engineering scale-up.

[0105] It should be noted that the present invention does not impose any special restrictions on the material and size of the cylinder, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0106] It should be noted that the present invention does not impose any special restrictions on the specific size, shape and number of the feed port a, air inlet b, liquid discharge port e, exhaust port g and overflow port f. Those skilled in the art can make adaptive adjustments based on actual conditions, and any design similar to the present invention falls within the scope of protection of the present invention.

[0107] The granulation system includes an ejector 1, a deflector 2 and a guide tube 3. The ejector 1 is arranged near the feed port a, the deflector 2 is arranged above the guide tube 3, and the end of the guide tube 3 away from the deflector 2 is arranged in the liquid phase in the liquid phase washing zone.

[0108] It should be noted that the specific structural design of the ejector 1, the deflector tube 2 and the guide tube 3 in the present invention ensures the injection of the molten liquid and the high-shear particle formation of the inert gas, the rapid cooling and atomization washing by the spray cooler 4, and the goal of uniform particle formation of the molten liquid and sufficient contact and cooling of the washing liquid i with the particles.

[0109] The ejector 1 is an ejection sleeve, which includes an inner tube and an outer tube arranged sequentially from the inside to the outside. The inner tube is used for material to pass through, and the outer tube is used for gas to pass through. It should be noted that the specific material and number of the ejection sleeve are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0110] The baffle 2 is an annular baffle 2, the annular edge of which is fixedly connected to the inner surface of the cylinder body, and the annular baffle 2 is coaxially arranged with the ejector 1. It should be noted that the specific material, number, and arrangement of the baffles of the annular baffle 2 are not particularly limited in the present invention, and those skilled in the art may make adaptive adjustments based on actual conditions.

[0111] The guide cylinder 3 includes an upper guide cylinder and a lower guide cylinder arranged in sequence along the direction of the material. The upper guide cylinder includes a large diameter end and a small diameter end. The edge of the large diameter end is fixedly connected to the inner surface of the cylinder body, and the small diameter end is fixedly connected to the lower guide cylinder. The end of the lower guide cylinder away from the upper guide cylinder is arranged in the liquid phase in the liquid phase washing area.

[0112] It should be noted that the large-diameter end edge of the flow guide tube 3 in the present invention is fixedly connected to the inner surface of the cylinder body, while the small-diameter end is fixedly connected to the lower flow guide tube, forming an inverted frustum. This, combined with the specific design of the lower flow guide tube, enhances the liquid phase diversion effect. It should be noted that the specific material and number of flow guide tubes 3 are not particularly limited in the present invention, and those skilled in the art may make adaptive adjustments based on actual circumstances.

[0113] The exhaust port g is located on the side of the cylinder corresponding to the upper guide cylinder, and the overflow port f is located on the side of the cylinder corresponding to the lower guide cylinder. It should be noted that the present invention utilizes top feeding and side overflow discharge to ensure a stable overall material flow and completely purify the resulting crystals or particles, eliminating problems such as agglomeration and a wide distribution of crystal sizes.

[0114] The injector 1 is provided with at least one, for example, it can be 1, 2, 3, 4, 5, etc., but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0115] An injection hole is provided at one end of the injector 1 away from the feed port a, and the top of the deflector tube 2 is provided above the injection hole. The diameter of the deflector tube 2 is between the diameter of the large diameter end and the diameter of the small diameter end. The inner surface of the guide upper tube is smooth, and the roughness of the inner surface of the guide upper tube is ≤0.2μm, for example, it can be 0.2μm, 0.18μm, 0.16μm, 0.14μm, 0.12μm, 0.1μm, etc., but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0116] The lower guide tube is a straight cylinder, and the diameter of the lower guide tube is 0.5 to 0.7 times the maximum diameter of the cylinder, for example, it can be 0.5 times, 0.55 times, 0.6 times, 0.65 times, 0.7 times, etc., but is not limited to the listed values. Other values ​​not listed within this numerical range are also applicable.

[0117] The cooling system includes an annular pipeline, a spray cooler 4, and a gas filter 5. The annular pipeline is sleeved around one end of the lower guide tube near the upper guide tube. The spray cooler 4 is arranged on the annular pipeline, and the gas filter 5 is arranged below the spray cooler 4. It should be noted that the specific materials and quantities of the annular pipeline, spray cooler 4, and gas filter 5 are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0118] The spray cooler 4, with its nozzle angled downward and oriented toward the axis, cools the gas and solid particles flowing through the lower guide tube. A gas filter 5, with a filtration accuracy of 1 to 10 μm, is located on the lower guide tube. A liquid inlet c is provided on the side of the tube flush with the annular pipeline. This inlet c is connected to the annular pipeline via a liquid inlet pipe.

[0119] The stirring system includes a double-layer stirring paddle 8, a support column, and a stirring motor 11. One end of the support column is fixedly connected to the double-layer stirring paddle 8, and the other end extends through the discharge port e and is externally connected to the stirring motor 11. The double-layer stirring paddle 8 and the stirring motor 11 are electrically connected. It should be noted that the specific materials, sizes, and quantities of the double-layer stirring paddle 8, the support column, and the stirring motor 11 are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0120] The double-layer stirring paddle 8 is arranged in the guide lower cylinder. The double-layer stirring paddle 8 includes a flat paddle 6 and an anchor paddle arranged in sequence along the direction of the material. The anchor paddle is a V-shaped anchor paddle 7.

[0121] It should be noted that the double-layer stirring paddle 8 is designed in the present invention, and the flat paddle 6 and the V-shaped anchor paddle 7 are because this structure is combined with the specific design of the guide tube 3 and the ventilation cone 10 to achieve the uniform suspension of the settled particles by bubbles, and the particulate material and the washing liquid i can be fully stirred and washed in the guide tube, thereby enhancing the washing effect. Moreover, through the cooperation of the V-shaped anchor paddle 7 and the ventilation cone 10, bubbles can be blown to stir and suspend the particles deposited at the bottom, thereby enhancing the mass transfer of solid and liquid, improving the washing effect of the carbonylation intermediate, and ensuring the uniformity of the particle size of the carbonylation intermediate particles after washing. The process is simple, safe and reliable.

[0122] The flat paddle 6 and the anchor paddle are coaxially arranged, and the distance between the flat paddle 6 and the anchor paddle is 0.16 to 0.25 times the height of the cylinder, for example, it can be 0.16 times, 0.18 times, 0.2 times, 0.22 times, 0.24 times, 0.25 times, etc., but is not limited to the listed values, and other unlisted values ​​within this numerical range are also applicable.

[0123] The vent member is a vent cone, the tip of which corresponds to the tip of the conical structure 9, and the surface of the vent cone 10 is provided with through holes. It should be noted that the size, number, and shape of the through holes are not particularly limited in the present invention, and those skilled in the art may make adaptive adjustments based on actual conditions.

[0124] At least one through hole is provided, and for example, there can be 1, 2, 3, 4, 5, etc., but the number is not limited to the values ​​listed, and other values ​​not listed within the numerical range are also applicable. The diameter of the through hole is 1 to 3 mm, for example, it can be 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, etc., but the number is not limited to the values ​​listed, and other values ​​not listed within the numerical range are also applicable.

[0125] An air hole d is provided on the air outlet pipe of the liquid discharge port e of the vent cone 10 , and the air hole d is used to ventilate the vent cone 10 .

[0126] The surface roughness of the conical structure 9 is ≤ 0.4 μm, for example, it can be 0.4 μm, 0.3 μm, 0.2 μm, 0.1 μm, etc., but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0127] The air inlet b is used for inert gas intake, and the inert gases are carbon dioxide and nitrogen. The feed port a is used for crude intermediate feeding, and the crude intermediate is melting point feed. The volume ratio of the inert gas to the crude intermediate is (4 to 10):1, for example, it can be 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, etc., but is not limited to the listed values. Other values ​​not listed within this numerical range are also applicable.

[0128] The inlet temperature of the inert gas is 25-60°C, for example, it can be 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, etc., but is not limited to the listed values. Other values ​​not listed within this numerical range are also applicable.

[0129] The pressure of the inert gas is greater than the pressure of the cooling purification device 12. The pressure difference between the inert gas and the cooling purification device 12 is 0.05 to 0.2 MPa. For example, it can be 0.05 MPa, 0.08 MPa, 0.1 MPa, 0.13 MPa, 0.15 MPa, 0.16 MPa, 0.18 MPa, 0.2 MPa, etc., but is not limited to the listed values. Other values ​​not listed within this numerical range are also applicable.

[0130] The mass ratio of the spray volume of the cooling system to the feed volume of the crude intermediate is (2-4):1, and can be, for example, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, etc., but is not limited to the values ​​listed above, and other values ​​not listed within this numerical range are also applicable. The spray liquid used in the cooling system is desalted water or dimethyl carbonate.

[0131] In another specific embodiment, the present invention provides a cooling purification system, which includes a cooling purification device 12, a centrifugal device 13 and a melting device 14 connected in sequence by pipelines. The cooling purification device 12 adopts the above-mentioned cooling purification device 12.

[0132] The centrifugal device 13 is a centrifuge, and further, the centrifuge is a two-stage push-plate centrifuge. The eluent h used in the centrifugal device 13 is desalted water or dimethyl carbonate. It should be noted that the present invention does not specifically limit the model and shape of the centrifuge, and those skilled in the art can make adaptive adjustments according to actual conditions.

[0133] The melting device 14 is a melting tank. It should be noted that the present invention does not impose any particular restrictions on the type and shape of the melting tank, and those skilled in the art can make adaptive adjustments based on actual conditions.

[0134] The mass ratio of the eluent h used in the centrifugal device 13 to the material at the feed port a is (0.5-1):1, for example, it can be 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, etc., but is not limited to the listed values. Other values ​​not listed within this numerical range are also applicable.

[0135] The temperature of the melting device 14 is higher than the melting point of the purified material. It should be noted that the melting point in the present invention is set according to the corresponding specific material, and those skilled in the art will know that all such cases fall within the scope of protection of the present invention.

[0136] The difference between the temperature of the melting device 14 and the melting point of the purified material is 5 to 10°C, for example, it can be 5°C, 6°C, 7°C, 8°C, 9°C, 10°C, etc., but is not limited to the listed values. Other unlisted values ​​within this numerical range are also applicable.

[0137] For example, the method of using the cooling purification device 12 of the present invention is as follows: Figure 1 Shown, including:

[0138] The molten crude carbonylation intermediate enters the inner tube of the ejector 1 at the top of the cooling and purification unit 12 through feed port a. Inert gas enters the outer tube of the ejector 1 through gas inlet port b. Under the shearing effect of the inert gas jet, the molten liquid is rapidly dispersed and cooled into particles. The gas, carrying the particles, descends along the deflector tube 2. A small amount of gas circulates up along the upper guide tube to the ejector 1, while the majority descends to the lower guide tube. There, the particles are spray-cooled in the spray cooler 4 and thoroughly contacted with the particles for washing. The vast majority of the particles fall to the bottom liquid layer, while a small amount is filtered through the gas filter 5 and discharged as exhaust gas through the exhaust port g. Under the agitation of the flat paddle 6, the particles are thoroughly mixed and washed with the washing liquid i. Gravity causes the particle-containing liquid to move downward, with some larger particles falling to the bottom of the unit. The anchor paddle and the gas in the aeration cone 10 cause the larger particles to float upward, forming a suspended multiphase flow at the bottom of the unit for thorough washing. The washed carbonylation intermediate liquid overflows through the overflow port f to downstream equipment.

[0139] The crude carbonylation intermediate passes through a cooling and purification unit 12, a centrifugal unit 13, and a melting unit 14 in sequence to obtain a high-purity molten intermediate, which is then delivered to the downstream pyrolysis unit. The inert gas separated by the cooling and purification unit 12 can be compressed and reused after gas-liquid separation. The washing liquid i separated by the centrifugal unit 13 can be partially reused as makeup water (recyclable liquid l), with the excess being sent to wastewater treatment. The overhead vapor j from the melting unit 14 can be condensed and then returned to the centrifugal unit 13 as eluent h.

[0140] Furthermore, the purification process of the cooling purification system in the present invention is as follows: Figure 2 As shown. Includes:

[0141] The crude carbonylation intermediate melt and inert gas enter the cooling and purification unit 12 at a feed volume ratio of 4:1 to 10:1. After spray granulation, the granules are sprayed with a spray liquid in the middle of the unit, with a spray volume to intermediate feed mass ratio of 2:1 to 4:1. The tail gas is discharged through the exhaust port g and, after compression and gas-liquid separation, is returned to the air inlet b. The overflow slurry is gravity fed to a centrifuge. The centrifuge can be configured as a two-stage centrifugation unit with a primary centrifugation and a secondary elution unit. The mass ratio of the elution liquid h to the feed in the centrifuge is 0.5:1 to 1:1. The washing liquid i after centrifugation can be used as a supplementary solvent for the carbonylation reaction unit, and some is sent as waste liquid to the waste liquid treatment unit. The qualified carbonylation intermediate exiting the centrifuge is fed to a melting tank, where the temperature is controlled at approximately 5-10°C above the melting point of the carbonylation intermediate.

[0142] Example 1

[0143] This embodiment provides a purification method for a cooling purification system, wherein:

[0144] 1,6-hexanedicarbamate HDC (containing 8% of impurities aminohexylcarbamate HMC and N-methylated aminohexylcarbamate N-HMC) enters the inner tube of the injector 1 through the feed port a, and nitrogen enters the outer tube of the injector 1 through the air inlet b. The HDC liquid and nitrogen are in a feed volume ratio of 5:1. Under the spray shear of the nitrogen, the molten liquid is quickly dispersed and cooled into particles. The initial particle size of the particles is 200 μm. The nitrogen carries the particles and falls along the deflector tube 2. A small amount of nitrogen circulates along the upper guide tube and rises to the injector 1, and most of it falls to the lower guide tube. It is sprayed and cooled by the spray cooler 4 to ensure that the water liquid and the particles are fully contacted and washed. The mass ratio of the spray water volume to the intermediate feed is 2.5:1. Most of the particles fall to the bottom liquid layer. The small amount of particles entrained by the nitrogen are filtered by the gas filter 5, and the remaining nitrogen is discharged as exhaust gas through the exhaust port g.

[0145] Under the stirring of the flat paddle 6, the particles are fully mixed and washed with the washing liquid i, and under the action of gravity, the particle-containing liquid moves downward, and some larger particles of about 350 μm fall to the bottom of the device. Under the action of the anchor paddle and the nitrogen in the ventilation cone 10, the larger particles float upward, forming a suspended multiphase flow at the bottom of the device for sufficient washing. The washed carbonylation intermediate liquid overflows into the centrifuge through the overflow port f.

[0146] The particle size is essentially controlled at 260 μm. The centrifuge is a two-stage pusher centrifuge with a water-to-liquid mass ratio of 0.5:1. The wash water after centrifugation is sent to the waste liquid treatment unit as waste liquid. The water-containing solids enter the melting tank at a melting temperature of 120°C and are then sent to the downstream pyrolysis unit.

[0147] After treatment in the purification cooling system, the crystal particle size ranges from 200 to 300 μm, and the HMC and N-HMC impurity content in 1,6-hexanedicarbamate is reduced to 0.15%. After centrifugal elution, the impurity content is further reduced to 0.04%. The yield of 1,6-hexanedicarbamate during the cooling purification process is 99.1%.

[0148] In summary, the present invention achieves stable control and purification of the particle size of the continuously cooled particles of the carbonylation molten intermediate K through the specific design of the spray granulation zone and the liquid phase washing zone, using a method that combines spray granulation, spray cooling and liquid phase water washing of suspended particles, and solves the problems of agglomeration and wide crystal size distribution in the rapid cooling crystallization process, which is conducive to continuous and efficient production and easy to scale up in engineering.

[0149] The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and disclosure scope of the present invention.

Claims

1. A cooling and purification device for isocyanate carbonylation intermediates, characterized in that: The cooling and purification device comprises a cylinder, the bottom of which is a conical structure, a liquid discharge port is provided near the tip of the conical structure, and the cylinder is divided into a spray granulation zone and a liquid phase washing zone in sequence along the direction of the material; The spray granulation zone includes a granulation system and a cooling system arranged in sequence along the direction of the material, and an exhaust port is provided on the side wall of the cylinder between the granulation system and the cooling system; The liquid phase washing zone includes a stirring system and a vent member arranged in sequence along the direction of the material, an overflow port is provided on the side wall of the cylinder between the stirring system and the vent member, and the vent member is arranged in the conical structure and close to the drain port; The cooling system includes a ring pipeline, a spray cooler and a gas filter.

2. The cooling and purification device according to claim 1, characterized in that: A feed inlet and an air inlet are respectively provided on the top of the cylinder.

3. The cooling and purification device according to claim 2, characterized in that: The granulation system includes an ejector, a deflection cylinder and a guide cylinder. The ejector is arranged near the feed port, the deflection cylinder is arranged above the guide cylinder, and one end of the guide cylinder away from the deflection cylinder is arranged in the liquid phase in the liquid phase washing zone.

4. The cooling and purification device according to claim 3, characterized in that: The ejector is an ejection sleeve, which includes an inner tube and an outer tube which are sequentially sleeved from the inside to the outside. The inner tube is used for the passage of materials, and the outer tube is used for the passage of gas phase.

5. The cooling and purification device according to claim 3, characterized in that: The deflector cylinder is an annular deflector cylinder.

6. The cooling and purification device according to claim 5, characterized in that: The annular edge of the annular deflector cylinder is fixedly connected to the inner surface of the cylinder body.

7. The cooling and purification device according to claim 6, characterized in that: The annular deflector cylinder and the ejector are coaxially arranged.

8. The cooling and purification device according to claim 3, characterized in that: The guide cylinder comprises an upper guide cylinder and a lower guide cylinder which are sequentially arranged along the direction of the material.

9. The cooling and purification device according to claim 8, characterized in that: The flow guide upper cylinder includes a large diameter end and a small diameter end.

10. The cooling and purification device according to claim 9, characterized in that: The edge of the large diameter end is fixedly connected to the inner surface of the cylinder, and the small diameter end is fixedly connected to the lower guide cylinder. One end of the lower guide cylinder away from the upper guide cylinder is arranged in the liquid phase in the liquid phase washing area.

11. The cooling and purification device according to claim 10, characterized in that: The exhaust port is arranged on a side of the cylinder body corresponding to the guide upper cylinder.

12. The cooling and purification device according to claim 11, characterized in that: The overflow port is arranged on a side of the cylinder body corresponding to the lower guide cylinder.

13. The cooling and purification device according to claim 12, characterized in that: At least one injector is provided.

14. The cooling and purification device according to claim 13, characterized in that: An injection hole is provided at one end of the injector away from the feed port.

15. The cooling and purification device according to claim 14, characterized in that: The top of the deflector cylinder is arranged above the injection hole.

16. The cooling and purification device according to claim 15, characterized in that: The diameter of the deflector tube is between the diameter of the large diameter end and the diameter of the small diameter end.

17. The cooling and purification device according to claim 16, characterized in that: The inner surface of the diversion upper cylinder is smooth.

18. The cooling and purification device according to claim 17, characterized in that: The roughness of the inner surface of the guide upper cylinder is ≤0.2 μm.

19. The cooling and purification device according to claim 18, characterized in that: The flow guide lower cylinder is a straight cylinder.

20. The cooling and purification device according to claim 19, characterized in that: The diameter of the lower guide tube is 0.5 to 0.7 times the maximum diameter of the cylinder.

21. The cooling and purification device according to claim 20, characterized in that: The annular pipeline is sleeved on one end of the guide lower tube close to the guide upper tube, the spray cooler is arranged on the annular pipeline, and the gas filter is arranged below the spray cooler.

22. The cooling and purification device according to claim 21, characterized in that: The spray cooler has a nozzle that is inclined downward and toward the axis, and is used to cool the gas and solid particles flowing through the guide down tube.

23. The cooling and purification device according to claim 22, characterized in that: The gas filter is arranged on the flow guide lower cylinder.

24. The cooling and purification device according to claim 23, characterized in that: The filtration accuracy of the gas filter is 1-10 μm.

25. The cooling and purification device according to claim 24, characterized in that: A liquid inlet is provided on one side of the cylinder that is flush with the annular pipeline, and the liquid inlet is connected to the annular pipeline through a liquid inlet pipe.

26. The cooling and purification device according to claim 25, characterized in that: The stirring system includes a double-layer stirring paddle, a support column and a stirring motor. One end of the support column is fixedly connected to the double-layer stirring paddle, and the other end passes through the discharge port and is externally connected to the stirring motor. The double-layer stirring paddle and the stirring motor are electrically connected.

27. The cooling and purification device according to claim 26, characterized in that: The double-layer stirring paddle is arranged in the lower flow guide cylinder.

28. The cooling and purification device according to claim 27, characterized in that: The double-layer stirring paddles include a flat paddle and an anchor paddle which are sequentially arranged along the direction of the material.

29. The cooling and purification device according to claim 28, characterized in that: The anchor propeller is a V-shaped anchor propeller.

30. The cooling and purification device according to claim 29, characterized in that: The flat propeller and the anchor propeller are coaxially arranged, and the distance between the flat propeller and the anchor propeller is 0.16 to 0.25 times the height of the cylinder.

31. The cooling and purification device according to claim 30, characterized in that: The ventilator is a vent cone, and a through hole is provided on the surface of the vent cone.

32. The cooling and purification device according to claim 31, characterized in that: The tip of the ventilation cone is arranged corresponding to the tip of the conical structure.

33. The cooling and purification device according to claim 31, characterized in that: There is at least one through hole.

34. The cooling and purification device according to claim 31, characterized in that: The diameter of the through hole is 1-3 mm.

35. The cooling and purification device according to claim 32, characterized in that: The surface roughness of the tapered structure is ≤0.4 μm.

36. The cooling and purification device according to claim 2, characterized in that: The gas inlet is used for inert gas intake, and the inert gas is carbon dioxide and nitrogen.

37. The cooling and purification device according to claim 36, characterized in that: The feed port is used for feeding a crude intermediate, and the crude intermediate is a melting point feed.

38. The cooling and purification device according to claim 37, characterized in that: The volume ratio of the inert gas to the crude intermediate is (4-10):

1.

39. The cooling and purification device according to claim 38, characterized in that: The inlet temperature of the inert gas is 25-60°C.

40. The cooling and purification device according to claim 39, characterized in that: The pressure of the inert gas is greater than the pressure of the cooling and purification device.

41. The cooling and purification device according to claim 40, characterized in that: The pressure difference between the inert gas and the cooling purification device is 0.05~0.2MPa.

42. The cooling and purification device according to claim 41, characterized in that: The mass ratio of the spraying amount of the cooling system to the feed amount of the crude intermediate is (2-4):

1.

43. The cooling and purification device according to claim 42, characterized in that: The spray liquid used in the cooling system is desalted water or dimethyl carbonate.

44. A cooling and purification system, characterized in that: The cooling purification system includes a cooling purification device, a centrifugal device and a melting device connected in sequence by pipelines, and the cooling purification device adopts the cooling purification device according to any one of claims 2-43.

45. The cooling and purification system according to claim 44, characterized in that: The centrifugal device is a centrifuge.

46. ​​The cooling and purification system according to claim 45, characterized in that: The centrifuge is a two-stage pusher-plate centrifuge.

47. The cooling and purification system according to claim 44, characterized in that: The melting device is a melting tank.

48. The cooling and purification system according to claim 44, characterized in that: The mass ratio of the eluent volume used in the centrifugal device to the material in the feed port is (0.5~1):

1.

49. The cooling and purification system according to claim 44, characterized in that The temperature of the melting device is higher than the melting point of the purified material.

50. The cooling and purification system according to claim 49, characterized in that: The difference between the temperature of the melting device and the melting point of the purified material is 5-10°C.

51. The cooling and purification system according to claim 44, characterized in that: The eluent used in the centrifugal device is desalted water or dimethyl carbonate.

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