High-purity melt crystallization device based on dynamic temperature control and magnetic stirring

Abstract

The utility model belongs to the technical field of melt crystallization equipment, and particularly discloses a high-purity melt crystallization device based on dynamic temperature control and magnetic stirring, which comprises a crystallizer, a sleeve body is arranged outside the crystallizer, a first temperature adjusting cavity is formed by the sleeve body and the side wall of the crystallizer, and a discharge port is arranged at the lower part of the side wall of the crystallizer. A cover body is arranged on an opening of the crystallizer, a first thermometer is installed on the cover body, a cooling column is installed on the cover body, the lower end of the cooling column extends into the crystallizer, a second temperature adjusting cavity is formed in the cooling column, a second thermometer is installed on the cooling column, and a stirring rotor is arranged in the crystallizer. And a magnetic stirrer for controlling the stirring rotor to stir materials in the crystallizer is arranged below the crystallizer. Through cooperation of dynamic temperature control and magnetic stirring technologies, the core bottlenecks of low purity, high pollution risk and high energy consumption in the traditional process are solved, and an efficient, clean and sustainable solution is provided for industrial purification of high-added-value materials.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of melt crystallization equipment, concretely relates to a high purity melt crystallization device based on dynamic temperature control and magnetic stirring. BACKGROUND

[0002] As the core process of high-purity chemicals (such as pharmaceutical intermediates, electronic-grade materials), melt crystallization technology is long limited by static temperature control, mechanical contamination and low separation efficiency. The existing equipment generally adopts fixed cooling rate to realize crystallization, for example, the layer melt crystallization technology forms supersaturation through single cooling, but static temperature control easily causes local supercooling of the melt, leading to impurity wrapping, and the risk of secondary nucleation under constant temperature conditions increases, so that the purity of the final product is usually lower than 99.5%. At the same time, the traditional mechanical stirring system relies on the shaft seal structure to maintain the uniformity of the melt, and the shaft seal wear or leakage problem is prominent in long-term operation. The failure rate of cantilever centrifugal pumps due to dynamic seal failure is more than 30%, and external contaminants (such as lubricating oil, metal debris) in a high-clean environment easily invade through the shaft seal gap, which seriously affects the cleanliness of the product and the service life of the equipment. In addition, the mother liquor separation stage needs to rely on multiple heating-cooling cycles, and the energy consumption increases by 30%-50%, and the yield is only 80%-90%. The above defects show that the existing technology is difficult to meet the production needs of high purity and low energy consumption due to the rigid temperature control, insufficient sealing reliability and low separation efficiency, and breakthroughs are needed in the directions of dynamic temperature control, pollution-free stirring and optimization of crystal purity or yield. SUMMARY

[0003] In order to overcome the defects of the prior art, the utility model provides a high-purity melt crystallization device based on dynamic temperature control and magnetic stirring.

[0004] The utility model discloses a kind of high-purity melt crystallization devices based on dynamic temperature control and magnetic stirring, including crystallizer, the outer of crystallizer is provided with sleeve, the sleeve and the lateral wall of crystallizer form the first temperature adjusting cavity for the circulation of first circulating medium, the lateral wall lower portion of crystallizer is provided with discharge port, the outward end of discharge port penetrates sleeve, the opening of crystallizer is provided with cover, the first thermometer for detecting the temperature of material in crystallizer is installed on the cover, cooling column is installed on the cover, the lower end of cooling column extends into crystallizer, the second temperature adjusting cavity for the circulation of second circulating medium is provided in cooling column, the second thermometer for detecting the temperature of second circulating medium is installed on cooling column, stirring rotor is provided in crystallizer, magnetic stirrer for controlling stirring rotor to agitate material in crystallizer is provided below crystallizer.

[0005] The utility model discloses a kind of high-purity melt crystallization devices based on dynamic temperature control and magnetic stirring, including crystallizer, the outer of crystallizer is provided with sleeve, the sleeve and the lateral wall of crystallizer form the first temperature adjusting cavity for the circulation of first circulating medium, the lateral wall lower portion of crystallizer is provided with discharge port, the outward end of discharge port penetrates sleeve, the opening of crystallizer is provided with cover, the first thermometer for detecting the temperature of material in crystallizer is installed on the cover, cooling column is installed on the cover, the lower end of cooling column extends into crystallizer, the second temperature adjusting cavity for the circulation of second circulating medium is provided in cooling column, the second thermometer for detecting the temperature of second circulating medium is installed on cooling column, stirring rotor is provided in crystallizer, magnetic stirrer for controlling stirring rotor to agitate material in crystallizer is provided below crystallizer.

[0006] As a further improvement of the above-mentioned scheme, a first circulating medium inlet and a first circulating medium outlet are arranged on the side wall of the sleeve body and communicate with the first temperature regulating cavity, and the first temperature regulating cavity is circumscribed by the first temperature control device through the first circulating medium inlet and the first circulating medium outlet.

[0007] As a further improvement of the above-mentioned scheme, a second circulating medium inlet and a second circulating medium outlet are arranged on the side wall of the cooling column and communicate with the second temperature regulating cavity, and the second temperature regulating cavity is circumscribed by the second temperature control device through the second circulating medium inlet and the second circulating medium outlet.

[0008] As a further improvement of the above-mentioned scheme, the second temperature regulating cavity comprises an upper cavity and a lower cavity, the bottom of the upper cavity is provided with an extension pipe extending downward, the lower end of the extension pipe extends into the lower cavity, the upper cavity communicates with the lower cavity through the extension pipe, the second circulating medium outlet is arranged on the side wall of the cooling column corresponding to the upper cavity and communicates with the upper cavity, and the second circulating medium inlet is arranged on the side wall of the cooling column corresponding to the lower cavity and communicates with the lower cavity.

[0009] As a further improvement of the above-mentioned scheme, the part of the discharge port extending out of the side wall of the sleeve body is provided with a discharge valve.

[0010] As a further improvement of the above-mentioned scheme, an outer extension is arranged at the opening of the crystallizer, and the outer extension is fixed with the cover through a clamp.

[0011] As a further improvement of the above-mentioned scheme, a fixing ring is arranged outside the cooling column, fastening bolts are arranged on the fixing ring, the fixing ring is located below the second circulating medium inlet, and the fixing ring is fixedly connected with the cooling column through the fastening bolts.

[0012] The utility model has the beneficial effects that:

[0013] Compared with the prior art,

[0014] The present application realizes the uniformity of the whole temperature field of the molten liquid through the dynamic temperature control cooperative design of the cooling column and the crystallizer, real-time adjustment of the cooling rate and the temperature gradient, and the three-dimensional temperature control structure of the cooling column and the crystallizer.

[0015] Through the pollution-free driving technology of magnetic stirring, the risk of shaft seal wear and pollution (lubricating oil, metal debris) invasion is completely eliminated, and the product purity, yield and production safety of the melting and crystallization process are significantly improved, especially suitable for the industrialized preparation of high-purity materials such as pharmaceutical intermediates and electronic-grade chemicals. BRIEF DESCRIPTION OF DRAWINGS

[0016] Fig. 1 is a structural schematic view of the present utility model;

[0017] Fig. 2 is a structural schematic view of the cooling column in the present utility model.

[0018] In the figure: 1, crystallizer; 101, outer extension; 2, sleeve; 201, first temperature adjusting cavity; 202, first circulating medium inlet; 203, first circulating medium outlet; 3, discharge port; 4, cover; 5, first thermometer; 6, cooling column; 601, second temperature adjusting cavity; 601a, upper cavity; 602b, lower cavity; 602, second circulating medium inlet; 603, second circulating medium outlet; 604, extension pipe; 7, second thermometer; 8, stirring rotor; 9, magnetic stirrer; 10, first temperature control device; 11, second temperature control device; 12, discharge valve; 13, clamp; 14, fixing ring; 15, fastening bolt. DETAILED DESCRIPTION

[0019] In order to further illustrate the technical scheme of the present utility model, the present utility model will be further described below in combination with the drawings and examples.

[0020] As shown in Figs. 1-2 the present utility model provides a kind of high-purity melt crystallization device based on dynamic temperature control and magnetic stirring, including crystallizer 1, sleeve 2 is arranged outside crystallizer 1, sleeve 2 and the side wall of crystallizer 1 form the first temperature adjusting cavity 201 for the first circulating medium circulation flow, the lower part of the side wall of crystallizer 1 is provided with discharge port 3, the outward end of discharge port 3 penetrates sleeve 2, the opening of crystallizer 1 is provided with cover 4, cover 4 is installed with the first thermometer 5 for detecting the temperature of material in crystallizer 1, cover 4 is installed with cooling column 6, the lower end of cooling column 6 extends into crystallizer 1, cooling column 6 is provided with the second temperature adjusting cavity 601 for the second circulating medium circulation flow, cooling column 6 is installed with the second thermometer 7 for detecting the temperature of second circulating medium, and stirring rotor 8 is arranged in crystallizer 1, and magnetic stirrer 9 for controlling stirring rotor 8 to agitate the material in crystallizer 1 is arranged below crystallizer 1.

[0021] Specifically, the temperature of crystallizer and cooling column is accurately adjusted by the first circulating medium (such as water or oil) in the first temperature adjusting cavity 201 and the first circulating medium (such as water or oil) in the second temperature adjusting cavity 601.

[0022] Specifically, the first thermometer 5 and the second thermometer 7 monitor the temperature of key parts in real time to ensure the stability of crystallization process.

[0023] In some examples, the cover 4 is made of polytetrafluoroethylene.

[0024] Further, the side wall of the sleeve body 2 is provided with a first circulating medium inlet 202 and a first circulating medium outlet 203 in communication with the first temperature regulating cavity 201, and the first temperature regulating cavity 201 is circumscribed by the first temperature control device 10 through the first circulating medium inlet 202 and the first circulating medium outlet 203.

[0025] Further, the side wall of the cooling column 6 is configured with a second circulating medium inlet 602 and a second circulating medium outlet 603 in communication with the second temperature regulating cavity 601, and the second temperature regulating cavity 601 is circumscribed by the second temperature control device 11 through the second circulating medium inlet 602 and the second circulating medium outlet 603.

[0026] It should be noted that the first temperature control device 10 and the second temperature control device 11 are devices in the prior art, which have the functions of being able to control the flow of the first circulating medium, being able to detect the temperature of the first circulating medium, and being able to adjust the temperature increase or decrease of the flow of the first circulating medium.

[0027] Further, the second temperature regulating cavity 601 includes an upper cavity 601a and a lower cavity 601b, the bottom of the upper cavity 601a is provided with an extension pipe 604 extending downward, the lower end of the extension pipe 604 extends into the lower cavity 601b, the upper cavity 601a is in communication with the lower cavity 601b through the extension pipe 604, the second circulating medium outlet 603 is arranged on the side wall of the cooling column 6 corresponding to the upper cavity 601a and is in communication with the upper cavity 601a, and the second circulating medium inlet 602 is arranged on the side wall of the cooling column 6 corresponding to the lower cavity 601b and is in communication with the lower cavity 601b, both the second circulating medium inlet 602 and the second circulating medium outlet 603 are located above the cover body 4.

[0028] In some embodiments, the first thermometer 5 can be fixedly installed on the cover body 4 through a threaded thermometer sleeve, and the second thermometer 7 can be fixedly installed on the top of the cooling column 6 through a threaded thermometer sleeve.

[0029] In some embodiments, the second thermometer 7 can also be fixed on the cover body 4 by other means, for example, by winding raw material tape on the surface of the second thermometer 7.

[0030] Further, the part of the discharge port 3 extending out of the side wall of the sleeve body 2 is provided with a discharge valve 12.

[0031] Further, the opening of the crystallizer 1 is configured with an outer extension 101, and the outer extension 101 and the cover body 4 can be fixed by a clamp 13.

[0032] Further, the cooling column 6 is sleeved with a fixing ring 14, the fixing ring 14 is provided with fastening bolts 15, the fixing ring 14 is located below the second circulating medium inlet 602, and the fixing ring 14 is fixedly connected with the cooling column 6 through the fastening bolts 15. The fixing ring 14 is a stainless steel limiting ring, the cooling column 6 is stably arranged on the cover body 4 through cooperation of the fixing ring 14 and the fastening bolts 15, and the cooling column 6 is prevented from sliding downward.

[0033] Specifically, in use, raw materials are added into the crystallizer 1; the raw materials are heated to complete melting through the first circulating medium in the first temperature adjusting cavity 201; the magnetic stirrer 9 is started, and the stirring rotor 8 makes the melt uniform, avoiding local overheating or impurity aggregation; the cooling column 6 is connected with the second circulating medium, and a temperature gradient is formed in the crystallizer 1; the melt is slowly crystallized from the bottom or the surface of the cooling column, and impurities are excluded to the liquid phase; by adjusting the temperature control rate, the crystal layer is gradually grown, and the mother liquor rich in impurities is left in the melt phase; the discharge valve 12 is opened, the melt is discharged first, and then the high-purity crystal is collected.

[0034] Specifically, after the mother liquor is discharged, sweating liquid is discharged during sweating, the purity of the sweating liquid is much higher than that of the mother liquor and slightly lower than that of the melt, the sweating liquid can play a certain flushing effect on the side wall of the crystallizer, and the influence of residual mother liquor on the purity of the product is eliminated.

[0035] Embodiment

[0036] Preparation of electronic-grade p-xylene (purity 99.95%): raw materials are added into the crystallizer 1, the crystallizer 1 is heated to 15℃ (13.2℃ higher than the melting point) through the first circulating medium, and the magnetic stirrer 9 is started; the cooling column 6 is connected with 5℃ second circulating medium (heat-conducting oil), the temperature in the crystallizer is controlled to 10℃ through the first circulating medium, and a crystal layer is formed on the surface of the cooling column 6; the temperature of the cooling column 6 is adjusted to 12.5℃ (slightly lower than the melting point), maintained for 30 minutes, and impurity mother liquor is exuded; the discharge valve 12 is opened to discharge the mother liquor; the temperature of the cooling column 6 is increased to 14℃, and the pure crystal is melted, and the product is collected.

[0037] Effect: the purity of the product reaches 99.97%, the yield is 96%, and the energy consumption is reduced by 40%.

[0038] Specifically, slightly lower than the melting point is -1℃ to -3℃ lower than the melting point of the compound, for example, if the melting point of the compound is 13.2℃, the sweating temperature is set to 10-12.5℃.

[0039] The basic principle and main features of the present application and the advantages of the present application are shown and described above. For those skilled in the art, it is obvious that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or basic characteristics of the present application. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application.

[0040] In addition, it should be understood that, although the present application is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be properly combined to form other embodiments that those skilled in the art can understand.

Claims

1. A high purity melt crystallization device based on dynamic temperature control and magnetic stirring, characterized by: The application relates to a crystallizer (1) provided with a sleeve (2) outside the crystallizer (1), the sleeve (2) and the side wall of the crystallizer (1) form a first temperature adjusting cavity (201) for circulating flow of a first circulating medium, the lower part of the side wall of the crystallizer (1) is provided with a discharge port (3), the outward end of the discharge port (3) penetrates through the sleeve (2), a cover (4) is arranged on the opening of the crystallizer (1), a first thermometer (5) for detecting the temperature of the material in the crystallizer (1) is arranged on the cover (4), a cooling column (6) is arranged on the cover (4), the lower end of the cooling column (6) penetrates into the crystallizer (1), a second temperature adjusting cavity (601) for circulating flow of a second circulating medium is arranged in the cooling column (6), a second thermometer (7) for detecting the temperature of the second circulating medium is arranged on the cooling column (6), a stirring rotor (8) is arranged in the crystallizer (1), and a magnetic stirrer (9) for controlling the stirring of the stirring rotor (8) to the material in the crystallizer (1) is arranged below the crystallizer (1).

2. The high purity melt crystallization device based on dynamic temperature control and magnetic stirring according to claim 1, characterized in that: A first circulating medium inlet (202) and a first circulating medium outlet (203) are arranged on the side wall of the sleeve (2) and communicate with the first temperature adjusting cavity (201), and the first temperature adjusting cavity (201) is externally connected with a first temperature control device (10) through the first circulating medium inlet (202) and the first circulating medium outlet (203).

3. The high purity melt crystallization device based on dynamic temperature control and magnetic stirring of claim 1, wherein: A second circulating medium inlet (602) and a second circulating medium outlet (603) are arranged on the side wall of the cooling column (6) and communicate with the second temperature adjusting cavity (601), and the second temperature adjusting cavity (601) is externally connected with a second temperature control device (11) through the second circulating medium inlet (602) and the second circulating medium outlet (603).

4. The high purity melt crystallization device based on dynamic temperature control and magnetic stirring according to claim 3, characterized in that: The second temperature adjusting cavity (601) comprises an upper cavity (601a) and a lower cavity (601b), the bottom of the upper cavity (601a) is provided with an extension pipe (604) extending downwards, the lower end of the extension pipe (604) extends into the lower cavity (601b), the upper cavity (601a) communicates with the lower cavity (601b) through the extension pipe (604), the second circulating medium outlet (603) is arranged on the side wall of the corresponding cooling column (6) of the upper cavity (601a) and communicates with the upper cavity (601a), the second circulating medium inlet (602) is arranged on the side wall of the corresponding cooling column (6) of the lower cavity (601b) and communicates with the lower cavity (601b), and the second circulating medium inlet (602) and the second circulating medium outlet (603) are both located above the cover (4).

5. The high purity melt crystallization device based on dynamic temperature control and magnetic stirring of claim 1, wherein: The part of the discharge port (3) extending out of the side wall of the sleeve (2) is provided with a discharge valve (12).

6. The high purity melt crystallization device based on dynamic temperature control and magnetic stirring of claim 1, wherein: An outer extension (101) is arranged at the opening of the crystallizer (1), and the outer extension (101) and the cover (4) can be fixed through a clamp (13).

7. The high purity melt crystallization device based on dynamic temperature control and magnetic stirring according to claim 5, characterized in that: The cooling column (6) is sleeved with a fixing ring (14), the fixing ring (14) is provided with a fastening bolt (15), the fixing ring (14) is located below the second circulating medium inlet (602), and the fixing ring (14) is fixedly connected with the cooling column (6) through the fastening bolt (15).

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