Anti-solvent crystallizer and crystallization method

Abstract

The invention discloses an anti-solvent crystallizer and a crystallization method, the anti-solvent crystallizer comprises a crystallizer main body, the crystallizer main body comprises a gradually-shrinking section, a raw material liquid section, a first anti-solvent section and a gradually-expanding section which are communicated in sequence, and flow channels of the gradually-shrinking section, the raw material liquid section, the first anti-solvent section and the gradually-expanding section form a crystallization channel; an annular gap is formed between the reducing section and the raw material liquid section, buffer cavities are formed between the raw material liquid section and the inner wall of the crystallizer main body and between the first anti-solvent section and the inner wall of the crystallizer main body, and a raw material liquid feeding pipe and a first anti-solvent feeding pipe are arranged on the crystallizer main body at intervals; the raw material liquid feeding pipe and the first anti-solvent feeding pipe are respectively communicated with the raw material liquid section and the first anti-solvent section through the buffer cavity. The invention discloses an anti-solvent crystallizer and a crystallization method. The anti-solvent crystallizer and the crystallization method are used for solving the problem that the using effect provided by an existing anti-solvent crystallizer is not ideal.

Description

Technical Field

[0001] The present application relates to the technical field of industrial crystallization, and more specifically, to an anti-solvent crystallizer and a crystallization method. Background Art

[0002] Antisolvent crystallization is a rapid crystallization process. The common antisolvent crystallizer is the kettle crystallizer, which is widely used due to its simple process, convenient operation, and strong applicability. However, the kettle crystallizer is usually operated intermittently, and has the problems of poor mixing effect and long mixing time. Poor mixing effect in the crystallizer will lead to excessive local supersaturation, which may affect the crystal morphology, purity, particle size distribution and other characteristics.

[0003] Therefore, an anti-solvent crystallizer and a crystallization method are needed to solve the above problems. Summary of the invention

[0004] In view of this, the purpose of the present application is to propose an anti-solvent crystallizer and a crystallization method to solve the problem that the use effect provided by the existing anti-solvent crystallizer is not ideal.

[0005] Based on the above purpose, the present application provides an anti-solvent crystallizer, comprising:

[0006] A crystallizer body, the crystallizer body comprising a tapered section, a raw material liquid section, a first anti-solvent section and a gradually expanding section which are connected in sequence, the flow channels of the tapered section, the raw material liquid section, the first anti-solvent section and the gradually expanding section forming a crystallization channel; an annular gap is provided between the tapered section and the raw material liquid section, the raw material liquid section and the first anti-solvent section both have a buffer cavity between them and the inner wall of the crystallizer body, a raw material liquid feed pipe and a first anti-solvent feed pipe are arranged at intervals on the crystallizer body, the raw material liquid feed pipe and the first anti-solvent feed pipe are connected to the raw material liquid section and the first anti-solvent section respectively through the buffer cavity.

[0007] Optionally, the crystallizer body further comprises at least one second anti-solvent segment, which is connected between the first anti-solvent segment and the gradually expanding segment; the flow channel of the second anti-solvent segment is connected with the crystallization channel, and the buffer cavity is provided between the second anti-solvent segment and the inner wall of the crystallizer body; at least one second anti-solvent feed pipe is provided on the crystallizer body, and the second anti-solvent feed pipe is connected with the second anti-solvent segment via the buffer cavity.

[0008] Optionally, at least one supplementary raw material liquid feed pipe is provided on the crystallizer body, and the supplementary raw material liquid feed pipe is connected to the crystallization channel through the first anti-solvent section or the second anti-solvent section.

[0009] Optionally, the crystallizer body comprises a convergent pipe, a first shell, a second shell, a third shell and a divergent pipe connected in sequence, and a raw material liquid sleeve, a first anti-solvent sleeve and a second anti-solvent sleeve are sequentially arranged in the first shell, the second shell and the third shell;

[0010] The convergent tube and the divergent tube form the convergent section and the divergent section respectively; the first shell and the raw material liquid sleeve form the raw material liquid section; the second shell and the first anti-solvent feed pipe form the first anti-solvent section; the third shell and the second anti-solvent feed pipe form the second anti-solvent section;

[0011] The raw material liquid feed pipe, the first anti-solvent feed pipe, the supplementary raw material liquid feed pipe and the second anti-solvent feed pipe are respectively arranged on at least one of the first shell, the second shell and the third shell.

[0012] Optionally, the buffer chamber includes a first buffer chamber arranged in a first shell, the raw material liquid sleeve is at least partially arranged in the first buffer chamber, at least one feed hole is arranged on the raw material liquid sleeve, an annular gap is arranged between the raw material liquid sleeve and the tapered tube, the raw material liquid feed pipe is arranged on the first shell, and the raw material liquid feed pipe is connected to the crystallization channel through the first buffer chamber, the feed hole and the annular gap.

[0013] Optionally, the inlet end of the raw liquid sleeve includes a connecting pipe section and an inlet pipe section that are connected in sequence, the connecting pipe section is sleeved outside the reducer, the annular gap is formed between the connecting pipe section and the reducer, and the feed hole is arranged on the connecting pipe section; the inner diameter of the inlet pipe section is smaller than the inner diameter of the reducer.

[0014] Optionally, a plurality of protrusions spaced apart along the axial direction are provided in the raw material liquid sleeve, and the protrusions are used to reduce the passing area of ​​the raw material liquid sleeve.

[0015] Optionally, the buffer chamber includes a second buffer chamber arranged in a second shell, the first anti-solvent sleeve is at least partially arranged in the second buffer chamber, the first anti-solvent sleeve is provided with at least one first dispersion hole, the first anti-solvent feed pipe is arranged on the second shell, and the first anti-solvent feed pipe is connected to the crystallization channel through the second buffer chamber and the first dispersion hole.

[0016] Optionally, the buffer chamber includes a third buffer chamber arranged in a third shell, the first anti-solvent sleeve is at least partially arranged in the third buffer chamber, the first anti-solvent sleeve is provided with at least one second dispersion hole, the supplementary raw material liquid feed pipe is arranged on the third shell, and the supplementary raw material liquid feed pipe is connected to the crystallization channel through the third buffer chamber and the second dispersion hole.

[0017] Optionally, the buffer chamber includes a fourth buffer chamber arranged in a third shell, the second anti-solvent sleeve is at least partially arranged in the fourth buffer chamber, the second anti-solvent sleeve is provided with at least one third dispersion hole, the second anti-solvent sleeve is arranged on the third shell, and the second anti-solvent sleeve is connected to the crystallization channel through the fourth buffer chamber and the third dispersion hole.

[0018] Optionally, at least one guide plate is disposed in the second anti-solvent sleeve.

[0019] The present application also provides a crystallization method using the anti-solvent crystallizer as described above, comprising:

[0020] (1) The raw material liquid enters the raw material liquid section from the raw material liquid feed pipe through the buffer chamber, the anti-solvent enters the raw material liquid section from the tapered section through the annular gap and mixes with the raw material liquid, and crystals are precipitated in the crystallization channel to form a mixed fluid;

[0021] (2) The mixed fluid enters the first anti-solvent section, the anti-solvent enters the first anti-solvent section from the first anti-solvent feed pipe through the buffer chamber to mix with the mixed fluid, crystals precipitate in the crystallization channel, and are discharged from the gradually expanding section.

[0022] Optionally, the crystallizer body further comprises at least one second anti-solvent section, and at least one second anti-solvent feed pipe is provided on the crystallizer body, and step (2) further comprises: the mixed fluid of the first anti-solvent section enters the second anti-solvent section, the anti-solvent enters the second anti-solvent section from the second anti-solvent feed pipe through the buffer chamber to mix with the mixed fluid, and crystals are precipitated from the crystallization channel.

[0023] Optionally, at least one feed pipe for replenishing raw material liquid is provided on the crystallizer body, and step (2) further comprises: the feed pipe for replenishing raw material liquid to the crystallization channel through the first anti-solvent section or the second anti-solvent section.

[0024] Optionally, the crystallizer body comprises a convergent pipe, a first shell, a second shell, a third shell and a divergent pipe connected in sequence; a raw material liquid sleeve, a first anti-solvent sleeve and a second anti-solvent sleeve are arranged in sequence in the first shell, the second shell and the third shell;

[0025] Step (1) comprises: the raw material liquid enters the raw material liquid casing from the raw material liquid feed pipe, and the anti-solvent enters the raw material liquid casing from the reducer pipe to mix with the raw material liquid;

[0026] Step (2) includes: the mixed fluid enters the first anti-solvent sleeve, the anti-solvent enters the first anti-solvent sleeve from the first anti-solvent feed pipe and mixes with the mixed fluid, crystals are precipitated in the crystallization channel, and a mixed fluid with increased concentration is formed; the supplementary raw material liquid feed pipe supplements the raw material liquid to the crystallization channel through the first anti-solvent sleeve or the second anti-solvent sleeve; the mixed fluid with increased concentration and the supplementary raw material liquid enter the second anti-solvent sleeve, the anti-solvent enters the second anti-solvent sleeve from the second anti-solvent feed pipe and mixes with the mixed fluid with increased concentration and the supplementary raw material liquid, and crystals are precipitated in the crystallization channel.

[0027] Optionally, the buffer chamber includes a first buffer chamber arranged in a first shell, the raw material liquid sleeve is at least partially arranged in the first buffer chamber, at least one feed hole is arranged on the raw material liquid sleeve, an annular gap is arranged between the raw material liquid sleeve and the tapered tube, and the raw material liquid feed pipe is arranged on the first shell; step (1) also includes: the raw material liquid passes through the raw material liquid feed pipe, the first buffer chamber, the feed hole and the annular gap in sequence into the crystallization channel.

[0028] Optionally, the buffer chamber includes a second buffer chamber arranged in a second shell, the first anti-solvent sleeve is at least partially arranged in the second buffer chamber, the first anti-solvent sleeve is provided with at least one first dispersion hole, and the first anti-solvent feed pipe is arranged on the second shell; step (2) also includes: the anti-solvent passes through the first anti-solvent feed pipe, the second buffer chamber and the first dispersion hole in sequence into the crystallization channel.

[0029] Optionally, the buffer chamber includes a third buffer chamber arranged in a third shell, the first anti-solvent sleeve is at least partially arranged in the third buffer chamber, the first anti-solvent sleeve is provided with at least one second dispersion hole, and the supplementary raw material liquid feed pipe is arranged on the third shell; step (2) also includes: the supplementary raw material liquid passes through the supplementary raw material liquid feed pipe, the third buffer chamber and the second dispersion hole in sequence into the crystallization channel.

[0030] Optionally, the buffer chamber includes a fourth buffer chamber arranged in a third shell, the second anti-solvent sleeve is at least partially arranged in the fourth buffer chamber, the second anti-solvent sleeve is provided with at least one third dispersion hole, and the second anti-solvent sleeve is arranged on the third shell; step (2) also includes: the anti-solvent enters the crystallization channel through the second anti-solvent sleeve, the fourth buffer chamber and the third dispersion hole in sequence.

[0031] Optionally, step (2) further comprises: changing the crystal shape and particle size by adjusting the relative feed rate of the raw material liquid and the anti-solvent; and / or changing the crystal shape and particle size by adjusting the feed flow pattern of the first anti-solvent sleeve and the second anti-solvent sleeve.

[0032] Optionally, step (2) also includes: increasing the feed rate of at least one of the tapered tube, the first anti-solvent feed tube, and the second anti-solvent sleeve, and / or reducing the feed rate of the raw material liquid feed tube; and using the first dispersion hole as the radial feeding direction of the first anti-solvent sleeve and the second anti-solvent sleeve to feed to obtain fibrous precipitated crystals.

[0033] Optionally, step (2) also includes: reducing the feed rate of at least one of the tapered tube, the first anti-solvent feed tube, and the second anti-solvent sleeve, and / or increasing the feed rate of the raw material liquid feed tube; and using the first anti-solvent sleeve and the second anti-solvent sleeve to feed with the second dispersion hole as the tangential feed direction, and the supplementary raw material liquid feed pipe provides supplementary raw material liquid to obtain spherical precipitated crystals.

[0034] As can be seen from the above, the anti-solvent crystallizer and crystallization method provided by the present application have the following advantages compared with the prior art: using the above-mentioned anti-solvent crystallizer, the buffer chamber provides a buffering effect for the raw material liquid and the anti-solvent entering the crystallization channel; the anti-solvent enters the crystallization channel from the tapered section and the first anti-solvent section respectively, and by setting up multiple entries into the anti-solvent, a controllable solute supersaturation gradient can be formed in the crystallization channel; the annular gap is conducive to the anti-solvent fluid shearing off the raw material liquid, so that the raw material liquid entering the clean channel is in a dispersed phase, the raw material liquid and the anti-solvent can be fully mixed in a short time, and the mixing between the fluids in the channel is strengthened, thereby obtaining a product with controllable crystal particle size and shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The above-mentioned features and technical advantages of the present application will become clearer and easier to understand through the following description of its embodiments in conjunction with the accompanying drawings.

[0036] Figure 1 Schematic diagram of the anti-solvent crystallizer used in the specific embodiments of the present application.

[0037] Figure 2 for Figure 1 An exploded view of the antisolvent crystallizer is shown.

[0038] Figure 3 for Figure 1 Schematic diagram of the feed solution casing of the anti-solvent crystallizer is shown.

[0039] Figure 4 for Figure 1A schematic diagram of the first anti-solvent sleeve of the anti-solvent crystallizer is shown.

[0040] Figure 5 Schematic diagram of the first anti-solvent sleeve of the anti-solvent crystallizer used in another embodiment.

[0041] Figure 6 for Figure 1 A schematic diagram of the second anti-solvent sleeve of the anti-solvent crystallizer is shown.

[0042] The reference numerals are:

[0043] 1. Gradually converging tube; 2. Feed hole; 3. Raw material liquid feed pipe; 4. Raw material liquid sleeve; 41. Connecting pipe section; 42. Inlet pipe section; 5. Second shell; 6. First anti-solvent feed pipe; 7. First anti-solvent sleeve; 8. Supplementary raw material liquid feed pipe; 9. Third shell; 10. Second anti-solvent feed pipe; 11. Second anti-solvent sleeve; 12. Gradually expanding tube; 14. First shell; 15. Protrusion; 16. First dispersion hole; 16-1. Tangential dispersion hole; 16-1. Radial dispersion hole; 17. Second dispersion hole; 18. Third dispersion hole; 19. Guide plate; 20. Gradually expanding hole. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings. The same parts are represented by the same figure numerals. It should be noted that the words "front", "rear", "left", "right", "up" and "down" used in the following description refer to the directions in the accompanying drawings. The words "inside" and "outside" used refer to the direction toward or away from the geometric center of a specific component, respectively.

[0045] Figure 1 Schematic diagram of the anti-solvent crystallizer used in the specific embodiments of the present application. Figure 2 for Figure 1 Exploded view of the antisolvent crystallizer shown. Figure 1 and Figure 2 As shown, the anti-solvent crystallizer includes a crystallizer body.

[0046] The main body of the crystallizer includes a tapered section, a raw material liquid section, a first anti-solvent section and a gradually expanding section which are connected in sequence. The flow channels of the tapered section, the raw material liquid section, the first anti-solvent section and the gradually expanding section form a crystallization channel. An annular gap is arranged between the tapered section and the raw material liquid section. Both the raw material liquid section and the first anti-solvent section have a buffer cavity with the inner wall of the main body of the crystallizer. A raw material liquid feed pipe 3 and a first anti-solvent feed pipe 6 are arranged at intervals on the main body of the crystallizer. The raw material liquid feed pipe 3 and the first anti-solvent feed pipe 6 are connected to the raw material liquid section and the first anti-solvent section respectively through the buffer cavity.

[0047] The raw material liquid enters the raw material liquid section from the raw material liquid inlet pipe 3 through the buffer cavity and the annular gap, and the anti-solvent enters the channel of the raw material liquid section from the flow channel of the gradually contracting section to mix with the raw material liquid to complete the precipitation process; after the mixed fluid enters the channel in the first anti-solvent section, it mixes with the anti-solvent entering from the first anti-solvent feed pipe 6 through the buffer cavity, further increasing the solute supersaturation, so that the internal solvent of the crystals obtained by precipitation is precipitated and discharged from the gradually expanding section.

[0048] By adopting the above-mentioned anti-solvent crystallizer, the buffer chamber provides a buffering effect for the raw material liquid and the anti-solvent to enter the crystallization channel; the anti-solvent enters the crystallization channel from the tapered section and the first anti-solvent section respectively, and by arranging multiple entries into the anti-solvent, a controllable solute supersaturation gradient can be formed in the crystallization channel; the annular gap is conducive to the anti-solvent fluid shearing off the raw material liquid, so that the raw material liquid entering the clean channel is in a dispersed phase, the raw material liquid and the anti-solvent can be fully mixed in a short time, and the mixing between the fluids in the channel is strengthened, thereby obtaining a product with controllable crystal particle size and shape.

[0049] Optionally, the crystallizer body also includes at least one second anti-solvent section, the second anti-solvent section is connected between the first anti-solvent section and the gradually expanding section, the flow channel of the second anti-solvent section is connected to the crystallization channel, and a buffer cavity is provided between the second anti-solvent section and the inner wall of the crystallizer body; at least one second anti-solvent feed pipe 10 is provided on the crystallizer body, and the second anti-solvent feed pipe 10 is connected to the second anti-solvent section through the buffer cavity. The mixed fluid of the first anti-solvent section enters the second anti-solvent section axially, mixes with the anti-solvent entering through the buffer cavity from the second anti-solvent feed pipe 10, and further increases the solute supersaturation, so that the solvent wrapped in the crystal is completely precipitated. At least two groups of anti-solvent feeds are provided, and a controllable solute supersaturation gradient can be formed in the crystallization channel by arranging multiple entries of the anti-solvent.

[0050] Optionally, at least one supplementary raw material feed pipe 8 is provided on the crystallizer body, and the supplementary raw material feed pipe 8 is connected to the crystallization channel through the first anti-solvent section or the second anti-solvent section. The supplementary raw material feed pipe 8 is arranged between the first anti-solvent section and the second anti-solvent section, and the supplementary raw material liquid enters the first anti-solvent section and the second anti-solvent section through the buffer chamber from the supplementary raw material feed pipe 8. At least two groups of raw material liquid are fed, and by arranging multiple times to enter the raw material liquid, a controllable solute supersaturation gradient can be formed in the crystallization channel.

[0051] Optionally, the crystallizer body includes a convergent tube 1, a first shell 14, a second shell 5, a third shell 9 and a divergent tube 12 connected in sequence, and the first shell 14, the second shell 5 and the third shell 9 are provided with a raw material liquid sleeve 4, a first anti-solvent sleeve 7 and a second anti-solvent sleeve 11 in sequence; the convergent tube 1 and the divergent tube 12 form a convergent section and a divergent section respectively; the first shell 14 and the raw material liquid sleeve 4 form a raw material liquid section; the second shell 5 and the first anti-solvent feed pipe 6 form a first anti-solvent section; the third shell 9 and the second anti-solvent feed pipe 10 form a second anti-solvent section; the raw material liquid feed pipe 3, the first anti-solvent feed pipe 6, the supplementary raw material feed pipe 8 and the second anti-solvent feed pipe 10 are respectively provided on at least one of the first shell 14, the second shell 5 and the third shell 9. The anti-solvent crystallizer has a Venturi structure, and is provided with multiple entry of the raw material liquid and the anti-solvent. When the anti-solvent / raw material liquid ratio is small, the suction effect of the Venturi structure is utilized, and the pumping system is no longer required, thereby simplifying the structure. The raw material liquid or anti-solvent is first dispersed in the buffer chamber and then enters the crystallization channel, which effectively avoids the appearance of block crystals caused by local high concentration in the crystallization channel.

[0052] In one embodiment of the present application, the structures adjacent to each other, such as the reducer 1, the first shell 14, the raw material liquid sleeve 4, the second shell 5, the first anti-solvent sleeve 7, the third shell 9, the second anti-solvent sleeve 11, and the gradually expanding tube 12, can be fixedly connected or detachably connected, such as the reducer 1 and the first shell 14 are snap-connected, and the raw material liquid sleeve 4 is snap-connected with the first shell 14 and the second shell 5. The raw material liquid feed pipe 3 is arranged on the first shell 14, the first anti-solvent feed pipe 6 is arranged on the second shell 5, and the supplementary raw material feed pipe 8 and the second anti-solvent feed pipe 10 are respectively arranged on the third shell 9.

[0053] In one embodiment of the present application, the flow channel in the reducer 1 includes a reducer section and a straight section that are connected in sequence, the reducer section is used for feeding, and the straight section is used for discharging.

[0054] In one embodiment of the present application, the flow channel in the gradually expanding tube 12 includes a straight section and a gradually expanding section connected in sequence, the straight section is used for feeding, and the gradually expanding section (ie, the gradually expanding hole 20) is used for discharging.

[0055] In one embodiment of the present application, the raw material solution sleeve 4 is in a stepped shape, the first anti-solvent sleeve 7 is approximately in a cross shape, and the second anti-solvent sleeve 11 is approximately in a cross shape.

[0056] Figure 3 for Figure 1 Schematic diagram of the feedstock casing of the anti-solvent crystallizer shown in FIG. Figure 3 As shown, the anti-solvent crystallizer includes a raw liquid casing 4.

[0057] Optionally, the buffer chamber includes a first buffer chamber arranged in the first shell 14, the raw material liquid sleeve 4 is at least partially arranged in the first buffer chamber, at least one feed hole 2 is arranged on the raw material liquid sleeve 4, an annular gap is arranged between the raw material liquid sleeve 4 and the tapered tube 1, and the raw material liquid feed pipe 3 is arranged on the first shell 14, and the raw material liquid feed pipe 3 is connected to the crystallization channel through the first buffer chamber, the feed hole 2 and the annular gap. The raw material liquid first enters the first buffer chamber composed of the raw material liquid sleeve 4 and the first shell 14 through the raw material liquid feed pipe 3, enters the crystallization channel through the annular gap composed of the tapered tube 1 and the raw material liquid sleeve 4 through the circumferentially arranged feed hole 2, and mixes with the anti-solvent entering from the tapered tube 1 in a very short time to complete the precipitation process. With the above-mentioned raw material liquid sleeve 4 structure, the first buffer chamber can provide a buffering effect, and the annular gap is conducive to the anti-solvent fluid shearing the raw material liquid, so that the raw material liquid entering the flow channel is in a dispersed phase, and the raw material liquid and the anti-solvent can be fully mixed in a short time.

[0058] In one embodiment of the present application, the reducer 1, the first shell 14 and the second shell 5 are snap-connected in sequence, the reducer 1 partially extends into the first shell 14, and the opposite ends of the raw liquid sleeve 4 are respectively located in the first shell 14 and the second shell 5.

[0059] In one embodiment of the present application, the feed holes 2 extend along the radial direction of the raw material liquid sleeve 4 , and the plurality of feed holes 2 are evenly distributed in the circumferential direction of the raw material liquid sleeve 4 .

[0060] Optionally, the inlet end of the raw material liquid sleeve 4 includes a connecting pipe section 41 and an inlet pipe section 42 that are connected in sequence, the connecting pipe section 41 is sleeved outside the reducer 1, an annular gap is formed between the connecting pipe section 41 and the reducer 1, and the feed hole 2 is arranged on the connecting pipe section 41; the inner diameter of the inlet pipe section 42 is smaller than the inner diameter of the reducer 1. The channel diameter of the connecting pipe section 41 is larger than the diameter of the straight section of the reducer 1, and the channel diameter of the inlet pipe section 42 is smaller than the diameter of the straight section of the reducer 1. The annular gap formed has a stepped shape, and the annular gap is generally 1-3mm. The annular gap is conducive to the anti-solvent fluid shearing off the raw material liquid, so that the raw material liquid entering the flow channel is in a dispersed phase. With the above-mentioned raw material liquid sleeve 4, under the action of the annular gap, the raw material liquid and the anti-solvent can be fully mixed in the raw material liquid sleeve 4.

[0061] Optionally, a plurality of protrusions 15 spaced apart along the axial direction are provided in the raw liquid sleeve 4, and the protrusions 15 are used to reduce the passing area of ​​the raw liquid sleeve 4. With the raw liquid sleeve 4 having the protrusions 15, the protrusions 15 increase the turbulence in the crystallization channel and help to fully mix.

[0062] In one embodiment of the present application, the protrusion 15 protrudes toward the flow channel of the raw liquid sleeve 4, and the protrusion 15 is distributed in an array on the raw liquid sleeve 4. A plurality of protrusions 15 are evenly distributed in the circumferential direction of the raw liquid sleeve 4, and a plurality of protrusions 15 are spaced apart along the axial direction of the raw liquid sleeve 4. The protrusion 15 is a circumferential semicircular structure, and the height of the protrusion 15 is 1 / 5 of the inner diameter of the crystallization channel, and the spacing between two circles of protrusions 15 is one times the inner diameter of the crystallization channel.

[0063] Figure 4 for Figure 1 Schematic diagram of the first anti-solvent sleeve of the anti-solvent crystallizer shown. Figure 4 As shown, the anti-solvent crystallizer includes a first anti-solvent sleeve 7.

[0064] Optionally, the buffer chamber includes a second buffer chamber arranged in the second shell 5, the first anti-solvent sleeve 7 is at least partially arranged in the second buffer chamber, the first anti-solvent sleeve 7 is provided with at least one first dispersion hole 16, the first anti-solvent feed pipe 6 is arranged on the second shell 5, and the first anti-solvent feed pipe 6 is connected to the crystallization channel through the second buffer chamber and the first dispersion hole 16. The anti-solvent enters the second buffer chamber composed of the second shell 5 and the first anti-solvent sleeve 7 through the first anti-solvent feed pipe 6, and enters the crystallization channel through the first dispersion holes 16 arranged circumferentially; as the anti-solvent enters through the first dispersion hole 16, the supersaturation of the solute in the axial direction increases. With the above-mentioned first anti-solvent sleeve 7, the second buffer chamber can provide a buffering effect, and the mixed fluid and the anti-solvent can be fully mixed in a short time.

[0065] In one embodiment of the present application, the first shell 14 , the second shell 5 and the third shell 9 are snap-connected in sequence, and the opposite ends of the first anti-solvent sleeve 7 are respectively located in the second shell 5 and the third shell 9 .

[0066] The first dispersion holes 16 have two feeding directions, tangential and radial. The first anti-solvent sleeve 7 can be replaced according to the different particle properties required by the process; in one embodiment of the present application, the first dispersion holes 16 extend along the tangential direction of the first anti-solvent sleeve 7, that is, the tangential dispersion holes 16-1, and the first dispersion holes 16 are distributed in an array on the first anti-solvent sleeve 7. A plurality of first dispersion holes 16 are evenly distributed in the circumferential direction of the first anti-solvent sleeve 7, and the plurality of first dispersion holes 16 are distributed at intervals along the axial direction of the first anti-solvent sleeve 7. For example, the first dispersion holes 16 are arranged along the circumference of the first anti-solvent sleeve 7, and three layers are arranged in the axial direction. The diameter of the first dispersion holes 16 is 0.5-2 mm, and the number of the first dispersion holes 16 in each layer is 7-12.

[0067] Figure 5 FIG. 4 is a schematic diagram of a first anti-solvent sleeve of an anti-solvent crystallizer used in another embodiment. Figure 5As shown, in another embodiment of the present application, the first dispersion holes 16 extend along the radial direction of the first anti-solvent sleeve 7, namely radial dispersion holes 16-2. The remaining configurations may refer to the above embodiments and will not be described again.

[0068] Optionally, the buffer chamber includes a third buffer chamber disposed in the third shell 9, the first anti-solvent sleeve 7 is at least partially disposed in the third buffer chamber, the first anti-solvent sleeve 7 is provided with at least one second dispersion hole 17, and the supplementary raw material feed pipe 8 is disposed on the third shell 9, and the supplementary raw material feed pipe 8 is connected with the crystallization channel through the third buffer chamber and the second dispersion hole 17. The supplementary raw material liquid enters the third buffer chamber composed of the first anti-solvent sleeve 7 and the third shell 9 through the supplementary raw material feed pipe 8, and enters the crystallization channel through the second dispersion hole 17; the above-mentioned supplementary raw material feed pipe 8 is used to provide the supplementary raw material liquid, and the third buffer chamber can provide a buffering effect, so that the raw material liquid and the anti-solvent can be fully mixed in a short time.

[0069] In one embodiment of the present application, relatively distributed partitions are provided in the third shell 9, the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11 are connected between the partitions, a third buffer chamber is between the first anti-solvent sleeve 7 and the partition, and a fourth buffer chamber is between the second anti-solvent sleeve 11 and the partition.

[0070] In one embodiment of the present application, the second dispersed holes 17 extend along the tangential direction of the first anti-solvent sleeve 7, and the plurality of second dispersed holes 17 are evenly distributed in the circumferential direction of the first anti-solvent sleeve 7. For example, the diameter of the second dispersed holes 17 is 0.25-1 mm, and the number of the second dispersed holes 17 in each layer is 7-12.

[0071] In another embodiment of the present application, the second dispersion holes 17 extend along the radial direction of the first anti-solvent sleeve 7, and the remaining configurations may refer to the above embodiments and will not be described in detail herein.

[0072] Figure 6 for Figure 1 Schematic diagram of the second anti-solvent sleeve of the anti-solvent crystallizer shown. Figure 6As shown, the anti-solvent crystallizer includes a second anti-solvent sleeve 11. Optionally, the buffer chamber includes a fourth buffer chamber arranged in the third shell 9, the second anti-solvent sleeve 11 is at least partially arranged in the fourth buffer chamber, the second anti-solvent sleeve 11 is provided with at least one third dispersion hole 18, the second anti-solvent sleeve 11 is arranged on the third shell 9, and the second anti-solvent sleeve 11 is connected to the crystallization channel through the fourth buffer chamber and the third dispersion hole 18. The anti-solvent enters the fourth buffer chamber composed of the third shell 9 and the second anti-solvent sleeve 11 through the second anti-solvent feed pipe 10, and enters the crystallization channel through the third dispersion hole 18 arranged circumferentially; as the anti-solvent enters through the third dispersion hole 18, the supersaturation of the solute in the axial direction increases. With the above-mentioned second anti-solvent sleeve 11, the fourth buffer chamber can provide a buffering effect, and the mixed fluid and the anti-solvent can be fully mixed in a short time.

[0073] In one embodiment of the present application, the first shell 14 , the second shell 5 and the third shell 9 are sequentially snap-connected, and opposite ends of the second anti-solvent sleeve 11 are respectively located in the third shell 9 and the diffuser tube 12 .

[0074] The third dispersion holes 18 have two feeding directions, tangential and radial. The second anti-solvent sleeve 11 can be replaced according to the different particle properties required by the process; in one embodiment of the present application, the third dispersion holes 18 extend along the tangential direction of the second anti-solvent sleeve 11, and the third dispersion holes 18 are distributed in an array on the second anti-solvent sleeve 11. A plurality of third dispersion holes 18 are evenly distributed in the circumferential direction of the second anti-solvent sleeve 11, and the plurality of third dispersion holes 18 are distributed at intervals along the axial direction of the second anti-solvent sleeve 11. For example, the third dispersion holes 18 are arranged along the circumference of the second anti-solvent sleeve 11, and three layers are provided in the axial direction. The diameter of the third dispersion holes 18 is 0.5-2 mm, and the number of third dispersion holes 18 in each layer is 7-12.

[0075] In another embodiment of the present application, the third dispersion holes 18 extend along the radial direction of the second anti-solvent sleeve 11 , and other configurations may refer to the above embodiments and will not be described in detail herein.

[0076] Optionally, at least one guide plate 19 is disposed in the second anti-solvent sleeve 11. Through the guiding effect of the guide plate 19, the flow direction of the fluid is changed from tangential flow to axial flow.

[0077] In one embodiment of the present application, there are multiple guide plates 19, and the multiple guide plates 19 are evenly distributed along the circumferential direction of the second anti-solvent sleeve 11, and the guide plates 19 extend along the axial direction of the second anti-solvent sleeve 11. The height of the guide plate 19 is 1 / 10 of the channel diameter of the second anti-solvent sleeve 11.

[0078] The use of the anti-solvent crystallizer is further described below.

[0079] Example 1: The convergent tube 1, the raw material liquid sleeve 4, the first anti-solvent sleeve 7, the second anti-solvent sleeve 11 and the divergent tube 12 are connected in sequence to form a Venturi tube-shaped crystallization channel structure; the anti-solvent enters the crystallization channel from the convergent tube 1, the first anti-solvent feed pipe 6, and the second anti-solvent feed pipe 10 respectively, and the raw material liquid enters the crystallization channel from the raw material liquid feed pipe 3 and the supplementary raw material feed pipe 8 respectively.

[0080] Example 2: Potassium bicarbonate powder is prepared by using an anti-solvent crystallizer, anhydrous ethanol at room temperature is used as the anti-solvent, and potassium bicarbonate aqueous solution is used as the raw material liquid. Potassium bicarbonate is insoluble in anhydrous ethanol, but water and anhydrous ethanol are mutually soluble, and potassium bicarbonate crystals are precipitated. The inlet diameter of the tapered tube 1 is 74mm, the inner diameter of the crystallization channel is 24mm, the annular gap is 2mm, the first dispersion hole 16 and the third dispersion hole 18 adopt radial flow direction, the pore diameter is 2mm, and there is no need to use supplementary raw material liquid feeding. The inlet anti-solvent flow rate of the tapered tube 1 is 200L / h, and the anti-solvent flow rate of the first anti-solvent feed pipe 6 and the second anti-solvent feed pipe 10 is 50L / h. When crystallization starts, the anti-solvent is first introduced until the inside is smooth and stable. The flow rate of the raw material liquid is 20L / h. After entering the annular gap from the raw material liquid feed pipe 3, it enters the crystallization channel through the liquid inlet to complete the precipitation process. After passing through the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11 with the mixed fluid, it is discharged from the gradually expanding tube 12 and stored in the buffer tank. Potassium bicarbonate crystals are obtained by filtration, and the particle size range is 10μm to 23μm, and d50=17μm.

[0081] Example 3: Sodium chloride powder is prepared by using an anti-solvent crystallizer, with anhydrous ethanol as the anti-solvent at room temperature and sodium chloride solution as the raw material liquid. Sodium chloride is insoluble in anhydrous ethanol, but water and anhydrous ethanol are mutually soluble, and sodium chloride crystals are precipitated. The inlet diameter of the tapered tube 1 is 74mm, the inner diameter of the crystallization channel is 24mm, the annular gap is 2mm, the first dispersion hole 16 (using the tangential dispersion hole 16-1) and the third dispersion hole 18, the pore size is 2mm, and there is no need to use supplementary raw material liquid feeding. The inlet anti-solvent flow rate of the tapered tube 1 is 300L / h, and the anti-solvent flow rate of the first anti-solvent feed pipe 6 and the second anti-solvent feed pipe 10 is 70L / h. When crystallization starts, the anti-solvent is first added until the inside is smooth and stable. The flow rate of the raw material liquid is 30L / h. After entering the annular gap from the raw material liquid feed pipe 3, it enters the crystallization channel through the liquid inlet to complete the precipitation process. After passing through the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11 with the mixed fluid, it is discharged from the gradually expanding tube 12 and stored in the buffer tank. Spherical sodium chloride crystals are obtained by filtration, and the particle size range is 9μm~15μm, d50=12μm. Subsequently, 3L / h raw material liquid is added from the supplementary raw material liquid feed pipe 8, and the second dispersion hole 17 enters the crystallization channel to complete the precipitation process. After passing through the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11 with the mixed fluid, it is discharged from the gradually expanding tube 12 and stored in the buffer tank. Spherical sodium chloride crystals are obtained by filtration, and the particle size range is 12μm~22μm, d50=17μm.

[0082] The present application also provides a crystallization method using the anti-solvent crystallizer as described above, comprising:

[0083] (1) The raw material liquid enters the raw material liquid section from the raw material liquid feed pipe 3 through the buffer chamber, the anti-solvent enters the raw material liquid section from the tapered section through the annular gap and mixes with the raw material liquid, and crystals are precipitated in the crystallization channel to form a mixed fluid;

[0084] (2) The mixed fluid enters the first anti-solvent section, and the anti-solvent enters the first anti-solvent section from the first anti-solvent feed pipe 6 through the buffer chamber to mix with the mixed fluid, and crystals precipitate in the crystallization channel and are discharged from the gradually expanding section.

[0085] The raw material liquid enters the raw material liquid section from the raw material liquid inlet pipe 3 through the buffer cavity and the annular gap, and the anti-solvent enters the channel of the raw material liquid section from the flow channel of the gradually contracting section to mix with the raw material liquid to complete the precipitation process; after the mixed fluid enters the channel in the first anti-solvent section, it mixes with the anti-solvent entering from the first anti-solvent feed pipe 6 through the buffer cavity, further increasing the solute supersaturation, so that the internal solvent of the crystals obtained by precipitation is precipitated and discharged from the gradually expanding section.

[0086] The crystallization method using the anti-solvent crystallizer is adopted, and the buffer chamber provides a buffering effect for the raw material liquid and the anti-solvent to enter the crystallization channel; the anti-solvent enters the crystallization channel from the tapered section and the first anti-solvent section respectively, and a controllable solute supersaturation gradient can be formed in the crystallization channel by arranging multiple entries of the anti-solvent; the annular gap is conducive to the anti-solvent fluid shearing off the raw material liquid, so that the raw material liquid entering the clean channel is in a dispersed phase, the raw material liquid and the anti-solvent can be fully mixed in a short time, and the mixing between the fluids in the channel is strengthened, thereby obtaining a product with controllable crystal particle size and shape.

[0087] By adopting multi-stage anti-solvent feeding, suction can be used to feed, and a pumping system is no longer required. Optionally, the crystallizer body also includes at least one second anti-solvent section, and at least one second anti-solvent feed pipe 10 is provided on the crystallizer body. Step (2) also includes: the mixed fluid of the first anti-solvent section enters the second anti-solvent section, the anti-solvent enters the second anti-solvent section through the buffer chamber from the second anti-solvent feed pipe 10 and mixes with the mixed fluid, and crystals are precipitated in the crystallization channel.

[0088] The crystallization setting can be adjusted by feeding the supplementary raw material liquid. Optionally, at least one supplementary raw material feed pipe 8 is provided on the crystallizer body. Step (2) also includes: the supplementary raw material feed pipe 8 supplements the raw material liquid to the crystallization channel through the first anti-solvent section or the second anti-solvent section.

[0089] In order to achieve a smooth crystallization process and produce crystals of different shapes and particle sizes, optionally, the crystallizer body includes a convergent tube 1, a first shell 14, a second shell 5, a third shell 9 and a divergent tube 12 connected in sequence; the first shell 14, the second shell 5 and the third shell 9 are sequentially provided with a raw liquid sleeve 4, a first anti-solvent sleeve 7 and a second anti-solvent sleeve 11;

[0090] Step (1) comprises: the raw material liquid enters the raw material liquid casing 4 from the raw material liquid feed pipe 3, and the anti-solvent enters the raw material liquid casing 4 from the tapered pipe 1 to mix with the raw material liquid;

[0091] Step (2) includes: the mixed fluid enters the first anti-solvent sleeve 7, the anti-solvent enters the first anti-solvent sleeve 7 from the first anti-solvent feed pipe 6 to mix with the mixed fluid, crystals are precipitated in the crystallization channel, and a mixed fluid with increased concentration is formed; the supplementary raw material feed pipe 8 supplements the raw material liquid to the crystallization channel through the first anti-solvent sleeve 7 or the second anti-solvent sleeve 11; the mixed fluid with increased concentration and the supplementary raw material liquid enter the second anti-solvent sleeve 11, the anti-solvent enters the second anti-solvent sleeve 11 from the second anti-solvent feed pipe 10 to mix with the mixed fluid with increased concentration and the supplementary raw material liquid, and crystals are precipitated in the crystallization channel.

[0092] In one embodiment of the present application, the raw material liquid enters the raw material liquid sleeve 4 from the raw material liquid feed pipe 3, and the anti-solvent enters the channel of the raw material liquid sleeve 4 from the flow channel of the tapered tube 1 to mix with the raw material liquid to complete the precipitation process; after the mixed fluid enters the channel of the first anti-solvent sleeve 7, it mixes with the anti-solvent entering from the first dispersion hole 16 to further increase the solute supersaturation, so that the solvent inside the crystals obtained by precipitation is further precipitated; the mixed fluid enters the second anti-solvent sleeve 11 along the axial direction, mixes with the anti-solvent entering from the second dispersion hole 17, and further increases the solute supersaturation, so that the solvent wrapped in the crystals is completely precipitated.

[0093] In order to simplify the structure, the suction effect of the Venturi structure is utilized to provide a buffering effect through the first buffer chamber to ensure stable feeding. Optionally, the buffer chamber includes a first buffer chamber arranged in the first shell 14, the raw material liquid sleeve 4 is at least partially arranged in the first buffer chamber, at least one feed hole 2 is arranged on the raw material liquid sleeve 4, an annular gap is arranged between the raw material liquid sleeve 4 and the tapered tube 1, and the raw material liquid feed pipe 3 is arranged on the first shell 14; step (1) also includes: the raw material liquid passes through the raw material liquid feed pipe 3, the first buffer chamber, the feed hole 2 and the annular gap in sequence into the crystallization channel.

[0094] In order to simplify the structure, the suction effect of the Venturi structure is utilized to provide a buffering effect through the second buffer chamber to ensure stable feeding. Optionally, the buffer chamber includes a second buffer chamber arranged in the second shell 5, the first anti-solvent sleeve 7 is at least partially arranged in the second buffer chamber, the first anti-solvent sleeve 7 is provided with at least one first dispersion hole 16, and the first anti-solvent feed pipe 6 is arranged on the second shell 5; step (2) also includes: the anti-solvent passes through the first anti-solvent feed pipe 6, the second buffer chamber and the first dispersion hole 16 in sequence into the crystallization channel.

[0095] In order to simplify the structure, the suction effect of the Venturi structure is utilized to provide a buffering effect through the third buffer chamber to ensure stable feeding. Optionally, the buffer chamber includes a third buffer chamber arranged in the third shell 9, the first anti-solvent sleeve 7 is at least partially arranged in the third buffer chamber, the first anti-solvent sleeve 7 is provided with at least one second dispersion hole 17, and the supplementary raw material feed pipe 8 is arranged on the third shell 9; step (2) also includes: the supplementary raw material liquid enters the crystallization channel through the supplementary raw material feed pipe 8, the third buffer chamber and the second dispersion hole 17 in sequence.

[0096] In order to simplify the structure, the suction effect of the Venturi structure is utilized to provide a buffering effect through the fourth buffer chamber to ensure stable feeding. Optionally, the buffer chamber includes a fourth buffer chamber arranged in the third shell 9, the second anti-solvent sleeve 11 is at least partially arranged in the fourth buffer chamber, the second anti-solvent sleeve 11 is provided with at least one third dispersion hole 18, and the second anti-solvent sleeve 11 is arranged on the third shell 9; step (2) also includes: the anti-solvent enters the crystallization channel through the second anti-solvent sleeve 11, the fourth buffer chamber and the third dispersion hole 18 in sequence.

[0097] To obtain crystals of different shapes and particle sizes, optionally, step (2) also includes: changing the crystal shape and particle size by adjusting the relative feed rates of the raw material liquid and the anti-solvent; relatively increasing the anti-solvent feed rate helps to form fibrous precipitated crystals; relatively increasing the raw material liquid feed rate helps to form spherical precipitated crystals.

[0098] And / or the crystal shape and particle size are changed by adjusting the feed flow pattern of the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11. The first anti-solvent sleeve 7 can provide two feeding modes: radial feeding and tangential feeding, and the second anti-solvent sleeve 11 can provide tangential feeding. Feeding the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11 with the first dispersion hole 16 as the radial feeding direction is helpful to form fibrous precipitated crystals; feeding the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11 with the second dispersion hole 17 as the tangential feeding direction is helpful to form spherical precipitated crystals.

[0099] To obtain fibrous precipitated crystals, optionally, step (2) also includes: increasing the feed rate of at least one of the tapered tube 1, the first anti-solvent feed tube 6, and the second anti-solvent sleeve 11, and / or reducing the feed rate of the raw material liquid feed tube 3; and using the first dispersion hole 16 as the radial feeding direction of the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11 to feed, so as to obtain fibrous precipitated crystals.

[0100] In one embodiment of the present application, without changing the feed rate of the raw liquid feed pipe 3, the feed rates of the convergent tube 1, the first anti-solvent feed pipe 6, and the second anti-solvent sleeve 11 are increased, the first dispersion hole 16 is used as the radial feeding direction to feed the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11, and the raw liquid feed pipe 3 provides the raw liquid to obtain fibrous precipitated crystals.

[0101] To obtain spherical precipitated crystals, optionally, step (2) also includes: reducing the feed rate of at least one of the tapered tube 1, the first anti-solvent feed tube 6, and the second anti-solvent sleeve 11, and / or increasing the feed rate of the raw material liquid feed tube 3; and using the second dispersion hole 17 to feed the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11 in the tangential feeding direction, and the supplementary raw material feed tube 8 to provide supplementary raw material liquid to obtain spherical precipitated crystals.

[0102] In one embodiment of the present application, without changing the feed rate of the raw liquid feed pipe 3, while reducing the feed rates of the convergent tube 1, the first anti-solvent feed pipe 6, and the second anti-solvent sleeve 11, the first anti-solvent sleeve 7 and the second anti-solvent sleeve 11 are fed with the second dispersion hole 17 as the tangential feeding direction, the raw liquid feed pipe 3 provides the raw liquid, and the supplementary raw material feed pipe 8 provides the supplementary raw material liquid to obtain spherical precipitated crystals.

[0103] From the above description and practice, it can be seen that the anti-solvent crystallizer and crystallization method provided by the present application have the following advantages compared with the prior art: using the above-mentioned anti-solvent crystallizer, the buffer chamber provides a buffering effect for the raw material liquid and the anti-solvent entering the crystallization channel; the anti-solvent enters the crystallization channel from the tapered section and the first anti-solvent section respectively, and by setting up multiple entries into the anti-solvent, a controllable solute supersaturation gradient can be formed in the crystallization channel; the annular gap is conducive to the anti-solvent fluid shearing off the raw material liquid, so that the raw material liquid entering the clean channel is in a dispersed phase, the raw material liquid and the anti-solvent can be fully mixed in a short time, and the mixing between the fluids in the channel is strengthened, thereby obtaining a product with controllable crystal particle size and shape.

[0104] A person skilled in the art should understand that the above description is only a specific embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the scope of the present application should be included in the protection scope of the present application.

Claims

1. An anti-solvent crystallizer, characterized in that: include: A crystallizer body, the crystallizer body comprising a tapered section, a raw material liquid section, a first anti-solvent section and a gradually expanding section which are connected in sequence, the flow channels of the tapered section, the raw material liquid section, the first anti-solvent section and the gradually expanding section forming a crystallization channel; an annular gap is provided between the tapered section and the raw material liquid section, the raw material liquid section and the first anti-solvent section both have a buffer cavity between them and the inner wall of the crystallizer body, a raw material liquid feed pipe and a first anti-solvent feed pipe are arranged at intervals on the crystallizer body, the raw material liquid feed pipe and the first anti-solvent feed pipe are connected to the raw material liquid section and the first anti-solvent section respectively through the buffer cavity.

2. The anti-solvent crystallizer according to claim 1, characterized in that: The crystallizer body also includes at least one second anti-solvent section, which is connected between the first anti-solvent section and the gradually expanding section; the flow channel of the second anti-solvent section is connected to the crystallization channel, and the buffer cavity is provided between the second anti-solvent section and the inner wall of the crystallizer body; at least one second anti-solvent feed pipe is provided on the crystallizer body, and the second anti-solvent feed pipe is connected to the second anti-solvent section through the buffer cavity.

3. The anti-solvent crystallizer according to claim 2, characterized in that: At least one supplementary raw material liquid feed pipe is arranged on the crystallizer body, and the supplementary raw material liquid feed pipe is connected with the crystallization channel through the first anti-solvent section or the second anti-solvent section.

4. The anti-solvent crystallizer according to claim 3, characterized in that: The crystallizer body comprises a convergent pipe, a first shell, a second shell, a third shell and a divergent pipe connected in sequence, wherein a raw material liquid sleeve, a first anti-solvent sleeve and a second anti-solvent sleeve are arranged in the first shell, the second shell and the third shell in sequence; The convergent tube and the divergent tube form the convergent section and the divergent section respectively; the first shell and the raw material liquid sleeve form the raw material liquid section; the second shell and the first anti-solvent feed pipe form the first anti-solvent section; the third shell and the second anti-solvent feed pipe form the second anti-solvent section; The raw material liquid feed pipe, the first anti-solvent feed pipe, the supplementary raw material liquid feed pipe and the second anti-solvent feed pipe are respectively arranged on at least one of the first shell, the second shell and the third shell.

5. The anti-solvent crystallizer according to claim 4, characterized in that: The buffer chamber includes a first buffer chamber arranged in a first shell, the raw material liquid sleeve is at least partially arranged in the first buffer chamber, at least one feed hole is arranged on the raw material liquid sleeve, an annular gap is arranged between the raw material liquid sleeve and the tapered tube, the raw material liquid feed pipe is arranged on the first shell, and the raw material liquid feed pipe is connected with the crystallization channel through the first buffer chamber, the feed hole and the annular gap.

6. The anti-solvent crystallizer according to claim 5, characterized in that: The inlet end of the raw liquid sleeve includes a connecting pipe section and an inlet pipe section which are connected in sequence, the connecting pipe section is sleeved outside the reducer, an annular gap is formed between the connecting pipe section and the reducer, and the feed hole is arranged on the connecting pipe section; the inner diameter of the inlet pipe section is smaller than the inner diameter of the reducer.

7. The anti-solvent crystallizer according to claim 5 or 6, characterized in that: A plurality of protrusions spaced apart along the axial direction are arranged in the raw material liquid sleeve, and the protrusions are used to reduce the passing area of ​​the raw material liquid sleeve.

8. The anti-solvent crystallizer according to claim 7, characterized in that: The buffer chamber includes a second buffer chamber arranged in a second shell, the first anti-solvent sleeve is at least partially arranged in the second buffer chamber, the first anti-solvent sleeve is provided with at least one first dispersion hole, the first anti-solvent feed pipe is arranged on the second shell, and the first anti-solvent feed pipe is connected to the crystallization channel through the second buffer chamber and the first dispersion hole.

9. The anti-solvent crystallizer according to claim 8, characterized in that: The buffer chamber includes a third buffer chamber arranged in a third shell body, the first anti-solvent sleeve is at least partially arranged in the third buffer chamber, the first anti-solvent sleeve is provided with at least one second dispersion hole, the supplementary raw material liquid feed pipe is arranged on the third shell body, and the supplementary raw material liquid feed pipe is connected to the crystallization channel through the third buffer chamber and the second dispersion hole.

10. The anti-solvent crystallizer according to claim 9, characterized in that: The buffer chamber includes a fourth buffer chamber arranged in a third shell, the second anti-solvent sleeve is at least partially arranged in the fourth buffer chamber, the second anti-solvent sleeve is provided with at least one third dispersion hole, the second anti-solvent sleeve is arranged on the third shell, and the second anti-solvent sleeve is connected to the crystallization channel through the fourth buffer chamber and the third dispersion hole.

11. The anti-solvent crystallizer according to claim 10, characterized in that: At least one guide plate is arranged in the second anti-solvent sleeve.

12. A crystallization method using the anti-solvent crystallizer according to any one of claims 1 to 11, characterized in that: include: (1) The raw material liquid enters the raw material liquid section from the raw material liquid feed pipe through the buffer chamber, the anti-solvent enters the raw material liquid section from the tapered section through the annular gap and mixes with the raw material liquid, and crystals are precipitated in the crystallization channel to form a mixed fluid; (2) The mixed fluid enters the first anti-solvent section, the anti-solvent enters the first anti-solvent section from the first anti-solvent feed pipe through the buffer chamber to mix with the mixed fluid, crystals precipitate in the crystallization channel, and are discharged from the gradually expanding section.

13. The crystallization method of the anti-solvent crystallizer according to claim 12, characterized in that: The crystallizer body also includes at least one second anti-solvent section, and at least one second anti-solvent feed pipe is provided on the crystallizer body. Step (2) also includes: the mixed fluid of the first anti-solvent section enters the second anti-solvent section, the anti-solvent enters the second anti-solvent section from the second anti-solvent feed pipe through the buffer chamber to mix with the mixed fluid, and crystals are precipitated in the crystallization channel.

14. The crystallization method of the anti-solvent crystallizer according to claim 13, characterized in that: At least one feed pipe for supplementing raw material liquid is provided on the crystallizer body, and step (2) further comprises: the feed pipe for supplementing raw material liquid supplements raw material liquid to the crystallization channel through the first anti-solvent section or the second anti-solvent section.

15. The crystallization method of the anti-solvent crystallizer according to claim 14, characterized in that: The crystallizer body comprises a convergent pipe, a first shell, a second shell, a third shell and a divergent pipe connected in sequence; a raw material liquid sleeve, a first anti-solvent sleeve and a second anti-solvent sleeve are arranged in sequence in the first shell, the second shell and the third shell; Step (1) comprises: the raw material liquid enters the raw material liquid casing from the raw material liquid feed pipe, and the anti-solvent enters the raw material liquid casing from the reducer pipe to mix with the raw material liquid; Step (2) includes: the mixed fluid enters the first anti-solvent sleeve, the anti-solvent enters the first anti-solvent sleeve from the first anti-solvent feed pipe and mixes with the mixed fluid, crystals are precipitated in the crystallization channel, and a mixed fluid with increased concentration is formed; the supplementary raw material liquid feed pipe supplements the raw material liquid to the crystallization channel through the first anti-solvent sleeve or the second anti-solvent sleeve; the mixed fluid with increased concentration and the supplementary raw material liquid enter the second anti-solvent sleeve, the anti-solvent enters the second anti-solvent sleeve from the second anti-solvent feed pipe and mixes with the mixed fluid with increased concentration and the supplementary raw material liquid, and crystals are precipitated in the crystallization channel.

16. The crystallization method of the anti-solvent crystallizer according to claim 15, characterized in that: The buffer chamber includes a first buffer chamber arranged in a first shell, the raw material liquid sleeve is at least partially arranged in the first buffer chamber, at least one feed hole is arranged on the raw material liquid sleeve, an annular gap is arranged between the raw material liquid sleeve and the tapered tube, and the raw material liquid feed pipe is arranged on the first shell; step (1) also includes: the raw material liquid passes through the raw material liquid feed pipe, the first buffer chamber, the feed hole and the annular gap in sequence into the crystallization channel.

17. The crystallization method of the anti-solvent crystallizer according to claim 16, characterized in that: The buffer chamber includes a second buffer chamber arranged in a second shell, the first anti-solvent sleeve is at least partially arranged in the second buffer chamber, the first anti-solvent sleeve is provided with at least one first dispersion hole, and the first anti-solvent feed pipe is arranged on the second shell; step (2) also includes: the anti-solvent passes through the first anti-solvent feed pipe, the second buffer chamber and the first dispersion hole in sequence into the crystallization channel.

18. The crystallization method of the anti-solvent crystallizer according to claim 17, characterized in that: The buffer chamber includes a third buffer chamber arranged in a third shell, the first anti-solvent sleeve is at least partially arranged in the third buffer chamber, the first anti-solvent sleeve is provided with at least one second dispersion hole, and the supplementary raw material liquid feed pipe is arranged on the third shell; step (2) also includes: the supplementary raw material liquid passes through the supplementary raw material liquid feed pipe, the third buffer chamber and the second dispersion hole in sequence into the crystallization channel.

19. The crystallization method of the anti-solvent crystallizer according to claim 18, characterized in that: The buffer chamber includes a fourth buffer chamber arranged in a third shell, the second anti-solvent sleeve is at least partially arranged in the fourth buffer chamber, the second anti-solvent sleeve is provided with at least one third dispersion hole, and the second anti-solvent sleeve is arranged on the third shell; step (2) also includes: the anti-solvent enters the crystallization channel through the second anti-solvent sleeve, the fourth buffer chamber and the third dispersion hole in sequence.

20. The crystallization method of the anti-solvent crystallizer according to claim 19, characterized in that: Step (2) also includes: changing the crystal shape and particle size by adjusting the relative feed rate of the raw material liquid and the anti-solvent; and / or changing the crystal shape and particle size by adjusting the feed flow pattern of the first anti-solvent sleeve and the second anti-solvent sleeve.

21. The crystallization method of the anti-solvent crystallizer according to claim 20, characterized in that: Step (2) also includes: increasing the feed rate of at least one of the tapered tube, the first anti-solvent feed tube, and the second anti-solvent sleeve, and / or reducing the feed rate of the raw material liquid feed tube; and using the first dispersion hole as the radial feed direction of the first anti-solvent sleeve and the second anti-solvent sleeve to feed to obtain fibrous precipitated crystals.

22. The crystallization method of claim 21, wherein: Step (2) also includes: reducing the feed rate of at least one of the tapered tube, the first anti-solvent feed tube, and the second anti-solvent sleeve, and / or increasing the feed rate of the raw material liquid feed tube; and using the first anti-solvent sleeve and the second anti-solvent sleeve to feed with the second dispersion hole as the tangential feed direction, and the supplementary raw material liquid feed pipe to provide supplementary raw material liquid to obtain spherical precipitated crystals.

Images