Crystallization device

Abstract

The utility model provides a crystallization device which is particularly provided with a double-layer inner cylinder and an outer cylinder, so that the diameter of a crystal grain growth region at the lower section of the inner cylinder is reduced, and the descending speed of a solution in the crystal grain growth region is accelerated, thereby accelerating the renewal of the crystal surface, reducing the adhesion of organic components and preventing the interference of the organic components on the normal growth of the crystal; meanwhile, the diameter of a clarification area at the upper part of the outer cylinder is enlarged, the rising speed of the solution in the area is reduced, the disturbance suffered by the solution is reduced, the floating and separation of organic components in the solution are facilitated, and the quality and purity of the final crystal are further guaranteed; in addition, the crystallization device is compatible with two crystallization processes of evaporative crystallization and cooling crystallization, more excellent operation experience and process selection are provided for users due to the flexibility of the crystallization device, and diversified production requirements are ensured to be effectively met.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of concentration crystallization separation, further relates to a crystallization device. BACKGROUND

[0002] The existing concentration crystallization separation technology is divided into two kinds, one is evaporation crystallization, that is, by evaporating the solvent, the solute reaches the supersaturated state, thereby precipitating the crystal. The other is freeze crystallization, which takes advantage of the feature that the solubility of the solute in the solvent decreases with the decrease of temperature, and the solute is precipitated by reducing the temperature. These two technologies usually require different crystallizer structures to achieve.

[0003] Concentration crystallization technology is commonly used for the separation and purification of inorganic salts and the separation and purification of high-boiling organic matter. However, it has always been a technical problem in the concentration crystallization industry to concentrate and crystallize inorganic salts from high-concentration salt water containing organic matter, because the presence of a small amount or even trace amount of complex organic components in the solution can change its surface tension and hinder the growth of crystal grains, and in severe cases, even cannot form crystal grains.

[0004] Therefore, there is an urgent need for a crystallization device that can be applied to both evaporation crystallization and freeze crystallization, and can effectively separate organic matter and has high crystallization efficiency. SUMMARY

[0005] In view of the problems of existing crystallization devices, such as organic matter pollution hindering crystal growth and the crystallization device only being able to perform a single crystallization method, the utility model aims to provide a crystallization device, which is particularly designed with a double-layer structure of an inner cylinder and an outer cylinder to optimize the crystallization process, reduce the diameter of the lower section of the inner cylinder, and adopt a high-flow design. Such configuration can quickly refresh the crystal surface, effectively reduce the adhesion of organic components, thereby avoiding the interference of organic components with crystal growth and improving the purity of the crystal. At the same time, the diameter of the upper section of the outer cylinder is expanded, and a low-flow and low-disturbance scheme is implemented, which helps the floating and separation of organic components.

[0006] In order to achieve the above-mentioned purpose, the utility model provides the following technical scheme:

[0007] A crystallization device, comprising: an outer cylinder and an inner cylinder arranged inside the outer cylinder, the outer wall of the inner cylinder and the outer cylinder have a gap for liquid flow, and the opening at the bottom of the inner cylinder is communicated with the gap.

[0008] The inner cylinder top is provided with a liquid inlet, and the inner cylinder interior is divided into a supersaturation crystallization zone and a crystal grain growth zone from top to bottom, the diameter of the supersaturation crystallization zone is greater than that of the crystal grain growth zone, so that the descending flow rate of the supersaturation crystallization zone is lower than that in the crystal grain growth zone; the gap is divided into a clarification zone and a crystal grain sedimentation zone from top to bottom, the clarification zone is provided with an organic component discharge port for outputting organic components, and the crystal grain sedimentation zone is provided with a suspension discharge port for outputting crystals reaching a target particle size; the diameter of the clarification zone is greater than that of the crystal grain sedimentation zone, so that the ascending flow rate in the clarification zone is lower than that in the crystal grain sedimentation zone.

[0009] In some embodiments, the descending flow rate of the supersaturation crystallization zone is less than 0.2-0.5 m / s, and the descending flow rate in the crystal grain growth zone is 0.6-1.2 m / s; the ascending flow rate in the crystal grain sedimentation zone is 0.3-0.6 m / s, and the ascending flow rate in the clarification zone is 0.1-0.3 m / s.

[0010] In some embodiments, the outer cylinder and the inner cylinder are coaxially arranged, both adopt a cylinder structure with a wide upper part and a narrow lower part, and are divided into an upper section cylinder and a lower section cylinder, the diameter of the upper section cylinder is 2-3 times that of the lower section cylinder, and the height of the upper section cylinder is 1-1.5 times that of the lower section cylinder.

[0011] In some embodiments, the top of the clarification zone is provided with a clarification tank, the tank top of the clarification tank is communicated with the organic component discharge port, and the tank bottom of the clarification tank is provided with a clear liquid discharge port; the height of the clarification tank is 500-1000 mm, and the vertical distance between the tank top of the clarification tank and the top of the outer cylinder is 800-1200 mm.

[0012] In some embodiments, a circulating liquid pipeline is further included, which is communicated with the liquid inlet and the clarification zone respectively; a heat exchanger is arranged on the circulating liquid pipeline, for adjusting the temperature of the liquid in the circulating liquid pipeline; a circulating pump is arranged on the circulating liquid pipeline, for providing conveying power for the liquid in the circulating liquid pipeline.

[0013] In some embodiments, the crystallization device further includes a circulating liquid discharge port, which is arranged at the upper part of the outer cylinder in the vertical direction, one end of the circulating liquid pipeline is connected with the circulating liquid discharge port, and the other end is communicated with the liquid inlet.

[0014] In some embodiments, a feed pipeline for conveying a solution to be treated is further included, which is communicated with the circulating liquid pipeline between the circulating liquid discharge port and the circulating pump.

[0015] In some embodiments, the inner cylinder top is further provided with a vapor outlet for discharging the gas generated by evaporation crystallization.

[0016] In some embodiments, the crystallization device further comprises a controller and an interface meter and a density meter connected to the controller; the interface meter is used to measure the interface position between the organic component and the clear liquid in the clarifying tank; the controller is connected to the valve at the organic component outlet to control the opening and closing of the organic component outlet according to the reading of the interface meter; the controller is connected to the valve at the clear liquid outlet to control the opening and closing of the clear liquid outlet; the density meter is used to measure the crystal density at the suspension outlet; and the controller is connected to the valve at the suspension outlet to control the opening and closing of the suspension outlet according to the reading of the density meter.

[0017] In some embodiments, the crystallization device further comprises a liquid level meter connected to the controller, which is used to detect the liquid level in the outer cylinder, and the controller is used to control the amount of solution to be treated into the inner cylinder according to the reading of the liquid level meter.

[0018] Compared with the prior art, the crystallization device has the following beneficial effects:

[0019] 1. The crystallization device is carefully designed in the structure of the inner cylinder and the outer cylinder to optimize the crystallization process. In the lower section of the inner cylinder, that is, the crystal grain growth area, a high flow rate design is adopted. The purpose of this is to quickly refresh the crystal surface during the crystal growth process, effectively reduce the adhesion of organic matter, avoid affecting the crystal growth, and improve the purity of the crystal. At the same time, in the upper section of the outer cylinder, that is, the clarification area, a low flow rate and low disturbance layout is adopted. This design helps the floating and separation of the organic component, and further ensures the quality and purity of the final product.

[0020] 2. The crystallization device provided by the utility model is provided with a circulating liquid pipeline, which circulates and utilizes the solution in the clarification area, and re-introduces the solution into the inner cylinder for the crystallization process, so that the solute in the solution can rely on the existing small crystal grains in the circulating liquid as effective crystal nuclei to quickly coagulate to form larger crystals, thereby promoting the increase of the crystal grain size, effectively reducing the occurrence of secondary nucleation, and improving the crystallization efficiency and the uniformity of the crystal.

[0021] 3. Unlike the traditional crystallizer on the market which can only perform single evaporation crystallization or cooling crystallization, the crystallization device provided by the utility model is provided with a heat exchanger and realizes the compatibility of the two different crystallization methods through the unique structure design of the inner cylinder and the outer cylinder. This design greatly improves the flexibility and efficiency of the crystallization process, provides a more extensive application range and a more efficient crystallization solution for users.

[0022] 4. The crystallization device provided by the utility model adopts a highly automated control system, an interface meter and an organic component discharge control loop are arranged, the controller can intelligently adjust the discharge of the organic component according to the real-time reading of the interface meter, in addition, a clear liquid discharge control loop, a suspension liquid discharge control loop and a solution feeding control loop are arranged, the automatic discharge of the clear liquid and the suspension liquid containing the target particle size crystal grains and the automatic replenishment of the crystallization solution are realized, the device has high automation degree in operation and is simple to operate, not only the continuity and stability of the crystallization process are ensured, but also the crystallization efficiency is remarkably improved, great convenience and efficiency improvement are brought to production operation. BRIEF DESCRIPTION OF DRAWINGS

[0023] The above-mentioned features, technical characteristics, advantages and implementation manners of the utility model will be further described in the following in a clear and understandable manner in combination with the preferred embodiments and the drawings.

[0024] Figure 1 The structure diagram of the crystallization device provided by the utility model is shown.

[0025] Explanation of reference numerals:

[0026] 1 - outer cylinder; 2 - inner cylinder; 3 - liquid inlet; 4 - suspension liquid discharge port; 5 - steam outlet; 6 - circulating liquid discharge port; 7 - clarifying tank; 8 - circulating liquid pipeline; 9 - heat exchanger; 10 - circulating pump; 11 - feeding pipeline; 12 - controller; 13 - interface meter; 14 - liquid level meter; 15 - organic component discharge control loop; 16 - suspension liquid discharge control loop; 17 - solution feeding control loop. DETAILED DESCRIPTION

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, the specific implementation manners of the utility model will be described below with reference to the drawings. Obviously, the drawings described below are only some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained according to these drawings without creative labor, and other implementation manners can also be obtained.

[0028] In order to make the drawing simple, only the parts related to the utility model are shown in each drawing, and they do not represent the actual structure of the product. In addition, in order to make the drawing simple and easy to understand, in some drawings, only one of the parts with the same structure or function is shown, or only one of them is marked. In this paper, "one" not only means "only one", but also means "more than one".

[0029] It should be further understood that the term "and / or" used in the description of the utility model and the appended claims should mean any combination of one or more of the associated listed terms and all possible combinations, and includes these combinations.

[0030] In this article, it should be noted that unless otherwise specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected, it can be mechanical connection, or electrical connection, it can be directly connected, or indirectly connected through intermediate medium, it can be the communication inside two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0031] In addition, in the description of the utility model, the terms "first", "second" and the like are only used for distinguishing description, and cannot be understood as indicating or implying relative importance.

[0032] The utility model provides a kind of crystallization device, as shown in Figure 1 The outer wall between the inner cylinder 2 and the outer cylinder 1 has a gap for the flow of liquid, and the bottom of the inner cylinder 2 is open, which communicates with the gap, and the liquid in the inner cylinder 2 flows into the gap through the opening.

[0033] The top of the inner cylinder 2 is provided with a liquid inlet 3, and the inside of the inner cylinder 2 is divided into a supersaturated crystallization zone and a crystal grain growth zone from top to bottom. The solution to be crystallized enters the inner cylinder through the liquid inlet 3, and evaporates and crystallizes (or cools and crystallizes) in the supersaturated crystallization zone. The solution is supersaturated and precipitates solute. Most of the solute will form crystal grains around the crystal nucleus in the circulating liquid, and a small amount will form crystal nucleus. As the solution flows to the crystal grain growth zone, the crystal nucleus grows into crystal grains.

[0034] Further, the diameter of the supersaturated crystallization zone is greater than the diameter of the crystal grain growth zone, so that the descending flow rate of the liquid in the supersaturated crystallization zone is lower than the descending flow rate of the liquid in the crystal grain growth zone, that is, a high flow rate is designed in the crystal grain growth zone. In this way, the crystal can be quickly refreshed on the surface during the growth process, and the adhesion of organic matter can be reduced.

[0035] Preferably, the diameter of the supersaturated crystallization zone is configured to satisfy that the descending flow rate of the liquid in this area is less than 0.2-0.5 m / s, and the diameter of the crystal grain growth zone is configured to satisfy that the descending flow rate of the liquid in this area is 0.6-1.2 m / s.

[0036] The gap is divided into a clarification zone and a crystal grain settling zone from top to bottom. The clarification zone is provided with an organic component discharge port for outputting organic components. The crystal grain settling zone is provided with a suspension discharge port 4 for outputting crystals reaching a target particle size. The diameter of the clarification zone is greater than the diameter of the crystal grain settling zone. Such a design makes the upward flow rate in the clarification zone lower than the upward flow rate in the crystal grain settling zone.

[0037] The crystal grains in the crystal grain growth zone flow into the crystal grain settling zone with the solution from the opening first, and gradually grow in size while the solution rises, with the rising speed slowing down. The target particle size is reached at the suspension discharge port 4, which is also the region with the highest concentration of crystal grains in the solution. As the solution continues to rise to the top of the clarification zone, the concentration of microcrystals in the solution is lower, and the particle size is smaller. The solution is clear. If the solution contains organic components, the organic components will float on the surface of the liquid under the action of the density difference and be discharged through the organic component discharge port.

[0038] Preferably, the suspension discharge port 4 can be provided with three ports. In different working conditions, the crystal density readings of different discharge ports are selected.

[0039] Preferably, the diameter of the crystal grain settling zone is configured to satisfy the upward flow rate of the liquid in the region at 0.3-0.6 m / s, and the diameter of the clarification zone is configured to satisfy the upward flow rate of the liquid in the region at 0.1-0.3 m / s.

[0040] In some embodiments, the outer cylinder 1 and the inner cylinder 2 are coaxially arranged, and both adopt a cylindrical structure with a wide upper part and a narrow lower part. The outer cylinder 1 and the inner cylinder 2 each include an upper section cylinder and a lower section cylinder. The diameter of the upper section cylinder is 2-3 times the diameter of the lower section cylinder, and the height (tangent height) of the upper section cylinder is 1-1.5 times the height (tangent height) of the lower section cylinder. Taking the inner cylinder 2 as an example, the diameter of the supersaturated crystallization zone is 2-3 times the diameter of the crystal grain growth zone, and the height of the supersaturated crystallization zone is 1-1.5 times the height of the crystal grain growth zone.

[0041] In some embodiments, the inner cylinder 2 is further provided with a steam outlet 5 at the top for discharging the gas generated by the evaporation crystallization.

[0042] In some embodiments, the top of the clarification zone is provided with a clarification tank 7. The tank top of the clarification tank 7 is in communication with the organic component discharge port. The tank bottom of the clarification tank 7 is provided with a clear liquid discharge port. After the solution flows into the clarification tank 7, the organic components float on the surface of the liquid due to the density difference. The organic components on the surface are discharged through the organic component discharge port, and the clear liquid without organic components in the lower part is discharged through the clear liquid discharge port.

[0043] Preferably, the height of the clarification tank is 500-1000 mm, and the vertical distance between the tank top of the clarification tank and the top of the outer cylinder is 800-1200 mm.

[0044] In some embodiments, the crystallization device further comprises a circulating liquid pipeline 9, which is connected to the liquid inlet 3 and the clarification zone respectively.

[0045] Further, the outer cylinder 1 is provided with a circulating liquid outlet 6, which is preferably arranged at the upper part of the outer cylinder 1 in the vertical direction, but the position of the circulating liquid outlet 6 is lower than the bottom of the clarification tank 7. One end of the circulating liquid pipeline 9 is connected to the circulating liquid outlet 6, and the other end is connected to the liquid inlet 3.

[0046] Further, the circulating liquid pipeline 9 is provided with a heat exchanger 9, which is used to adjust the temperature of the liquid in the circulating liquid pipeline 9. The heat exchanger 9 selects an evaporator or a cooler according to the crystallization method (evaporative crystallization / cooling crystallization).

[0047] Further, the circulating liquid pipeline is provided with a circulating pump 10, which is used to provide power for the liquid in the circulating liquid pipeline 9.

[0048] After the solution rises from the crystal grain settling zone to the clarification zone, the rising speed of the solution is further reduced due to the settling effect, and the finer crystals settle downward. When rising to the circulating liquid outlet 6 in the middle, only the tiny crystal grains with a particle size of less than 100 μm are left in the solution, and the crystal grain concentration is also reduced to 100 ppm-300 ppm. The solution enters the circulating liquid pipeline 9 through the circulating liquid outlet 6, is adjusted in temperature (heated or cooled) after being pressurized as a crystal nucleus, and then enters the inner cylinder 2 for crystallization.

[0049] In some embodiments, the crystallization device further comprises a feed pipeline 11 for feeding the solution to be treated. The feed pipeline 11 can be directly connected to the liquid inlet 3 to feed the heated (or cooled) solution to be treated into the inner cylinder 2. More preferably, the feed pipeline 11 is connected to the circulating liquid pipeline between the circulating liquid outlet 6 and the circulating pump 10, so that the solution to be treated is pressurized and temperature-adjusted together with the solution in the circulating liquid pipeline, and then fed into the inner cylinder 2 for crystallization.

[0050] In some embodiments, the crystallization device further comprises a controller 12 and an interface meter 13, a density meter, an organic component outlet control loop 15, a clear liquid outlet control loop, and a suspension liquid outlet control loop 16 connected to the controller 12.

[0051] The interface meter 13 is used to measure the interface position between the organic component and the clear liquid in the clarification tank 7. The organic component outlet control loop 15 is connected to the valve on the pipeline at the organic component outlet, so as to control the opening and closing of the organic component outlet according to the reading of the interface meter 12, thereby controlling the discharge of the organic component.

[0052] The clear liquid outlet control loop is connected to the valve on the pipeline at the clear liquid outlet, so as to control the opening and closing of the clear liquid outlet, thereby controlling the discharge of the clear liquid.

[0053] The density meter is used to measure the crystal density at the suspension outlet 4. The suspension discharge control circuit 16 is connected to the valve control on the pipeline at the suspension discharge port to control the opening and closing of the suspension discharge port according to the reading of the density meter, thereby controlling the discharge of the suspension.

[0054] Furthermore, the crystallization device also includes: a liquid level meter 14 and a solution feed control circuit 17 respectively connected to the controller 12, the liquid level meter 14 is used to detect the liquid level in the outer cylinder 1, and the solution feed control circuit is used to control the delivery of the solution to be treated into the inner cylinder 2 according to the reading of the liquid level meter 14 to maintain the liquid level of the outer cylinder 2 stable, that is, to control the amount of the solution to be treated delivered by the feed pipeline 11 to the inner cylinder 2.

[0055] The operation process of the crystallization device is as follows:

[0056] The solution to be evaporated and crystallized (frozen crystallized) is metered and fed in a solution feed control circuit 11. The metered solution is mixed with the circulating liquid in the circulating liquid pipeline 9 through the feed pipeline 11 and enters the circulating pump 10 for pressurization and the heat exchanger 9 for heating (or cooling). Then, the solution enters the supersaturated crystallization zone of the inner cylinder 2 through the liquid inlet 3, flash vaporizes, and the gas is discharged from the steam outlet 5. The solution is supersaturated and solutes are precipitated. Most of the solutes will form grains with the crystal nuclei in the circulating liquid as the center, and a small amount of solutes will form new crystal nuclei. As the solution flows from top to bottom in the inner cylinder 2, the crystal nuclei gradually grow into grains and flow into the grain sedimentation zone through the bottom opening of the inner cylinder 2.

[0057] The grains continue to grow as the solution rises in the grain sedimentation zone, and the rising speed gradually slows down, and reaches the target particle size near the suspension discharge port 4, and the rising speed becomes zero. This is also the area with the maximum crystal concentration. The density of the crystal in the suspension is measured and controlled by the density meter, and the valve on the pipeline at the suspension discharge port 4 is controlled by the suspension discharge control circuit 16 to control the discharge flow rate.

[0058] As the solution continues to rise into the clarification zone, the crystal concentration in the solution decreases rapidly due to sedimentation, the rising flow rate further decreases, and smaller crystals begin to settle downward. When the solution rises to the circulating liquid discharge port 6 in the middle of the outer tube 1, only tiny crystals with a particle size of less than 100μm remain in the solution, and the crystal concentration is also reduced to 100ppm~300PPm. These crystals serve as crystal nuclei and enter the circulating liquid pipeline 6 through the circulating liquid discharge port 6. After being pressurized and heated, they enter the supersaturated crystallization zone in the upper section of the inner tube 2 from the liquid inlet 3 as circulating liquid, and flash evaporation occurs. The flash gas is discharged through the steam outlet 5, and the solution changes from a saturated state to a supersaturated state, and the solute crystals precipitate.

[0059] The concentration of microcrystals in the solution above the circulating liquid discharge port 6 is lower, the particle size is smaller, and the solution is in a clear state. Due to the density difference, the organic components in the solution float on the liquid surface and preferentially enter the clarification tank 7. Based on the reading of the interface meter 13, the controller 12 controls the valves on the pipeline at the organic component discharge port and the valves on the pipeline at the clear liquid discharge port through the organic component discharge control circuit 15 and the clear liquid discharge control circuit, respectively, to control the automatic discharge of the organic components and the clear liquid.

[0060] The raw material supply of the crystallization device is automatically replenished by the solution feed control circuit 17 based on the reading of the liquid level meter 14 to maintain the liquid level in the outer cylinder 1 in a stable state.

[0061] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A crystallization device, characterized in that: include: An outer cylinder and an inner cylinder arranged inside the outer cylinder, a gap for liquid flow is defined between the outer wall of the inner cylinder and the outer cylinder, and an opening at the bottom of the inner cylinder is connected to the gap; The top of the inner cylinder is provided with a liquid inlet, and the interior of the inner cylinder is divided into a supersaturated crystallization zone and a grain growth zone from top to bottom. The diameter of the supersaturated crystallization zone is larger than the diameter of the grain growth zone, so that the descending flow rate in the supersaturated crystallization zone is lower than the descending flow rate in the grain growth zone; The gap is divided into a clarification zone and a crystal grain settling zone from top to bottom. The clarification zone is provided with an organic component discharge port for discharging organic components, and the crystal grain settling zone is provided with a suspension discharge port for discharging crystals reaching a target particle size. The diameter of the clarification zone is greater than the diameter of the crystal grain settling zone, so that the rising flow velocity in the clarification zone is lower than the rising flow velocity in the crystal grain settling zone.

2. The crystallization device according to claim 1, characterized in that The descending velocity in the supersaturated crystallization zone is less than 0.2 to 0.5 m / s, and the descending velocity in the grain growth zone is 0.6 to 1.2 m / s; The rising flow velocity in the crystal grain settling zone is 0.3 to 0.6 m / s, and the rising flow velocity in the clarification zone is 0.1 to 0.3 m / s.

3. The crystallization device according to claim 1, characterized in that The outer cylinder is coaxially arranged with the inner cylinder, and both adopt a cylindrical structure that is wide at the top and narrow at the bottom, and are divided into an upper cylinder and a lower cylinder. The diameter of the upper cylinder is 2 to 3 times the diameter of the lower cylinder, and the height of the upper cylinder is 1 to 1.5 times the height of the lower cylinder.

4. The crystallization device according to claim 1, characterized in that A clarification tank is provided on the top of the clarification zone, the top of the clarification tank is connected to the organic component discharge port, and a clear liquid discharge port is provided at the bottom of the clarification tank; The height of the clarification tank is 500-1000 mm, and the vertical distance between the top of the clarification tank and the top of the outer cylinder is 800-1200 mm.

5. The crystallization device according to claim 1, characterized in that It also includes a circulating liquid pipeline, which is connected to the liquid inlet and the clarification area respectively; The circulating liquid pipeline is provided with a heat exchanger for adjusting the temperature of the liquid in the circulating liquid pipeline; The circulating liquid pipeline is provided with a circulating pump for providing conveying power for the liquid in the circulating liquid pipeline.

6. The crystallization device according to claim 5, characterized in that Also includes: circulating liquid discharge port, The circulating liquid discharge port is arranged at the upper part of the outer cylinder in the vertical direction, one end of the circulating liquid pipeline is connected to the circulating liquid discharge port, and the other end is communicated with the liquid inlet.

7. The crystallization device according to claim 6, characterized in that It also includes a feed pipeline for conveying the solution to be treated, The feed pipeline is communicated with the circulating liquid pipeline between the circulating liquid outlet and the circulating pump.

8. The crystallization device according to claim 1, characterized in that The top of the inner cylinder is also provided with a steam outlet for discharging the gas generated by evaporation and crystallization.

9. The crystallization device according to claim 4, characterized in that Also includes a controller and an interface meter and a density meter connected to the controller; The interface meter is used to measure the boundary position between the organic components and the clear liquid in the clarification tank; The controller is connected to the valve at the organic component discharge port to control the opening and closing of the organic component discharge port according to the reading of the interface meter; The controller is connected to the valve at the clear liquid discharge port to control the opening and closing of the clear liquid discharge port; The density meter is used to measure the crystal density at the outlet of the suspension; The controller is connected to the valve at the suspension discharge port to control the opening and closing of the suspension discharge port according to the reading of the density meter.

10. The crystallization device according to claim 9, characterized in that It also includes: a liquid level meter connected to the controller, the liquid level meter is used to detect the liquid level in the outer cylinder, and the controller is used to control the amount of solution to be treated delivered to the inner cylinder according to the reading of the liquid level meter.

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