Plate type crystallizer and purification system

Abstract

The utility model relates to a plate-type crystallizer and a purification system.The plate-type crystallizer comprises a shell, a feeding port is formed in the upper portion of the shell, a discharging port is formed in the lower portion of the shell, the feeding port is communicated with a raw material liquid distributor, and the raw material liquid distributor comprises a material distribution pipe network; the material distribution pipe network comprises a feeding pipeline communicated with the feeding port, a distribution main pipe communicated with the feeding pipeline and a plurality of distribution branch pipes communicated with the distribution main pipe, a plurality of notches are formed in the bottoms of the distribution branch pipes, the notches are in the shape with the middle small and the two ends large, and a plurality of heat exchange components are arranged in the shell and arranged in parallel in the transverse direction. The heat exchange components are provided with first heat exchange medium inlets and first heat exchange medium outlets, the heat exchange components correspond to the notches in a one-to-one mode, and the first heat exchange medium inlets and the first heat exchange medium outlets communicate with a heat exchange medium feeding pipe and a heat exchange medium discharging pipe correspondingly.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chemical equipment, in particular to a plate type crystallizer and a purification system. BACKGROUND

[0002] In recent years, with the continuous development of new energy, chemical, food, pharmaceutical and other industries, the market has higher and higher requirements for the purity of chemical raw materials. Correspondingly, higher requirements are put forward for the purification limit, impurity removal rate, separation efficiency and environmental protection of the existing separation and purification method.

[0003] According to the different ways of saturation degree, the industrial crystallization process can be divided into evaporation crystallization, salting-out crystallization, cooling crystallization and reaction crystallization. Since evaporation crystallization consumes the most heat energy, the scaling problem of the heating surface will also make the operation difficult. Both salting-out crystallization and reaction crystallization need recovery equipment to handle the mother liquor and separate too many impurities. Therefore, cooling crystallization is generally used for purification in industry. Cooling crystallization, also known as melt crystallization, can be divided into suspension melt crystallization and layer melt crystallization.

[0004] Suspension melt crystallization utilizes the different solubility and different crystal forms of substances to create corresponding crystallization conditions, so that solid substances are precipitated from the raw material liquid in the form of high-purity solids, suspended in the liquid, and then the corresponding mother liquor is separated to ensure the purity of the crystals. The energy consumption is relatively small, and it is also easy to scale up and realize continuous production. Layer melt crystallization can be divided into static crystallization and dynamic falling film crystallization. The principle of both is to use a heat exchange component to cool the product in the raw material liquid and crystallize it on the heat exchange surface of the heat exchange component. Then the mother liquor is discharged, and the impurities wrapped in the crystallization process are removed by sweating to obtain the product raw material liquid, avoiding the possible breakage of the crystals caused by mechanical separation process and reducing the use of moving equipment. Layer melt crystallization has the advantages of simple process steps, high product purity and low energy consumption, and is widely used in the preparation of high-purity products.

[0005] Static crystallization includes three stages: temperature reduction crystallization, temperature rise sweating and temperature rise melting. In the temperature reduction crystallization process, the raw material liquid is first sent into the crystallizer, and the raw material liquid is cooled and crystallized by the heat exchange component. The generated crystals adhere to the surface of the heat exchange component. When the crystal layer reaches the appropriate thickness, the mother liquor is discharged. In the temperature rise sweating process, the heat exchange component is used to heat the crystal layer on the surface of the heat exchange component by heat conduction, melt part of the crystals and flow out while carrying out part of the impurities wrapped in them, so as to make the remaining crystal layer purer. In the temperature rise melting process, the remaining crystals are melted to obtain the corresponding product.

[0006] The static crystallizer can be divided into a plate type crystallizer and a column type crystallizer, and a plurality of cooling fins or tube bundles are contained in the static crystallizer respectively. A cooling medium circulates in the fins or tube bundles, and a raw material liquid is saturated at a high temperature and crystallized outside the fins or tube bundles. Since the thickness of a crystal layer gradually increases from the beginning of crystallization to the completion of crystallization, the efficiency of heat conduction is reduced, the heat exchange efficiency is low, the crystallization time is long, and the separation effect is reduced. At the same time, since the material does not flow, the crystallization process is uneven, impurities are more wrapped, and the purity, production capacity and yield of the product are affected.

[0007] CN217119379U discloses a static crystallization separation device, which comprises two or more crystallization separation modules, and each separation module comprises a shell, a material distribution pipe, a material distribution head, a heat exchange pipe medium distribution cross pipe (vertical pipe), a heat exchange component, a baffle, a crystallization fin and a material collection tank. The device can realize accurate distribution of the material on the crystallization fin range and crystallization of multiple materials. However, the heat transfer mode of the crystallizer in this scheme is only heat radiation in the early stage, the heat transfer effect is poor, and if the material continues to be fed for crystallization, the generated crystals are easy to block the outlet, the mother liquor cannot be completely discharged, the crystallization separation effect is poor, the efficiency is low, and the production capacity is low.

[0008] CN215137051U discloses a static crystallization separator, which comprises a box body, a plate pipe, a bottom cover, a raw material liquid inlet pipe, a refrigerant medium inlet and outlet pipe, a mounting plate, a sliding rod, a scraper and a transmission device, and the efficiency of heat conduction is improved. However, the crystal forms of different substances are different, the nucleation and crystal growth modes on the corrugated plate-shaped tube plate are different, and the mechanical separation using the scraper will cause the crystal to be broken and more impurities to be wrapped when growing again. Moreover, the crystals scraped off by the scraper are accumulated on the mesh plate, and the impurities wrapped in the crystals cannot be removed through the process of heating and sweating.

[0009] CN113877235A discloses a static crystallizer and a crystallization method, which comprises a shell and a cavity arranged in the shell. At least one heat exchange pipe is arranged in the cavity, and the heat exchange pipe is provided with a telescopic component. The telescopic direction of the telescopic component is not parallel to the axial direction of the heat exchange pipe. The structure of the crystallizer in this scheme can improve the heat exchange efficiency, but the non-flow of the material in the cavity can easily cause uneven crystallization process, more serious impurity wrapping, and affect the purity, production capacity and yield of the product. Practical new type

[0010] In view of the above prior art defects, the plate type crystallizer and purification system are provided to solve the above technical problems, such as low heat exchange efficiency, long crystallization time, reduced separation effect, non-uniform crystallization process, more serious impurity wrapping, and the like.

[0011] To achieve the above object, the scheme of the present application is as follows:

[0012] In a first aspect, the plate type crystallizer comprises a shell, an inlet is arranged at the upper portion of the shell, an outlet is arranged at the lower portion of the shell, a raw material liquid distributor is communicated with the inlet, the raw material liquid distributor comprises a material distribution pipe network, the material distribution pipe network comprises an inlet pipe communicated with the inlet, a distribution main pipe communicated with the inlet pipe, and a plurality of distribution branch pipes communicated with the distribution main pipe, a plurality of notches are arranged at the bottom of the distribution branch pipe, the notches are in a shape of small in the middle and large at both ends, a plurality of heat exchange components are arranged in the shell, all the heat exchange components are arranged in parallel along the transverse direction, the heat exchange components are provided with a first heat exchange medium inlet and a first heat exchange medium outlet, the heat exchange components are one-to-one corresponding to the notches, and the first heat exchange medium inlet and the first heat exchange medium outlet are respectively communicated with a heat exchange medium inlet pipe and a heat exchange medium outlet pipe.

[0013] The principle of the plate type crystallizer is that the notches are arranged at the bottom of the distribution branch pipe and are in a shape of small in the middle and large at both ends, so that the material is adjusted from a single strand to a uniform water curtain type multi-strand, flows through the surface of the heat exchange component, forms a uniform crystallization layer, and makes the crystal distribution more uniform, improves the heat exchange efficiency of the raw material liquid and the heat exchange medium in the processes of cooling crystallization and heating sweating, relatively reduces the impurity wrapping between the crystal layers during crystallization, effectively discharges the mixed part of the crystal containing the impurities during sweating, improves the effects of crystallization and sweating, and ensures the purification effect of the raw material liquid.

[0014] Optionally, the shell is provided with a jacket, and the jacket is provided with a heat exchange medium through hole.

[0015] Specifically, the shell is additionally provided with a jacket, and the jacket is provided with a heat exchange medium passage, heat exchange medium can be introduced into the jacket, when cooling crystallization and heating sweating, the raw material liquid on the inner wall of the plate crystallizer can be crystallized and sweated synchronously, the uniformity of the crystal layer is ensured, and the pollution of impurities on the wall of the traditional static crystallizer is reduced.

[0016] Optionally, the surface of the heat exchange component is provided with a concave-convex texture layer.

[0017] Specifically, the concave-convex texture layer is additionally arranged on the surface of the heat exchange component, the crystal layer is attached to the surface of the concave-convex texture layer, the adverse effects of the crystal layer falling off from the surface of the heat exchange component on purity and yield are prevented, and then the purity and yield are improved.

[0018] Optionally, a wire mesh layer is additionally arranged in the shell, the wire mesh layer is arranged on at least one side of the upper and lower sides of the heat exchange component, and is arranged in parallel with the heat exchange component.

[0019] Specifically, the wire mesh layer is additionally arranged in the shell, the wire mesh layer is arranged on at least one side of the upper and lower sides of the heat exchange component, and is arranged in parallel with the heat exchange component, the adverse effects of the crystal layer on purity and yield caused by the crystal layer in the heating and sweating process are prevented through the wire mesh layer, and then the purity and yield are improved.

[0020] Optionally, the distance between adjacent heat exchange components is 20-200mm.

[0021] Optionally, the distance between the wire mesh layer and the heat exchange component is 5-60mm.

[0022] Specifically, the distance between the wire mesh layer and the heat exchange component is 5-60mm, the function of preventing the crystal layer from being crystallized in the heating and sweating process is further played through the wire mesh layer, and then the purity and yield are further improved.

[0023] Optionally, a kettle body for storing materials is additionally arranged in the shell, and the kettle body is arranged between the heat exchange component and the discharge port.

[0024] Specifically, the kettle body is additionally arranged between the heat exchange component and the discharge port, the uncrystallized raw materials can be collected through the kettle body, the crystallization of the part of raw materials is carried out again, and the resource utilization rate is improved.

[0025] Optionally, in the direction from top to bottom, the width of the kettle body gradually decreases.

[0026] Specifically, the present application can better collect the uncrystallized raw materials by setting the kettle body to gradually decrease in width from top to bottom, thereby avoiding splashing of the materials.

[0027] Optionally, the kettle body is provided with a heat tracing coil, the heat tracing coil is provided with a second heat exchange medium inlet and a second heat exchange medium outlet, and the second heat exchange medium inlet and the second heat exchange medium outlet are communicated with the heat exchange medium feeding pipe and the heat exchange medium discharging pipe respectively.

[0028] Specifically, the present application can prevent the discharge port from being blocked by feeding appropriate amount of heat medium into the heat tracing coil during the crystallization process, and can improve the melting speed, reduce the purification time and improve the production capacity by feeding a large amount of heat medium into the heat tracing coil during the melting process.

[0029] Optionally, the shell is further provided with a grid plate for supporting the heat exchange component, the grid plate is located between the heat exchange component and the kettle body, and the upper surface of the grid plate is in abutment with the bottom end of the heat exchange component.

[0030] Specifically, the present application can support the heat exchange component through the grid plate and prevent a large amount of crystals from falling into the kettle body during the temperature rising and melting process by setting the upper surface of the grid plate in abutment with the bottom end of the heat exchange component.

[0031] In the second aspect, the present application further provides a purification system, which comprises the plate-type crystallizer.

[0032] Optionally, if the plate-type crystallizer comprises a kettle body, the purification system further comprises a material circulating pump, and the material circulating pump is communicated with the kettle body and the feeding port.

[0033] Specifically, the present application can improve the yield by feeding the uncrystallized raw materials into the plate-type crystallizer for purification again through the material circulating pump, and can effectively reduce the inclusion of impurities, further improve the product purity, reduce the melting and crystallization operation time and improve the production capacity by feeding the uncrystallized raw materials into the plate-type crystallizer through the material circulating pump during the crystallization process, so that the raw materials repeatedly wash the crystal layer attached to the surface of the heat exchange component. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the description of the embodiments or the prior art will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained according to the structures shown in the drawings without creative labor.

[0035] Figure 1 Structure diagram of the heat exchange component and the material distributor in Example 1;

[0036] Figure 2 Top view of the plate crystallizer in Example 1;

[0037] Figure 3 Side view of the plate crystallizer in Example 1;

[0038] Figure 4 Side view of the plate crystallizer in Example 2;

[0039] Figure 5 Side view of the plate crystallizer in Example 3;

[0040] Figure 6 Structure diagram of the purification system in Example 4.

[0041] Reference signs

[0042] 1-plate crystallizer, 11-shell, 111-feeding pipe, 112-distribution main pipe, 113-distribution branch pipe, 1131-notch, 114-jacket, 1141-jacket heat exchange medium inlet, 1142-jacket heat exchange medium outlet, 12-heat exchange component, 121-first heat exchange medium inlet, 122-first heat exchange medium outlet, 123-convex-concave texture layer, 13-wire mesh layer, 14-kettle body, 141-heat tracing coil, 15-grating plate, 16-liquid level meter, 17-thermometer, 18-pressure gauge, 19-gas phase balance port, 120-discharge port;

[0043] 2-cold and hot medium storage container;

[0044] 3-material circulating pump;

[0045] 4-cold and hot medium circulating pump;

[0046] 5-molten liquid storage container;

[0047] 6-raw material liquid storage container;

[0048] 7-mother liquor storage container;

[0049] 8-raw material pump. DETAILED DESCRIPTION

[0050] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0051] It should be noted that all directional indications (such as up, down, left, right, front, back, top, bottom, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directional indications will also change accordingly.

[0052] In addition, the description of "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing throughout the text is to include three parallel schemes, for example, "A and / or B" includes A scheme, or B scheme, or A and B schemes are satisfied at the same time. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of the ordinary skilled in the art, when the combination of technical solutions appears contradictory or cannot be realized, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection required by the present application.

[0053] The utility model provides a kind of plate crystallizer 1, the plate crystallizer 1 includes shell 11, shell 11 is equipped with jacket 114, jacket 114 is equipped with heat exchange medium pass-through, the upper portion of shell 11 is equipped with feed inlet, the lower portion of shell 11 is equipped with discharge outlet 120, feed inlet is communicated with raw material liquid distributor, raw material liquid distributor includes material distribution pipe network, material distribution pipe network includes with feed inlet communication feed pipe 111, with feed pipe 111 communication distribution main pipe 112 and with distribution main pipe 112 communication several distribution branch pipes 113, the bottom of distribution branch pipe 113 is equipped with several notches 1131, notch 131 is small in middle and big in both ends shape, several heat exchange components 12 are equipped between feed inlet and discharge outlet 120, all heat exchange components 12 are vertically parallel, the distance between adjacent heat exchange components 12 is 20-200mm, heat exchange component 12 is equipped with first heat exchange medium inlet 121 and first heat exchange medium outlet 122, heat exchange component 12 is one-to-one with notch 131, first heat exchange medium inlet 121 and first heat exchange medium outlet 122 are respectively communicated with heat exchange medium feed pipe and heat exchange medium discharge pipe, the surface of heat exchange component 12 is equipped with concave-convex texture layer 123, shell 11 is also equipped with grid plate 15 for supporting heat exchange component 12, grid plate 15 is located between heat exchange component 12 and kettle body 14, and the upper surface of grid plate 15 is in abutment with the bottom end of heat exchange component 12.

[0054] In another embodiment of the utility model, shell 11 is also equipped with silk screen layer 13, silk screen layer 13 is located at least one side of the upper and lower sides of heat exchange component 12, and is parallelly arranged with heat exchange component 12, and the distance between silk screen layer 13 and heat exchange component 12 is 5-60mm.

[0055] In another embodiment of the utility model, shell 11 is also equipped with kettle body 14 for storing material, kettle body 14 is located between heat exchange component 2 and discharge outlet, and gradually decreases in width along the direction from top to bottom, and is equipped with heat tracing coil 141 in kettle body 14, heat tracing coil 141 is equipped with second heat exchange medium inlet and second heat exchange medium outlet, and the second heat exchange medium inlet and second heat exchange medium outlet are respectively communicated with heat exchange medium feed pipe and heat exchange medium discharge pipe.

[0056] Another embodiment of the utility model also provides a kind of purification system, the purification system includes the plate crystallizer as described above, if plate crystallizer includes kettle body 14, the purification system also includes material circulating pump 3, and material circulating pump 3 is communicated kettle body 14 and feed inlet.

[0057] In the following description, a large number of details are discussed to provide a more thorough explanation of embodiments of the utility model, however, it is obvious to those skilled in the art that the embodiments of the utility model can be implemented without these specific details.

[0058] Embodiment 1

[0059] Referring to Figures 1 to 3 , Figures 1 to 3 is a schematic view of the structure of the plate crystallizer 1 of the present embodiment.

[0060] Referring to Figures 1 to 3 , the plate crystallizer 1 comprises a shell 11, the shell 11 is provided with a jacket 114, the jacket 114 is provided with heat exchange medium passages, i.e. a jacket heat exchange medium inlet 1141 and a jacket heat exchange medium outlet 1142. The upper portion of the shell 11 is provided with a feed inlet, the top of the shell 11 is provided with a gas phase balance port 19, and the lower portion of the shell 11 is provided with a discharge outlet 120. The feed inlet is communicated with a raw material liquid distributor, the raw material liquid distributor comprises a material distribution pipe network, the material distribution pipe network comprises a feed pipe 111 communicated with the feed inlet, a distribution main pipe 112 communicated with the feed pipe 111, and a plurality of distribution branch pipes 113 communicated with the distribution main pipe 112. All the distribution branch pipes 113 are communicated with the distribution main pipe 112 through connecting pipes with different hole diameters at equal distances. The bottom of the distribution branch pipe 13 is provided with a plurality of notches 1131, the notches 1131 are in the shape of small in the middle and large at both ends, i.e. the longitudinal section of the notches 131 is in the shape of an inverted eight.

[0061] Specifically, by providing the shell 11 with the jacket 114 and providing the jacket 114 with the heat exchange medium passages, the heat exchange medium can be introduced into the jacket 114, so that a small amount of raw material liquid adhering to the inner wall of the plate crystallizer can be crystallized and sweated at the same time during cooling crystallization and heating sweating, the uniformity of the crystal layer is ensured, and the pollution of the traditional static crystallizer wall impurities is reduced.

[0062] Referring to Figures 1 to 3 , a plurality of heat exchange components 12 are arranged between the feed inlet and the discharge outlet, all the heat exchange components 12 are arranged vertically in parallel, the distance between adjacent heat exchange components 12 is 20-200mm, and in actual production process, the distance between adjacent heat exchange components 12 can be adjusted according to actual industrial production conditions. The heat exchange component 12 is provided with a first heat exchange medium inlet 121 and a first heat exchange medium outlet 122, the heat exchange component 12 corresponds to the notch 1131 one by one, the first heat exchange medium inlet 121 and the first heat exchange medium outlet 122 are respectively communicated with a heat exchange medium feed pipe and a heat exchange medium discharge pipe, and the surface of the heat exchange component 12 is provided with a concave-convex texture layer 123. The heat exchange component 12 adopts a plate heat exchange component, and the heat exchange component 2 can be formed by expanding and adhering two stainless steel plates. The shell 11 is provided with a liquid level meter 16, a thermometer 17 and a pressure gauge 18.

[0063] Specifically, by additionally providing the concave-convex texture layer 123 on the surface of the heat exchange component 2, the crystal layer is attached to the surface of the concave-convex texture layer 123, which prevents the crystal layer from falling off from the surface of the heat exchange component 12 and causing adverse effects on purity and yield, thereby improving the purity and yield.

[0064] Please continue to see Figure 1 The shell 11 is further provided with a grid plate 15 for supporting the heat exchange component 12, the grid plate 15 is located between the heat exchange component 12 and the kettle body 14, and the upper surface of the grid plate 15 abuts against the bottom end of the heat exchange component 12.

[0065] Specifically, the embodiment can support the heat exchange component 12 through the grid plate 15, and can prevent a large amount of crystals from falling into the kettle body 14 in the process of temperature rising and melting by additionally arranging the grid plate 15 between the heat exchange component 12 and the kettle body and arranging the upper surface of the grid plate 15 to abut against the bottom end of the heat exchange component 12.

[0066] The principle of the plate-type crystallizer of the embodiment is that: by additionally arranging the notch 1131 at the bottom of the distribution branch pipe 113 and arranging the notch 1131 to have a shape of small in the middle and large at both ends, the material can be adjusted from a single strand to a uniform water curtain type multi-strand, flow through the surface of the heat exchange component 12, form a uniform crystallization layer, and make the crystal distribution more uniform. In the process of temperature reduction and crystallization and temperature rising and sweating, the heat exchange efficiency of the raw material liquid and the heat exchange medium is improved, the inclusion of impurities between the crystal layers is relatively reduced during crystallization, the inclusion of impurities and part of the crystals are effectively discharged during sweating, the crystallization and sweating effects are improved, and the purification effect of the raw material liquid is ensured.

[0067] Embodiment 2

[0068] Please see Figure 4 The difference between the embodiment and the embodiment 1 is that the shell 11 is further provided with a silk screen layer 13, the silk screen layer 13 is located at least one of the upper and lower sides of the heat exchange component 12 and is arranged in parallel with the heat exchange component 12, and the distance between the silk screen layer 13 and the heat exchange component 12 is 5-60 mm.

[0069] Specifically, the embodiment can prevent the crystal layer from having adverse effects on purity and yield during temperature rising and sweating by additionally arranging the silk screen layer 13, the silk screen layer 13 is located at least one of the upper and lower sides of the heat exchange component 12, and the silk screen layer is arranged in parallel with the heat exchange component 12, thereby improving the purity and yield. The embodiment can further prevent the crystal layer from crossing during temperature rising and sweating by arranging the distance between the silk screen layer 13 and the heat exchange component 12 to be 5-60 mm, thereby further improving the purity and yield.

[0070] Embodiment 3

[0071] Please see Figure 5The difference between the embodiment and the embodiment 2 is that the kettle body 14 for storing materials is further arranged in the shell 11, the kettle body 4 is located between the heat exchange component 2 and the discharge port, the width of the kettle body 14 gradually decreases in the direction from top to bottom, the heating coil 141 is arranged in the kettle body 14, the heating coil 141 is provided with a second heat exchange medium inlet (not shown) and a second heat exchange medium outlet (not shown), and the second heat exchange medium inlet 1411 and the second heat exchange medium outlet are respectively communicated with the heat exchange medium feeding pipe and the heat exchange medium discharging pipe.

[0072] Specifically, the embodiment can collect the uncrystallized raw materials through the kettle body 14, and crystallize the part of raw materials again, thereby improving the resource utilization rate. The embodiment can better collect the uncrystallized raw materials by arranging the kettle body 14 to gradually decrease in the width in the direction from top to bottom, thereby avoiding the splashing of materials. The embodiment can prevent the discharge port from being blocked by introducing the appropriate amount of heat medium into the heating coil 141 during the crystallization process, and can introduce a large amount of heat medium into the heating coil during the melting process, thereby improving the melting speed, reducing the purification time, and improving the production capacity.

[0073] Embodiment 4

[0074] Please refer to Figure 6 The embodiment provides a purification system, which comprises the plate crystallizer 1, the cold and hot medium storage container 2, the cold and hot medium circulating pump 4, the material circulating pump 3, the molten liquid storage container 5, the raw material liquid storage container 6, the mother liquor storage container 7 and the raw material pump 8 shown in the embodiment 3, the raw material liquid storage container 6 is communicated with the feeding port of the plate crystallizer 1, the raw material pump 8 is arranged on the communication pipeline between the raw material liquid storage container 6 and the feeding port of the plate crystallizer 1, the cold and hot medium storage container 2 is communicated with the heat exchange medium feeding pipe and the heat exchange medium discharging pipe of the plate crystallizer 1, the cold and hot medium circulating pump 4 is arranged on the communication pipeline between the cold and hot medium storage container 2 and the heat exchange medium feeding pipe of the plate crystallizer 1, the discharge port of the plate crystallizer 1 is communicated with the molten liquid storage container 5, the raw material liquid storage container 6 and the mother liquor storage container 7, the kettle body 14 of the plate crystallizer 1 is communicated with the feeding port, and the material circulating pump 2 is arranged on the communication pipeline between the kettle body 14 and the feeding port.

[0075] Specifically, the embodiment can send the uncrystallized raw materials into the plate crystallizer 1 again for purification through the material circulating pump 3, so as to improve the yield; meanwhile, the uncrystallized raw materials are sent into the plate crystallizer 1 through the material circulating pump 3 during the crystallization process, and the raw materials repeatedly wash the crystal layers adhered to the surface of the heat exchange components, so that the inclusion of impurities can be effectively reduced, the product purity can be further improved, the melting and crystallization operation time can be reduced, and the production capacity can be improved.

[0076] The above embodiment only illustrates the principle and effect of the present application, and is not used to limit the present application. Any person skilled in the art can modify or change the above embodiment without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical concept disclosed by the present application should be covered by the claims of the present application.

Claims

1. A plate crystallizer, characterized by The plate crystallizer comprises a shell, an upper portion of the shell is provided with a feed inlet, a lower portion of the shell is provided with a discharge outlet, the feed inlet is communicated with a raw material liquid distributor, the raw material liquid distributor comprises a material distribution pipe network, the material distribution pipe network comprises a feed pipe communicated with the feed inlet, a distribution main pipe communicated with the feed pipe, and a plurality of distribution branch pipes communicated with the distribution main pipe, the bottom of the distribution branch pipe is provided with a plurality of notches, the notches are in the shape of small in the middle and large at both ends, a plurality of heat exchange components are arranged in the shell, all the heat exchange components are arranged in parallel along the transverse direction, the heat exchange components are provided with a first heat exchange medium inlet and a first heat exchange medium outlet, the heat exchange components correspond to the notches one by one, the first heat exchange medium inlet and the first heat exchange medium outlet are respectively communicated with a heat exchange medium feeding pipe and a heat exchange medium discharging pipe.

2. The panel crystallizer of claim 1, wherein, The shell is provided with a jacket, and the jacket is provided with a heat exchange medium passage.

3. The panel crystallizer of claim 1, wherein, The surface of the heat exchange component is provided with a concave-convex texture layer.

4. The panel crystallizer of claim 1, wherein, The shell is further provided with a wire mesh layer, the wire mesh layer is arranged on at least one side of the upper and lower sides of the heat exchange component, and is arranged in parallel with the heat exchange component. The distance between adjacent heat exchange components is 20-200 mm.

5. The panel crystallizer of claim 4, wherein, The distance between the wire mesh layer and the heat exchange component is 5-60 mm.

6. The panel crystallizer of claim 1, wherein, The shell is further provided with a kettle body for storing material, and the kettle body is located between the heat exchange component and the discharge outlet.

7. The panel crystallizer of claim 6, wherein, The width of the kettle body gradually decreases in the direction from top to bottom.

8. The panel crystallizer of claim 6, wherein, The kettle body is provided with a heat tracing coil, the heat tracing coil is provided with a second heat exchange medium inlet and a second heat exchange medium outlet, the second heat exchange medium inlet and the second heat exchange medium outlet are respectively communicated with the heat exchange medium feeding pipe and the heat exchange medium discharging pipe. The shell is further provided with a grid plate for supporting the heat exchange component, the grid plate is located between the heat exchange component and the kettle body, and the upper surface of the grid plate abuts against the bottom end of the heat exchange component.

9. A purification system, characterized in that, The purification system comprises the plate crystallizer according to any one of claims 1-8.

10. The purification system of claim 9, wherein, If the plate crystallizer comprises a kettle body, the purification system further comprises a material circulating pump, and the material circulating pump is communicated with the kettle body and the feed inlet.

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