Continuous crystallization device for rebaudioside N

Abstract

The utility model discloses a continuous crystallization device for rebaudioside N. The continuous crystallization device comprises a batching system, a continuous crystallization system, a solid-liquid separation system and a drying system which are communicated, the batching system comprises a batching tank, and a steam coil pipe is arranged in a jacket of the batching tank; the continuous crystallization system comprises at least three crystallization tanks which are connected in series; the jacket of each crystallizing tank is communicated with a condensate water pipeline, and a temperature sensor is arranged in each crystallizing tank; the solid-liquid separation system comprises a buffer tank and a centrifugal machine which are communicated with the continuous crystallization system, a first liquid level sensor is arranged in the buffer tank, and a first electric valve is arranged on a connecting pipeline of the buffer tank and the centrifugal machine; the drying system comprises a drying tank connected with a solid outlet of the centrifugal machine, and the drying tank communicates with a finished product storage tank. The crystallization device is high in automation degree, continuous crystallization of rebaudioside N is realized through continuous feeding and continuous discharging, the crystallization efficiency is high, the production efficiency of products is greatly improved, and the utilization rate of crystallization mother liquor is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of crystallization devices, in particular to a continuous crystallization device for rebaudioside N. Background Art

[0002] Rebaudioside N is a steviol glycoside extracted from stevia leaves. When preparing rebaudioside N, it is usually necessary to crystallize and purify the crude product. At present, most of the crystallization processes used in my country are batch crystallization. This type of crystallization method is intermittent cooling treatment, with low production efficiency, low utilization rate of crystallization mother liquor, low process capacity, high cost, strong human intervention, and different crystal quality of each batch. In order to solve the above technical problems, it is necessary to provide a continuous crystallization device with high production efficiency. Utility Model Content

[0003] The technical problem to be solved by the utility model is: in view of the shortcomings of the prior art, a continuous crystallization device for rebaudioside N is provided. The crystallization device has a high degree of automation and realizes the continuous crystallization of rebaudioside N through continuous feeding and continuous discharging. The crystallization efficiency is high, the production efficiency of the product is greatly improved, and the utilization rate of the crystallization mother liquor is improved.

[0004] In order to solve the above technical problems, the technical solution of the utility model is:

[0005] A continuous crystallization device for rebaudioside N, comprising a batching system, a continuous crystallization system, a solid-liquid separation system and a drying system connected to each other;

[0006] The batching system comprises at least two batching tanks, and the jackets of the batching tanks are provided with steam coils;

[0007] The continuous crystallization system comprises at least three crystallization tanks connected in series; the jackets of each crystallization tank are connected to a condensed water pipeline, each crystallization tank is provided with a temperature sensor, the temperature of each crystallization tank connected in series decreases sequentially during crystallization, the feeding mode of the crystallization tank is top feeding and bottom discharging, and a feed pump is provided at the feed port of the crystallization tank;

[0008] The solid-liquid separation system comprises a buffer tank and a centrifuge connected to the continuous crystallization system, a first liquid level sensor is arranged in the buffer tank, a first electric valve is arranged on the connecting pipe between the buffer tank and the centrifuge, and the first liquid level sensor is interlocked with the first electric valve;

[0009] The drying system comprises a drying tank connected to the solid outlet of the centrifuge, and the drying tank is connected to the finished product storage tank.

[0010] As a preferred embodiment of the above technical solution, a stirrer is provided in the batching tank, the crystallization tank and the drying tank.

[0011] As a preferred embodiment of the above technical solution, the liquid outlet of the centrifuge is also connected to a mother liquid recovery tank.

[0012] As a preferred embodiment of the above technical solution, the batching tank is connected to the crystallization tank through a pipeline and a valve.

[0013] As a preferred embodiment of the above technical solution, a scraping mechanism is also provided on the agitator in each crystallization tank, and the scraping mechanism includes an auxiliary stirring rod connected to the agitator and a scraper arranged at the end of the auxiliary stirring rod and abutting against the inner wall of the tank body.

[0014] As a preferred embodiment of the above technical solution, the continuous crystallization system includes four crystallization tanks connected in series, namely a first crystallization tank, a second crystallization tank, a third crystallization tank, and a fourth crystallization tank.

[0015] As a preferred embodiment of the above technical solution, the fourth crystallization tank is also connected to a seed storage tank.

[0016] As a preferred embodiment of the above technical solution, there are two batching tanks, namely a first batching tank and a second batching tank. The first batching tank and the second batching tank are both connected to the first crystallization tank. A second electric valve and a third electric valve are respectively provided on the pipelines connecting the first batching tank and the second batching tank with the first crystallization tank; a second liquid level sensor and a third liquid level sensor are respectively provided in the first batching tank and the second batching tank, and the second liquid level sensor and the third liquid level sensor are respectively interlocked with the second electric valve and the third electric valve.

[0017] As a preferred embodiment of the above technical solution, a fourth liquid level sensor, a fifth liquid level sensor, a sixth liquid level sensor and a seventh liquid level sensor are respectively provided in the first crystallizer, the second crystallizer, the third crystallizer and the fourth crystallizer, and a fourth electric valve, a fifth electric valve, a sixth electric valve and a seventh electric valve are respectively provided on the discharge pipe of the first crystallizer, the discharge pipe of the second crystallizer, the discharge pipe of the third crystallizer and the discharge pipe of the fourth crystallizer; the fourth liquid level sensor is interlocked with the fourth electric valve, the fifth liquid level sensor is interlocked with the fifth electric valve, the sixth liquid level sensor is interlocked with the sixth electric valve, and the sixth liquid level sensor is interlocked with the sixth electric valve.

[0018] Due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0019] The utility model provides a continuous crystallization device for rebaudioside N, comprising a connected batching system, a continuous crystallization system, a solid-liquid separation system and a drying system. The device performs continuous gradient cooling crystallization treatment on a crystallization mother liquor, thereby greatly improving the crystallization efficiency and utilization rate of the crystallization mother liquor while ensuring product quality.

[0020] The continuous crystallization system of the device includes a plurality of crystallization tanks connected in series, the temperatures of the plurality of crystallization tanks are lowered in sequence, and during crystallization, the continuous crystallization system is for continuous feeding and continuous discharging, thereby realizing continuous gradient cooling crystallization of the crystallization mother liquor and improving the production efficiency of the product.

[0021] The device has two batching tanks, namely the first batching tank and the second batching tank. The first batching tank and the second batching tank are both connected to the continuous crystallization system. The pipelines connecting the first batching tank and the second batching tank to the continuous crystallization system are respectively provided with a second electric valve and a third electric valve; the first batching tank and the second batching tank are respectively provided with a second liquid level sensor and a third liquid level sensor, and the second liquid level sensor and the third liquid level sensor are respectively interlocked with the second electric valve and the third electric valve. The above settings can not only realize the automatic unloading of the crystallization mother liquor, but also control the opening of the first batching tank or the second batching tank according to the amount of material in the first batching tank or the second batching tank, thereby improving the product capacity.

[0022] The device is provided with a scraper at the end of an auxiliary stirring rod and against the inner wall of the tank on the stirrer in the continuous crystallization system. The auxiliary stirring rod and the scraper rotate under the drive of the stirrer, and the material adhering to the crystallization tank can be scraped off while stirring the material, thereby improving the product yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0024] Figure 1 It is a structural schematic diagram of an embodiment of the utility model;

[0025] Figure 2 Schematic diagram of the internal structure of the first batching tank in the embodiment;

[0026] In the figure, 1, steam coil; 2, first batching tank; 3, second batching tank; 4, second electric valve; 5, third electric valve; 6, second liquid level sensor; 7, third liquid level sensor; 8, condensate pipe; 9, temperature sensor; 10, first crystallization tank; 11, second crystallization tank; 12, third crystallization tank; 13, fourth crystallization tank; 14, buffer tank; 15, centrifuge; 16, first liquid level sensor; 17, first electric valve; 18, mother liquor recovery tank; 19, drying tank; 20, finished product storage tank; 21, agitator; 22, feed pump; 23, auxiliary stirring rod; 24, scraper; 25, seed storage tank; 26, fourth electric valve; 27, fifth electric valve; 28, sixth electric valve; 29, seventh electric valve. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0028] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0029] It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0030] Example

[0031] like Figure 1 and Figure 2 As shown, a continuous crystallization device for rebaudioside N includes a batching system, a continuous crystallization system, a solid-liquid separation system and a drying system connected to each other;

[0032] The batching system comprises at least one batching tank, and a steam coil 1 is arranged in the jacket of the batching tank.

[0033] Specifically, in the present embodiment, there are two batching tanks, namely a first batching tank 2 and a second batching tank 3. The first batching tank 2 and the second batching tank 3 are both connected to the continuous crystallization system. A second electric valve 4 and a third electric valve 5 are respectively provided on the pipelines connecting the first batching tank 2 and the second batching tank 3 with the continuous crystallization system; a second liquid level sensor 6 and a third liquid level sensor 7 are respectively provided in the first batching tank 2 and the second batching tank 3. The second liquid level sensor 6 and the third liquid level sensor 7 are respectively interlocked with the second electric valve 4 and the third electric valve 5. In actual use, the first batching tank 2 and the second batching tank 3 are used to prepare the crystallization mother liquor. The crystallization mother liquor in the first batching tank 2 enters the crystallization system at a certain flow rate for cooling and crystallization. If the second liquid level sensor 6 in the first batching tank 2 detects that the crystallization mother liquor in the first batching tank 2 has completely flowed out, it transmits a signal to the external control system (not shown in the figure), and the external control system automatically closes the second electric valve 4 and opens the third electric valve 5. The crystallization mother liquor in the second batching tank 3 enters the crystallization system to continue the crystallization treatment, thereby realizing the continuous production of rebaudioside N and improving its yield.

[0034] The continuous crystallization system comprises at least three crystallization tanks connected in series; the jackets of the crystallization tanks are connected to the condensed water pipeline 8, and the temperature sensors 9 are arranged in the crystallization tanks.

[0035] Specifically, in the present embodiment, the continuous crystallization system includes four crystallization tanks connected in series, namely, the first crystallization tank 10, the second crystallization tank 11, the third crystallization tank 12, and the fourth crystallization tank 13; the temperature in the first crystallization tank 10, the second crystallization tank 11, the third crystallization tank 12, and the fourth crystallization tank 13 is reduced successively. The feed inlet of the first crystallization tank 10, the second crystallization tank 11, the third crystallization tank 12, and the fourth crystallization tank 13 is provided with a feed pump 22, and the feed speed is controlled by adjusting the speed of the feed pump. The crystallization mother liquor in the first batching tank 2 or the second batching tank 3 flows through the first crystallization tank 10, the second crystallization tank 11, the third crystallization tank 12, and the fourth crystallization tank 13 at a certain flow rate, and performs continuous staged cooling crystallization treatment, which not only improves the crystallization efficiency, but also ensures the quality of the product. The second crystallization tank 12 is also connected to a seed storage tank 25.

[0036] In the present embodiment, a fourth liquid level sensor (not shown in the figure), a fifth liquid level sensor (not shown in the figure), a sixth liquid level sensor (not shown in the figure), and a seventh liquid level sensor (not shown in the figure) are respectively provided in the first crystallizer 10, the second crystallizer 11, the third crystallizer 12, and the fourth crystallizer 13; a fourth electric valve 26, a fifth electric valve 27, a sixth electric valve 28, and a seventh electric valve are respectively provided on the discharge pipe of the first crystallizer 10, the discharge pipe of the second crystallizer 11, the discharge pipe of the third crystallizer 12, and the discharge pipe of the fourth crystallizer 13; the fourth liquid level sensor and the fourth electric valve 26, the fifth liquid level sensor and the fifth electric valve 27, the sixth liquid level sensor and the sixth electric valve 28, and the sixth liquid level sensor and the sixth electric valve 28 are interlocked.

[0037] Through the above arrangement, during the specific continuous gradient crystallization, the mother liquor of Rebaudioside N first enters the first crystallization tank 10. When the fourth liquid level sensor detects that the first crystallization tank 10 is full of the mother liquor of Rebaudioside N, a signal is sent to the external control system (not shown in the figure). The external control system controls the opening of the fourth electric valve 26 to start feeding into the second crystallization tank 11. The operation is carried out in sequence until the fourth crystallization tank 13 is full of liquid. Then, the seventh liquid level sensor transmits a signal to the external control system, and the external control system automatically opens the seventh electric valve to discharge the material.

[0038] The solid-liquid separation system includes a buffer tank 14 and a centrifuge 15 connected to the continuous crystallization system. A first liquid level sensor 16 is provided in the buffer tank 14. A first electric valve 17 is provided on the connecting pipe between the buffer tank 14 and the centrifuge 15. The first liquid level sensor 16 is interlocked with the first electric valve 17. The discharge of the fourth crystallization tank 13 enters the buffer tank 14 for temporary storage. When the first liquid level sensor 16 detects that the height of the liquid in the buffer tank 14 reaches the set value, the signal is transmitted to the external control system, and the external control system opens the first electric valve 17, and the liquid enters the centrifuge 15 for centrifugal treatment.

[0039] In this embodiment, the liquid outlet of the centrifuge 15 is connected to the mother liquid recovery tank 18, and the solid outlet of the centrifuge 15 is connected to the drying tank 19 and the finished product storage tank 20 in sequence. The liquid after centrifugation contains a large amount of rebaudioside O, which enters the mother liquid recovery tank 18 for collection and is used to prepare rebaudioside O. The solid obtained after centrifugation is dried in the drying tank 19 to obtain rebaudioside N, and enters the finished product storage tank 20 for temporary storage.

[0040] In this embodiment, the first batching tank 2, the second batching tank 3, the first crystallization tank 10, the second crystallization tank 11, the third crystallization tank 12, the fourth crystallization tank 13 and the drying tank 19 are all provided with an agitator 21, and the heat exchange efficiency is improved under the action of the agitator 21, thereby improving the product production efficiency.

[0041] In this embodiment, the first batching tank 2 and the second batching tank 3 are both connected to the first crystallization tank 10 through pipelines, and the crystallization mother liquor is transported to the crystallization tank for cooling and crystallization treatment under the action of the material delivery pump 22.

[0042] In this embodiment, a scraping mechanism is further provided on the agitator 21 in the first crystallization tank 10, the second crystallization tank 11, the third crystallization tank 12, and the fourth crystallization tank 13, and the scraping mechanism includes an auxiliary stirring rod 23 connected to the agitator 21 and a scraper 24 disposed at the end of the auxiliary stirring rod 23 and abutting against the inner wall of the tank body. The auxiliary stirring rod 23 and the scraper 24 rotate under the drive of the agitator 21, and the material adhering to the inner wall of the tank body can also be scraped off under the premise of stirring the material, thereby improving the product yield.

[0043] In addition, it should be understood that after reading the contents taught in the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. A continuous crystallization device for rebaudioside N, characterized in that: It includes a connected batching system, a continuous crystallization system, a solid-liquid separation system and a drying system; The batching system comprises at least two batching tanks, and the jackets of the batching tanks are provided with steam coils; The continuous crystallization system comprises at least three crystallization tanks connected in series; the jackets of each crystallization tank are connected to a condensed water pipeline, each crystallization tank is provided with a temperature sensor, the temperature of each crystallization tank connected in series decreases sequentially during crystallization, the feeding mode of the crystallization tank is top feeding and bottom discharging, and a feed pump is provided at the feed port of the crystallization tank; The solid-liquid separation system comprises a buffer tank and a centrifuge connected to the continuous crystallization system, a first liquid level sensor is arranged in the buffer tank, a first electric valve is arranged on the connecting pipe between the buffer tank and the centrifuge, and the first liquid level sensor is interlocked with the first electric valve; The drying system comprises a drying tank connected to the solid outlet of the centrifuge, and the drying tank is connected to the finished product storage tank.

2. A continuous crystallization device for rebaudioside N according to claim 1, characterized in that: Agitators are installed in the batching tank, crystallization tank and drying tank.

3. A continuous crystallization device for rebaudioside N according to claim 1, characterized in that: The liquid outlet of the centrifuge is also connected to a mother liquid recovery tank.

4. A continuous crystallization device for rebaudioside N according to claim 1, characterized in that: The batching tank is connected with the crystallization tank through pipelines and valves.

5. A continuous crystallization device for rebaudioside N according to claim 1, characterized in that: A scraping mechanism is also provided on the stirrer in each crystallization tank. The scraping mechanism comprises an auxiliary stirring rod connected to the stirrer and a scraper arranged at the end of the auxiliary stirring rod and abutting against the inner wall of the crystallization tank.

6. A continuous crystallization device for rebaudioside N according to claim 1, characterized in that: The continuous crystallization system comprises four crystallization tanks connected in series, namely a first crystallization tank, a second crystallization tank, a third crystallization tank and a fourth crystallization tank.

7. A continuous crystallization device for rebaudioside N according to claim 6, characterized in that: The second crystallization tank is also connected to a seed crystal storage tank.

8. A continuous crystallization device for rebaudioside N according to claim 6, characterized in that: There are two batching tanks, namely the first batching tank and the second batching tank. The first batching tank and the second batching tank are both connected to the first crystallization tank. The pipelines connecting the first batching tank, the second batching tank and the first crystallization tank are respectively provided with a second electric valve and a third electric valve; the first batching tank and the second batching tank are respectively provided with a second liquid level sensor and a third liquid level sensor, and the second liquid level sensor and the third liquid level sensor are respectively interlocked with the second electric valve and the third electric valve.

9. A continuous crystallization device for rebaudioside N according to claim 6, characterized in that: A fourth liquid level sensor, a fifth liquid level sensor, a sixth liquid level sensor and a seventh liquid level sensor are respectively arranged in the first crystallization tank, the second crystallization tank, the third crystallization tank and the fourth crystallization tank; a fourth electric valve, a fifth electric valve, a sixth electric valve and a seventh electric valve are respectively arranged on the discharge pipe of the first crystallization tank, the discharge pipe of the second crystallization tank, the discharge pipe of the third crystallization tank and the discharge pipe of the fourth crystallization tank; the fourth liquid level sensor is interlocked with the fourth electric valve, the fifth liquid level sensor is interlocked with the fifth electric valve, the sixth liquid level sensor is interlocked with the sixth electric valve, and the sixth liquid level sensor is interlocked with the sixth electric valve.

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