A separation device for chitin fiber production

Abstract

This invention discloses a separation device for chitin fiber production, comprising a separation tank internally divided into an upper pretreatment zone and a lower deep treatment zone. A first filter and a second filter are installed in both zones. A rotating shaft is mounted on the separation tank, with stirring paddles mounted on it. A drive motor is connected to the shaft. The upper pretreatment zone and the lower deep treatment zone are connected via a first discharge cylinder, and a second discharge cylinder is also connected to the separation tank. A waste liquid discharge pipe connects to the upper pretreatment zone, and a fresh liquid inlet pipe connects to the lower deep treatment zone. The lower deep treatment zone is connected to the upper pretreatment zone via a circulation pipe, which is equipped with a first delivery pump. This invention reduces the amount of fresh chemicals used and lowers production costs by dividing the separation tank into an upper pretreatment zone and a lower deep treatment zone. Fresh, high-concentration acid / alkali is added to the lower deep treatment zone for reaction, and the residual acid / alkali is used in the upper pretreatment zone.

Description

Technical Field

[0001] This utility model relates to the field of chitin fiber processing technology, specifically to a separation device for chitin fiber production. Background Technology

[0002] Chitosan is a natural high-molecular-weight polysaccharide widely found in the exoskeletons of crustaceans such as shrimp and crabs, insect epidermis, and fungal cell walls. Its main component is chitosan, and it possesses biodegradability, biocompatibility, adsorption properties, casting properties, and filamentation properties. Chitosan has a wide range of applications, including in the industrial production of fabrics, clothing, dyes, paper, and water treatment. Chitosan fiber, in particular, utilizes the casting and filamentation properties of chitosan through a wet spinning process to produce fibers with high strength and elongation.

[0003] When extracting chitin using the acid-base method, hydrochloric acid and sodium hydroxide are used to remove calcium carbonate and protein from shrimp or crab shells, respectively. This requires a single-tank, step-by-step process (e.g., acid washing to remove calcium, followed by alkali boiling to remove protein). During the soaking and separation process, fresh hydrochloric acid and sodium hydroxide are discharged after being used only once, resulting in residual acid / alkali still having a certain degree of activity and being treated as waste liquid, causing chemical waste and increasing production costs. Summary of the Invention

[0004] The main objective of this invention is to overcome the defects of the prior art and provide a separation device for the production of chitin fibers.

[0005] To achieve the above objectives, the present invention proposes a separation device for chitin fiber production, comprising a separation tank. The interior of the separation tank is divided into an upper pretreatment zone and a lower deep treatment zone by a partition plate. A feeding port is provided at the top of the separation tank. A first filter screen and a second filter screen are respectively provided in the upper pretreatment zone and the lower deep treatment zone. A rotating shaft is provided on the central axis of the separation tank. A stirring paddle corresponding to the upper pretreatment zone and the lower deep treatment zone is respectively provided on the rotating shaft. A drive motor is connected to one end of the rotating shaft. The upper pretreatment zone and the lower deep treatment zone are connected by a first discharge cylinder. A second discharge cylinder is connected to the bottom of the separation tank. A first valve and a second valve are respectively provided at the outlets of the first discharge cylinder and the second discharge cylinder. A waste liquid discharge pipe is connected to the bottom of the upper pretreatment zone. A fresh liquid inlet pipe is connected to the upper part of the lower deep treatment zone. The lower part of the lower deep treatment zone is connected to the upper part of the upper pretreatment zone through a circulation pipe. A first conveying pump is provided on the circulation pipe.

[0006] To further optimize the technical solution, the bottom of the partition plate and the separation tank are both designed as conical bottom structures. The first filter screen and the second filter screen are both conical filter screens. A first gap space is provided between the first filter screen and the partition plate. The waste liquid discharge pipe is connected to the first gap space. A second gap space is provided between the second filter screen and the bottom of the separation tank. The lower end of the circulation pipe is connected to the second gap space.

[0007] The technical solution is further optimized by connecting the top inlet of the first discharge cylinder to the lowest point of the first filter screen, and connecting the top inlet of the second discharge cylinder to the lowest point of the second filter screen. The shaft body is provided with two spiral blades corresponding to the first discharge cylinder and the second discharge cylinder, respectively. The two spiral blades extend from the inside of the first discharge cylinder and the second discharge cylinder to the top of the filter screen.

[0008] To further optimize the technical solution, the stirring paddle is an anchor-frame type stirring paddle, and the bottom of the anchor frame of the stirring paddle is set as an arc-shaped frame structure corresponding to the conical bottom of the first filter screen or the second filter screen.

[0009] The technical solution is further optimized by connecting a first four-way valve to the circulation pipe, and the new liquid inlet pipe is connected to the circulation pipe through the first four-way valve. A third valve and a fourth valve are respectively provided at the two horizontal interfaces of the first four-way valve, and a fifth valve and a sixth valve are respectively provided at the two vertical direct interfaces of the first four-way valve.

[0010] The technical solution is further optimized by connecting a second four-way valve to the circulation pipe, and connecting the waste liquid discharge pipe to the circulation pipe through the second four-way valve. The two horizontal interfaces of the second four-way valve are respectively provided with a seventh valve and an eighth valve. The vertical direct port at one end of the second four-way valve is connected to the vertical direct port at one end of the first four-way valve. A ninth valve is provided at the vertical direct port at the other end of the second four-way valve. The waste liquid discharge pipe is connected to a second delivery pump.

[0011] To further optimize the technical solution, the circulation tube is equipped with a first online pH meter and a second online pH meter.

[0012] To further optimize the technical solution, a third delivery pump is connected to the new liquid inlet pipe, and the inlet end of the third delivery pump is connected to a new acid pipe and a new alkali pipe respectively. A tenth valve is provided on the new acid pipe, and an eleventh valve is provided on the new alkali pipe.

[0013] To further optimize the technical solution, the sidewall of the separation tank is designed as a sandwich structure.

[0014] To further optimize the technical solution, a hopper is provided at the feeding port.

[0015] The beneficial effects of this invention include: by dividing the separation tank into an upper pretreatment zone and a lower deep treatment zone, fresh high-concentration acid / alkali is added to the lower deep treatment zone through the new liquid inlet pipe. After the reaction, the filtrate obtained by filtering through the second filter screen is pumped back to the upper pretreatment zone through the circulation pipe and the first transfer pump. The residual acid / alkali (pH 2-3 or 10-11) is used for pre-decalcification or pre-deproteinization. The raw material after pre-decalcification or pre-deproteinization is then fed into the lower deep treatment zone through the first discharge cylinder to continue the deep reaction, ensuring thorough separation. By making full use of chemical reagents in stages, the amount of fresh chemicals used is reduced, thereby reducing production costs. Attached Figure Description

[0016] Figure 1 This is an overall schematic diagram of the separation device used for chitin fiber production in an embodiment of this utility model.

[0017] Figure 2 This is a schematic diagram of the interior of the separator after it has been cut open in an embodiment of this utility model.

[0018] Figure 3 This is a schematic diagram showing the connection of the first filter screen, the second filter screen, and the stirring paddle in an embodiment of this utility model.

[0019] Figure reference numerals: 1 Separation tank; 101 Upper pretreatment zone; 102 Lower deep treatment zone; 103 Feed port; 104 First gap space; 105 Second gap space; 106 Sandwich structure; 107 Feed hopper; 2 Separator plate; 3 First filter screen; 4 Second filter screen; 5 Rotating shaft; 6 Drive motor; 7 First discharge cylinder; 701 First valve; 8 Second discharge cylinder; 801 Second valve; 9 Waste liquid discharge pipe; 10 Fresh liquid inlet pipe; 11 Circulation pipe; 12 First... 1. Transfer pump; 13. Agitator; 131. Arc-shaped frame structure; 14. Spiral blade; 15. First four-way valve; 16. Third valve; 17. Fourth valve; 18. Fifth valve; 19. Sixth valve; 20. Second four-way valve; 21. Seventh valve; 22. Eighth valve; 23. Ninth valve; 24. Second transfer pump; 25. First online pH meter; 26. Second online pH meter; 27. Third transfer pump; 28. New acid pipe; 29. ​​New alkali pipe; 30. Tenth valve; 31. Eleventh valve. Detailed Implementation

[0020] To make the technical problems, technical solutions, and beneficial effects of the embodiments of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0021] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component. Furthermore, a connection can be for both fixing and circuit connection purposes.

[0022] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] Please see Figures 1 to 3One embodiment of the separation device for chitin fiber production includes a separation tank 1, which is divided into an upper pretreatment zone 101 and a lower deep treatment zone 102 by a partition plate 2. A feeding port 103 is provided at the top of the separation tank 1. A first filter screen 3 and a second filter screen 4 are respectively provided in the lower parts of the upper pretreatment zone 101 and the lower deep treatment zone 102. A rotating shaft 5 is provided on the central axis of the separation tank 1, with its two ends extending through the bottom and top surfaces of the separation tank 1, respectively. A stirring paddle 13 corresponding to the upper pretreatment zone 101 and the lower deep treatment zone 102 is provided on the rotating shaft 5. A drive motor 6 is connected to the top of the rotating shaft 5. Communication is established between the upper pretreatment zone 101 and the lower deep treatment zone 102. The first discharge cylinder 7 is connected to the bottom of the separation tank 1, and the second discharge cylinder 8 is connected to the bottom of the separation tank 1. The first valve 701 and the second valve 801 are respectively provided at the outlet of the first discharge cylinder 7 and the second discharge cylinder 8. The first valve 701 and the second valve 801 are used to control the opening and closing of the discharge channels of the first discharge cylinder 7 and the second discharge cylinder 8. The waste liquid discharge pipe 9 is connected to the bottom of the upper pretreatment zone 101, and the new liquid inlet pipe 10 is connected to the upper part of the lower deep treatment zone 102. The new liquid inlet pipe 10 is connected to the external acid or alkali tank for adding fresh acid or alkali to the lower deep treatment zone 102. The lower part of the lower deep treatment zone 102 is connected to the upper part of the upper pretreatment zone 101 through the circulation pipe 11. The first conveying pump 12 is provided on the circulation pipe 11. Specifically, a hopper 107 is provided at the feeding port 103. External chitin raw materials are guided through the hopper 107 and fed into the upper pretreatment zone 101 of the separator 1 for pretreatment. The bottom of both the partition plate 2 and the separator 1 is a conical bottom structure. The first filter screen 3 and the second filter screen 4 are both conical filters. By using conical filters, the effective filtration area of ​​the filter screen can be increased, and the inclination angle of the cone can make the filter residue containing chitin more likely to gather and be discharged to the bottom of the cone under the action of gravity. A first gap space 104 is provided between the first filter screen 3 and the partition plate 2. The waste liquid discharge pipe 9 is connected to the first gap space. Space 104 is connected. When the upper pretreatment zone 101 is soaking and separating the calcium carbonate or protein in the chitin raw material (crab shell or shrimp shell), the filtrate after being filtered by the first filter screen 3 is collected in the first gap space 104 and discharged to the outside of the separation tank 1 through the waste liquid discharge pipe 9. Similarly, a second gap space 105 is provided between the second filter screen 4 and the bottom of the separation tank 1. The lower end of the circulation pipe 11 is connected to the second gap space 105. The filtrate after being filtered by the second filter screen 4 is collected in the second filter screen 4 and transported back to the upper pretreatment zone 101 for reuse through the circulation pipe 11 and the first transfer pump 12.

[0025] In this embodiment, a separation tank 1 is divided into an upper pretreatment zone 101 and a lower deep treatment zone 102. Fresh, high-concentration acid / alkali is added to the lower deep treatment zone 102 through the new liquid inlet pipe 10. After the reaction, the filtrate obtained by filtering through the second filter screen 4 is pumped back to the upper pretreatment zone 101 via the circulation pipe 11 and the first transfer pump 12. The residual acid / alkali (pH 2-3 or 10-11) is used for pre-decalcification or pre-deproteinization. The raw material after pre-decalcification or pre-deproteinization then enters the lower deep treatment zone through the first discharge cylinder 7. 102 continues the deep reaction to ensure thorough separation; that is, the upper pretreatment zone 101 uses the filtrate returned from the lower deep treatment zone 102 to perform preliminary demineralization or deproteinization of the raw materials, while the lower deep treatment zone 102 uses fresh high-concentration acid / alkali for reaction. By making full use of chemical reagents in stages, the amount of fresh chemicals used is reduced, thus lowering costs. At the same time, the pretreatment and deep treatment are integrated into a separation tank 1, sharing a drive motor 6 and a rotating shaft 5 to drive the double stirring paddles 13, effectively reducing the equipment footprint and investment costs.

[0026] In a specific example, the top inlet of the first discharge cylinder 7 is connected to the lowest point of the first filter screen 3, and the top inlet of the second discharge cylinder 8 is connected to the lowest point of the second filter screen 4. The filter residue is naturally slid towards the discharge port using the principle of gravity-driven self-discharge. The shaft 5 is equipped with two spiral blades 14 corresponding to the first discharge cylinder 7 and the second discharge cylinder 8, respectively. The two spiral blades 14 extend from the inside of the first discharge cylinder 7 and the second discharge cylinder 8 to the top of the filter screen. During slag discharge, the drive motor 6 reverses the rotation of the shaft 5, and the spiral blades 14 push the residue into the first discharge cylinder 7 or the second discharge cylinder 8. The filter residue in the barrel 8 moves downward and is discharged quickly (e.g., the raw material residue containing chitin after pre-decalcification in the upper layer is discharged to the lower layer) to prevent the discharge port from being blocked. When soaking and stirring for decalcification or deproteinization, the drive motor 6 drives the rotating shaft 5 to rotate forward, and the spiral blades 14 and the stirring paddle 13 rotate forward synchronously to stir and form an axial and radial mixed flow field, ensuring that the material in the upper pre-decalcification / deproteinization stage is fully mixed with the circulating filtrate (weak acid / weak alkali) to improve the uniformity of the reaction. Similarly, the spiral blades 14 and the stirring paddle 13 in the lower layer work together with high concentration of fresh acid / alkali to accelerate the deep reaction and shorten the total reaction cycle.

[0027] In a specific example, the agitator 13 is an anchor-frame agitator. The bottom of the anchor frame of the agitator 13 is set as an arc-shaped frame structure 131 corresponding to the cone bottom of the first filter screen 3 or the second filter screen 4. That is, the arc-shaped outline of the arc-shaped frame structure 131 is consistent with the inclination angle of the cone bottom of the filter screen. When the agitator 13 rotates forward to agitate, the arc-shaped frame structure 131 continuously scrapes the surface of the filter screen to prevent protein or calcium carbonate particles from caking and clogging on the filter screen, and maintains the smooth seepage of the filtrate. When discharging slag, it can push the filter slag along the inclined surface to the discharge port (the top inlet of the first discharge cylinder 7 and the second discharge cylinder 8) to avoid the problem of material accumulation caused by the failure of gravity slag discharge.

[0028] In a preferred embodiment, a first four-way valve 15 is connected to the circulation pipe 11. The new liquid inlet pipe 10 is vertically connected to the circulation pipe 11 through the first four-way valve 15. A third valve 16 and a fourth valve 17 are respectively provided at the two horizontal interfaces of the first four-way valve 15, and a fifth valve 18 and a sixth valve 19 are respectively provided at the two vertical interfaces of the first four-way valve 15. When adding fresh acid or alkali to the lower deep treatment zone 102, the third valve 16 and the fourth valve 17 are opened, and the fifth valve 18 and the sixth valve 19 are closed. When the filtrate after reaction in the lower deep treatment zone 102 is transported to the upper pretreatment zone 101 for pretreatment, the fifth valve 18 and the sixth valve 19 are opened, and the third valve 16 and the fourth valve 17 are closed. When the lower deep treatment zone 102 is reacting, the third valve 16 and the fifth valve 18 are opened, and the fourth valve 17 and the sixth valve 19 are closed. The interfaces allow the filtrate in the lower deep treatment zone 102 to circulate and stir, further improving the uniformity of the reaction. Through the innovative combination of 15+ valves from the First Four-Way system, the three functions of liquid addition, reuse, and circulation are achieved.

[0029] In a preferred embodiment, a second four-way valve 20 is connected to the circulation pipe 11, and the waste liquid discharge pipe 9 is connected to the circulation pipe 11 through the second four-way valve 20. A seventh valve 21 and an eighth valve 22 are respectively provided at the two horizontal interfaces of the second four-way valve 20. The vertical direct port at one end of the second four-way valve 20 is connected to the vertical direct port at one end of the first four-way valve 15. A ninth valve 23 is provided at the vertical direct port at the other end of the second four-way valve 20. A second delivery pump 24 is connected to the waste liquid discharge pipe 9. When the waste liquid in the upper pretreatment zone 101 is discharged, the seventh valve 21, the eighth valve 22, and the second transfer pump 24 are opened, and the sixth valve 19 and the ninth valve 23 are closed. When the filtrate after reaction in the lower deep treatment zone 102 is transported to the upper pretreatment zone 101 for pretreatment, the seventh valve 21 and the eighth valve 22 are closed, and the ninth valve 23 is opened. During the pretreatment reaction in the upper pretreatment zone 101, the seventh valve 21, the ninth valve 23, and the second transfer pump 24 are opened, and the sixth valve 19 and the eighth valve 22 are closed. The interface allows the filtrate in the upper pretreatment zone 101 to circulate and stir, further improving the reaction uniformity.

[0030] In a preferred embodiment, a first online pH meter 25 and a second online pH meter 26 are respectively provided on the circulation pipe 11. The first online pH meter 25 and the second online pH meter 26 can detect the pH value of the acid or alkali solution inside the circulation pipe 11. When the lower deep treatment zone 102 is undergoing deep reaction, the filtrate of the lower deep treatment zone 102 is circulated and stirred. The acidity or alkalinity during the reaction is detected in real time by the first online pH meter 25. When the acidity or alkalinity is insufficient, the third valve 16 and the fourth valve 17 are opened to supplement fresh acid or alkali solution. When the upper pretreatment zone 101 is undergoing pretreatment reaction, the filtrate of the upper pretreatment zone 101 is circulated and stirred. The acidity or alkalinity during the reaction is detected in real time by the second online pH meter 26. When the acidity or alkalinity is insufficient, the fourth valve 17 and the sixth valve 19 are opened to supplement a small amount of fresh acid or alkali solution. This achieves layered circulation stirring (lower layer self-circulation + upper layer filtrate circulation) combined with pH closed-loop control, so that the zone maintains the optimal reaction pH and improves product quality and yield.

[0031] In a specific example, a third transfer pump 27 is connected to the new liquid inlet pipe 10. The third transfer pump 27 is used to add fresh acid or alkali and provide a stable output pressure. The inlet end of the third transfer pump 27 is connected to a new acid pipe 28 and a new alkali pipe 29, respectively. The new acid pipe 28 is connected to an external acid storage tank, and the new alkali pipe 29 is connected to an external alkali storage tank. A tenth valve 30 is provided on the new acid pipe 28, and an eleventh valve 31 is provided on the new alkali pipe 29. The tenth valve 30 and the eleventh valve 31 control the on / off of acid / alkali respectively to prevent acid and alkaline media from mixing in front of the pump and causing a neutralization reaction.

[0032] In a preferred embodiment, a sandwich structure 106 is provided on the side wall of the separation tank 1. Cooling water, heat transfer oil or steam can be introduced into the sandwich structure 106 to achieve temperature rise and fall of the material in the separation tank 1, and ensure that the separation environment temperature in the separation tank 1 meets the reaction requirements.

[0033] The above description, in conjunction with specific / preferred embodiments, provides a further detailed explanation of the present invention and should not be construed as limiting the specific implementation of the present invention to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the protection scope of the present invention. In the description of this specification, the reference to terms such as "an embodiment," "some embodiments," "preferred embodiment," "example," "specific example," or "some examples," etc., indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the described specific features, structures, materials, or characteristics can be combined in a suitable manner in any one or more embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples. Although embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations may be made herein without departing from the scope of protection of the patent application.

Claims

1. A separation device for chitin fiber production, characterized in that: The system includes a separation tank, the interior of which is divided into an upper pretreatment zone and a lower deep treatment zone by a partition plate. A feeding port is located at the top of the separation tank. A first filter screen and a second filter screen are respectively installed in the upper pretreatment zone and the lower deep treatment zone. A rotating shaft is located on the central axis of the separation tank, and stirring paddles corresponding to the upper pretreatment zone and the lower deep treatment zone are respectively installed on the rotating shaft. One end of the rotating shaft is connected to a drive motor. The upper pretreatment zone and the lower deep treatment zone are connected through a first discharge cylinder. A second discharge cylinder is connected to the bottom of the separation tank. A first valve and a second valve are respectively installed at the outlets of the first discharge cylinder and the second discharge cylinder. A waste liquid discharge pipe is connected to the bottom of the upper pretreatment zone, and a fresh liquid inlet pipe is connected to the upper part of the lower deep treatment zone. The lower part of the lower deep treatment zone is connected to the upper part of the upper pretreatment zone through a circulation pipe, and a first delivery pump is installed on the circulation pipe.

2. The separation device for the production of chitin fibers according to claim 1, characterized in that: The bottom of the partition plate and the separation tank are both designed with a conical bottom structure. The first filter screen and the second filter screen are both conical filter screens. A first gap space is provided between the first filter screen and the partition plate. The waste liquid discharge pipe is connected to the first gap space. A second gap space is provided between the second filter screen and the bottom of the separation tank. The lower end of the circulation pipe is connected to the second gap space.

3. The separation device for the production of chitin fibers according to claim 2, characterized in that: The top inlet of the first discharge cylinder is connected to the lowest point of the first filter screen, and the top inlet of the second discharge cylinder is connected to the lowest point of the second filter screen. The shaft is provided with two spiral blades corresponding to the first discharge cylinder and the second discharge cylinder, respectively. The two spiral blades extend from the inside of the first discharge cylinder and the second discharge cylinder to the top of the filter screen.

4. The separation device for the production of chitin fibers according to claim 3, characterized in that: The agitator is an anchor-frame agitator, and the bottom of the anchor frame of the agitator is set as an arc-shaped frame structure corresponding to the conical bottom of the first filter screen or the second filter screen.

5. The separating device for the production of chitin fibers according to any one of claims 1 to 4, characterized in that: The circulation pipe is connected to a first four-way valve, and the new liquid inlet pipe is connected to the circulation pipe through the first four-way valve. The two horizontal interfaces of the first four-way valve are respectively provided with a third valve and a fourth valve, and the two vertical interfaces of the first four-way valve are respectively provided with a fifth valve and a sixth valve.

6. The separation apparatus for chitin fiber production as described in claim 5, characterized in that: The circulation pipe is connected to a second four-way valve, and the waste liquid discharge pipe is connected to the circulation pipe through the second four-way valve. The two horizontal interfaces of the second four-way valve are respectively provided with a seventh valve and an eighth valve. The vertical direct port at one end of the second four-way valve is connected to the vertical direct port at one end of the first four-way valve. A ninth valve is provided at the vertical direct port at the other end of the second four-way valve. The waste liquid discharge pipe is connected to a second delivery pump.

7. The separation device for the production of chitin fibers according to claim 6, characterized in that: The circulation tube is equipped with a first online pH meter and a second online pH meter.

8. The separation device for the production of chitin fibers according to claim 7, characterized in that: The new liquid inlet pipe is connected to a third delivery pump, and the inlet end of the third delivery pump is connected to a new acid pipe and a new alkali pipe respectively. The new acid pipe is equipped with a tenth valve, and the new alkali pipe is equipped with an eleventh valve.

9. The separation device for the production of chitin fibers according to claim 8, characterized in that: The sidewall of the separation tank is designed with a sandwich structure.

10. The separation device for the production of chitin fibers according to claim 9, characterized in that: A hopper is provided at the feeding port.

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