Vinylene carbonate short-path molecular distillation device

Abstract

The utility model discloses a short-path molecular distillation device for vinylene carbonate. The short-path molecular distillation device comprises a molecular distiller, a heavy-phase circulating tank, a heavy-phase tank, a light-phase tank and a pipeline, a heavy phase outlet in the lower part of the molecular distiller is connected with a top feeding hole of the heavy phase circulating tank through a pipeline and is connected with a top feeding hole of the heavy phase tank through a pipeline, and the pipeline is connected with a heavy phase circulating tank valve; a light phase outlet in the bottom of the molecular distiller is connected with a feeding hole in the top of the light phase tank through a pipeline. Compared with the traditional distillation technology, the short-path molecular distillation device disclosed by the utility model is higher in separation purity, low in material loss rate, high in yield, good in mass transfer, low in energy consumption and low in safety risk, and is designed according to the average free path of each component of vinylene carbonate.

Description

Technical Field

[0001] The utility model relates to the technical field of distillation separation and purification of vinylene carbonate, and particularly relates to a short-path molecular distillation device for vinylene carbonate. Background Art

[0002] In the new energy lithium battery additive industry, vinylene carbonate, as a film-forming additive with mature application and stable characteristics, can assist lithium batteries to achieve a large performance improvement. It is the electrolyte additive with the largest consumption. The distillation separation and purification technology in its production process plays a very important role in the finished product quality of vinylene carbonate.

[0003] Although conventional distillation devices are widely used, for the separation and treatment of some complex mixtures, the distillation effect is not ideal, and there are problems such as high energy consumption and low separation efficiency. The short-path molecular distillation device adopted by the utility model can solve the problems that cannot be solved by traditional distillation devices, with higher separation purity, low material loss rate and high yield. It is designed according to the average free path of each component of vinylene carbonate, with good mass transfer, low energy consumption and low safety risk. Summary of the Utility Model

[0004] Based on the above description, the utility model provides a short-path molecular distillation device for vinylene carbonate to solve the problems of unsatisfactory distillation effect, high energy consumption and low separation efficiency of traditional distillation devices.

[0005] The technical solution of the utility model to solve the above technical problems is as follows:

[0006] A short-path molecular distillation device for vinylene carbonate, comprising a molecular distiller, a heavy-phase circulation tank, a heavy-phase tank, a light-phase tank and pipelines;

[0007] The lower heavy-phase outlet of the molecular distiller is connected to the top feed inlet of the heavy-phase circulation tank through a pipeline and is connected to the top feed inlet of the heavy-phase tank through a pipeline;

[0008] The light-phase outlet at the bottom of the molecular distiller is connected to the top feed inlet of the light-phase tank through a pipeline;

[0009] The discharge outlet at the bottom of the heavy-phase circulation tank is connected to the feed inlet of the molecular distiller through a pipeline.

[0010] Based on the above technical solution, the utility model can also be improved as follows:

[0011] Further, a heavy-phase circulation tank valve is connected to the pipeline between the heavy-phase outlet and the top feed inlet of the heavy-phase circulation tank, a heavy-phase tank valve is connected to the pipeline between the heavy-phase outlet and the top feed inlet of the heavy-phase tank, and a light-phase tank valve is connected to the pipeline between the light-phase outlet and the top feed inlet of the light-phase tank.

[0012] Furthermore, it further includes a feed liquid tank. A molecular distiller feed inlet is provided at the top of the molecular distiller. A feed valve is connected to the pipeline between the feed liquid tank and the molecular distiller feed inlet.

[0013] Furthermore, it further includes a feeding pump, which is connected between the feed valve and the molecular distiller feed inlet.

[0014] Furthermore, it further includes a heavy phase tank extraction pump, and the discharge port at the bottom of the heavy phase tank is connected to the heavy phase tank extraction pump.

[0015] Furthermore, it further includes a light phase extraction pump, and the discharge port at the bottom of the light phase tank is connected to the light phase extraction pump.

[0016] Furthermore, the molecular distiller includes a housing, a heating device, a heat medium pipe, a condensing pipe, a liquid separation tray and a molecular distiller scraper. The liquid separation tray and the molecular distiller scraper are connected inside the molecular distiller and are driven by a driving member to rotate.

[0017] Furthermore, the discharge port at the bottom of the heavy phase circulation tank is connected to the molecular distiller feed inlet through a heavy phase circulation tank outlet valve via a feeding pump. The discharge of the heavy phase circulation tank is extracted by the feeding pump and circulated into the molecular distiller.

[0018] Furthermore, a refrigerant inlet and a refrigerant outlet connected to the internal condensing pipe are provided on the housing of the molecular distiller. A heat medium inlet and a heat medium outlet connected to the internal heat medium pipe are provided on the housing. The refrigerant inlet, the refrigerant outlet, the heat medium inlet and the heat medium outlet are respectively controlled by a refrigerant inlet valve, a refrigerant outlet valve, a heat medium inlet valve and a heat medium outlet valve.

[0019] Furthermore, the heavy phase tank, the light phase tank and the heavy phase circulation tank are connected to an external nitrogen source through a heavy phase tank interlock nitrogen switch valve, a light phase tank interlock nitrogen switch valve and a heavy phase circulation tank interlock nitrogen switch valve.

[0020] Furthermore, the tail gas outlets of the molecular distiller, the heavy phase circulation tank, the heavy phase tank and the light phase tank are all connected to a tail gas treatment device through pipelines.

[0021] Compared with the prior art, the technical solution of the present utility model has the following beneficial technical effects:

[0022] ① Improve production safety: Short-path molecular distillation is free evaporation on the surface of the liquid layer, carried out under low pressure, and separated according to the different molecular mean free paths. Therefore, the distillation temperature is much lower than the boiling point of the raw material. During the production process, it is safer and more controllable than traditional distillation that relies on azeotropy to achieve the separation effect.

[0023] ②Good mass transfer and low energy consumption: Since there is less overheating loss in the whole separation process of molecular distillation, and due to the structural form of the molecular distillation device, the internal pressure is extremely low, the internal resistance is much smaller than that of conventional distillation, and the heating and cooling rates are faster than those of traditional distillation. There is no need for long-term preheating and cooling, so energy consumption can be greatly saved.

[0024] ③Improve production efficiency: Compared with traditional distillation, short-path molecular distillation can heat up and cool down quickly, with a faster speed. Due to the very short distillation path, the mixture is exposed for a very short time in short-path molecular distillation, with fewer side reactions, and it can save time more effectively and ensure better separation efficiency.

[0025] ④Ensure stable product quality: Compared with traditional distillation, short-path molecular distillation has a higher separation degree. Molecular distillation can separate substances that are difficult to separate conventionally, and the separated products are non-toxic, harmless, pollution-free, and residue-free, and pure and safe products can be obtained, with stable product quality.

[0026] ⑤The short-path molecular distillation device of the present utility model has a higher separation purity, lower material loss rate, and higher yield compared with traditional distillation technology. It is designed according to the average free path of each component of vinylene carbonate, with good mass transfer, low energy consumption, and low safety risk. Description of the Drawings

[0027] Figure 1 It is a schematic diagram of the overall structure of a short-path molecular distillation device for vinylene carbonate provided by an embodiment of the present utility model.

[0028] Figure 2 It is a schematic diagram of the overall structure of a molecular distiller provided by an embodiment of the present utility model.

[0029] In the drawings, the components represented by each reference numeral are as follows:

[0030] 1. Molecular distiller; 101. Shell, 102. Motor, 103. Feed inlet of the molecular distiller, 104. Light-phase outlet, 105. Heavy-phase outlet, 106. Vacuum-phase outlet, 107. Refrigerant inlet, 108. Refrigerant outlet, 109. Heat medium inlet, 110. Heat medium outlet; 2. Heavy-phase circulation tank; 3. Heavy-phase tank; 4. Light-phase tank; 5. Refrigerant inlet valve; 6. Refrigerant outlet valve; 7. Heat medium inlet valve; 8. Heat medium outlet valve; 9. Feeding pump; 10. Scraper of the molecular distiller; 11. Outlet valve of the heavy-phase circulation tank; 12. Valve of the heavy-phase circulation tank; 13. Valve of the heavy-phase tank; 14. Extraction pump of the heavy-phase tank; 15. Extraction pump of the light phase; 16. Valve of the light-phase tank; 17. Feed valve; 18. Tail gas; 19. Interlock nitrogen switch valve of the heavy-phase tank; 20. Interlock nitrogen switch valve of the light-phase tank; 21. Condensing pipe; 22. Interlock nitrogen switch valve of the heavy-phase circulation tank; 23. Nitrogen source. Detailed Embodiments

[0031] To facilitate the understanding of this application, the following will provide a more comprehensive description of this application with reference to the relevant accompanying drawings. Embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of this application more thorough and comprehensive.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0033] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediate element. In the following embodiments, "connection", if there is an electrical signal or data transfer between the connected circuits, modules, units, etc., should be understood as "electrical connection", "communication connection", etc.

[0034] It should also be understood that terms such as "include / comprise" or "have" etc. specify the existence of the stated features, wholes, steps, operations, components, parts or combinations thereof, but do not exclude the possibility of the existence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof.

[0035] In the liquid-liquid separation technology, distillation (rectification) is one of the most common and widely used technologies. What we commonly see includes ordinary rectification, extractive rectification, azeotropic rectification, heat pump rectification, reactive rectification, etc. Most of them rely on the boiling point difference, while short-path molecular distillation relies on the molecular mean free path. According to the fact that the light components have a long free path and the heavy components have a short free path, the purpose of separation and purification is achieved under the combined action of the condenser and the heating device. This process can also be used in the production of vinylene carbonate and has significant advantages in terms of safety, energy conservation, production efficiency, product quality, etc.

[0036] The present utility model provides a short-path molecular distillation device for vinylene carbonate, comprising a molecular distiller 1, a heavy-phase circulation tank 2, a heavy-phase tank 3, a light-phase tank 4, and pipelines;

[0037] The lower heavy-phase outlet 105 of the molecular distiller 1 is connected to the top feed port of the heavy-phase circulation tank 2 through a pipeline and is connected to the top feed port of the heavy-phase tank 3 through a pipeline;

[0038] The light-phase outlet 104 at the bottom of the molecular distiller 1 is connected to the top feed port of the light-phase tank 4 through a pipeline;

[0039] The discharge port at the bottom of the heavy-phase circulation tank 2 is connected to the feed port 103 of the molecular distiller through a pipeline.

[0040] In this embodiment, a heavy-phase circulation tank valve 12 is connected to the pipeline between the heavy-phase outlet 105 and the top feed port of the heavy-phase circulation tank 2, a heavy-phase tank valve 13 is connected to the pipeline between the heavy-phase outlet 105 and the top feed port of the heavy-phase tank 3, and a light-phase tank valve 16 is connected to the pipeline between the light-phase outlet 104 and the top feed port of the light-phase tank 4.

[0041] In this embodiment, the tail gas outlets of the molecular distiller 1, the heavy-phase circulation tank 2, the heavy-phase tank 3, and the light-phase tank 4 are all connected to the tail gas treatment device through pipelines.

[0042] In this embodiment, a feed liquid tank is further included. The molecular distiller 1 is provided with a molecular distiller feed port 103 at the top, and a feed valve 17 is connected to the pipeline between the feed liquid tank and the molecular distiller feed port 103.

[0043] In this embodiment, the above-mentioned short-path molecular distillation device for vinylene carbonate further includes a feeding pump 9, and the feeding pump 9 is connected between the feed valve 17 and the molecular distiller feed port 103.

[0044] In this embodiment, the above-mentioned short-path molecular distillation device for vinylene carbonate further includes a heavy-phase tank extraction pump 14, and the discharge port at the bottom of the heavy-phase tank is connected to the heavy-phase tank extraction pump 14.

[0045] Furthermore, the above-mentioned short-path molecular distillation device for vinylene carbonate further includes a light-phase extraction pump 15, and the discharge port at the bottom of the light-phase tank is connected to the light-phase extraction pump 15.

[0046] Specifically, the molecular distiller 1 includes a housing 101, a heating device, a heat medium pipe, a condensing pipe 21, a liquid separation tray, and a molecular distiller scraper 10. The liquid separation tray and the molecular distiller scraper 10 are connected inside the molecular distiller 1 and are driven to rotate by a driving member.

[0047] Specifically, after the heat medium enters the heat medium pipe inside the housing from the heat medium inlet 109, it flows out from the heat medium outlet 110; the refrigerant enters the condensing pipe inside the housing from the refrigerant inlet 107 and flows out from the refrigerant outlet 108.

[0048] More specifically, the refrigerant is water, and the water temperature at the refrigerant inlet 107 is 7°C; the heat medium is water, and the water temperature at the heat medium inlet 109 is 75°C.

[0049] Furthermore, the driving member can be a motor 102; the motor 102 is connected to the middle of the outer wall of the top surface of the molecular distiller 1, and its output shaft passes through the top wall of the molecular distiller 1 and is connected to the liquid distribution tray and the middle of the molecular distiller scraper 10. The molecular distiller scraper 10 is coaxial with the molecular distiller 1, and both ends are close to both sides of the inner wall of the molecular distiller 1, that is, the width of the molecular distiller scraper 10 is close to the inner diameter of the molecular distiller 1. The material enters the liquid distribution tray, the motor 102 drives the liquid distribution tray to rotate, the liquid material is thrown onto the inner wall surface of the shell, and the molecular distiller scraper 10 rotates to evenly distribute the liquid material along the inner side wall surface of the molecular distiller 1 into a liquid film with a certain thickness.

[0050] In this embodiment, the heating device is arranged outside the shell and can be a heating wire or a heating jacket. The heating device outside the shell 101 enables the separation of light and heavy components of the material. After that, the light components are condensed into a liquid by the built-in condenser tube 21 and then flow downward along the condenser tube 21 and are discharged from the light phase outlet 104, and the heavy components flow downward along the inner side wall surface of the shell 101 and are discharged from the heavy phase outlet 105.

[0051] In this embodiment, a vacuum phase outlet 106 is provided on the shell, and the vacuum phase outlet 106 is connected to a vacuum pump through a pipeline to provide a vacuum environment for the molecular distiller. One or more vacuum pumps can be selected according to the requirements for the degree of vacuum.

[0052] In this embodiment, the discharge port at the bottom of the heavy phase circulation tank 2 is connected to the molecular distiller feed port 103 through the heavy phase circulation tank outlet valve 11 and the feeding pump 9. The discharge of the heavy phase circulation tank 2 is extracted by the feeding pump 9 and circulated into the molecular distiller 1.

[0053] Furthermore, a refrigerant water inlet 107 and a refrigerant water outlet 108 connected to the internal condenser tube are provided on the shell of the molecular distiller 1, and a heat medium water inlet 109 and a heat medium water outlet 110 connected to the internal heat medium tube are provided on the shell. The refrigerant water inlet 107, the refrigerant water outlet 108, the heat medium water inlet 109, and the heat medium water outlet 110 are respectively controlled by a refrigerant inlet valve 5, a refrigerant outlet valve 6, a heat medium inlet valve 7, and a heat medium outlet valve 8.

[0054] Furthermore, the heavy phase tank 3, the light phase tank 4, and the heavy phase circulation tank 2 are connected to an external nitrogen source 23 through a heavy phase tank interlock nitrogen switch valve 19, a light phase tank interlock nitrogen switch valve 20, and a heavy phase circulation tank interlock nitrogen switch valve 22, and this nitrogen is used for nitrogen sealing.

[0055] As shown in the figure, the main process of a short-path molecular distillation device for vinylene carbonate is as follows:

[0056] Open the refrigerant inlet valve 5 and the refrigerant outlet valve 6 of the molecular distiller 1. When the flow rate is reduced to a fixed value by adjusting the valve, open the heat medium inlet valve 7 and the heat medium outlet valve 8 of the molecular distiller 1, start the feeding pump 9, open the feed valve 17, control the feed flow rate, start the scraper 10 of the molecular distiller, open the heavy phase circulation tank valve 12 from the molecular distiller 1 to the heavy phase circulation tank 2 and the light phase tank valve 16 to the light phase tank 4. After the feeding is completed, close the feed valve 17, open the heavy phase circulation tank outlet valve 11, and open the heavy phase tank valve 13. When the material in the heavy phase circulation tank is processed, close the heat medium inlet valve 7 and the heat medium outlet valve 8 of the molecular distiller 1, and stop the scraper 10 of the molecular distiller. During the distillation process, the tail gas 18 is condensed by the distillation cold trap and then pumped to the tail gas treatment device by the vacuum unit. After the distillation process is completed, close the inlet and outlet valves of the vacuum pump and the tail gas pipeline. After the pressure reaches a fixed value, the heavy phase tank interlock nitrogen switch valve 19 and the light phase tank interlock nitrogen switch valve 20 are closed. Start the heavy phase tank extraction pump 14 and the light phase extraction pump 15 according to the regulations. The liquid extracted by the heavy phase tank extraction pump 14 is filled into barrels and sent for waste liquid incineration treatment. The light phase extraction pump 15 transports the light phase to the subsequent process, the rectification raw material temporary storage tank.

[0057] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A vinylene carbonate short-range molecular distillation device, characterized in that: It comprises a molecular distiller (1), a heavy phase circulation tank (2), a heavy phase tank (3), a light phase tank (4), and a pipeline; The lower heavy phase outlet (105) of the molecular distiller (1) is connected to the top feed port of the heavy phase circulation tank (2) through a pipeline, and is connected to the top feed port of the heavy phase tank (3) through a pipeline; The light phase outlet (104) at the bottom of the molecular distiller (1) is connected to the top feed port of the light phase tank (4) through a pipeline; The discharge port at the bottom of the heavy phase circulation tank (2) is connected to the feed port (103) of the molecular distiller via a pipeline.

2. A vinylene carbonate short-range molecular distillation device according to claim 1, characterized in that: A heavy phase circulation tank valve (12) is connected to the pipeline between the heavy phase outlet (105) and the top feed port of the heavy phase circulation tank (2), a heavy phase tank valve (13) is connected to the pipeline between the heavy phase outlet (105) and the top feed port of the heavy phase tank (3), and a light phase tank valve (16) is connected to the pipeline between the light phase outlet (104) and the top feed port of the light phase tank (4).

3. A vinylene carbonate short-range molecular distillation device according to claim 1, characterized in that: It also comprises a liquid feed tank, the top of the molecular distiller (1) is provided with a molecular distiller feed port (103), and a feed valve (17) is connected to the pipeline between the liquid feed tank and the molecular distiller feed port (103).

4. A vinylene carbonate short-range molecular distillation device according to claim 3, characterized in that: The invention also comprises a feeding pump (9), wherein the feeding pump (9) is connected between the feeding valve (17) and the feeding port (103) of the molecular distiller.

5. A vinylene carbonate short-path molecular distillation device according to claim 1, characterized in that: It also comprises a heavy phase tank extraction pump (14), and the discharge port at the bottom of the heavy phase tank is connected to the heavy phase tank extraction pump (14).

6. A vinylene carbonate short-path molecular distillation device according to claim 1, characterized in that: It also comprises a light phase extraction pump (15), and the discharge port at the bottom of the light phase tank is connected to the light phase extraction pump (15).

7. A vinylene carbonate short-range molecular distillation device according to claim 1, characterized in that: The molecular distiller (1) comprises a shell (101), a heating device, a heat medium pipe, a condenser (21), a liquid separation plate and a molecular distiller scraper (10); the liquid separation plate and the molecular distiller scraper (10) are connected inside the molecular distiller (1) and are driven to rotate by a driving member.

8. A vinylene carbonate short-range molecular distillation device according to claim 4, characterized in that: The discharge port at the bottom of the heavy phase circulation tank (2) is connected to the feed port (103) of the molecular distiller via a heavy phase circulation tank outlet valve (11) and a feed pump (9).

9. A vinylene carbonate short-range molecular distillation device according to claim 7, characterized in that: The shell of the molecular distiller (1) is provided with a refrigerant water inlet (107) and a refrigerant water outlet (108) connected to an internal condenser pipe, and the shell is provided with a heat medium water inlet (109) and a heat medium water outlet (110) connected to an internal heat medium pipe. The refrigerant water inlet (107), the refrigerant water outlet (108), the heat medium water inlet (109), and the heat medium water outlet (110) are controlled by a refrigerant inlet valve (5), a refrigerant outlet valve (6), a heat medium inlet valve (7), and a heat medium outlet valve (8), respectively.

10. A vinylene carbonate short-path molecular distillation device according to claim 1, characterized in that: The tail gas outlets of the molecular distiller (1), the heavy phase circulation tank (2), the heavy phase tank (3), and the light phase tank (4) are all connected to the tail gas treatment device through pipelines, and the heavy phase tank (3), the light phase tank (4), and the heavy phase circulation tank (2) are connected to an external nitrogen source (23) through a heavy phase tank interlocking nitrogen switch valve (19), a light phase tank interlocking nitrogen switch valve (20), and a heavy phase circulation tank interlocking nitrogen switch valve (22).

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