Intermittent methanol rectification device

Abstract

The utility model discloses an intermittent methanol rectification device and belongs to the technical field of machinery. The distillation kettle comprises a main distillation kettle body, a condensing device and a secondary distillation kettle, the main distillation kettle body and the stirring mechanism have a synergistic effect, methanol in a raw material solution is distilled, methanol steam is cooled and liquefied after reaching the condensing device, and finally, the methanol is distilled again through the secondary distillation kettle, so that rectification and purification of the methanol are realized. Impurities with boiling points higher than that of methanol in raw material liquid are separated from the methanol through first constant-temperature distillation; impurities with lower boiling points in the methanol steam are separated through condensation, and finally secondary distillation is performed, so that the purity of a methanol product is greatly improved.

Description

Technical Field

[0001] The utility model belongs to the field of mechanical technology, and in particular relates to an intermittent methanol distillation device. Background Art

[0002] Distillation is a separation process that uses the different volatilities of the components in a mixture to separate them. In the process of chemical production of methanol, a distillation device is needed to purify the methanol. The commonly used distillation device is a distillation tower. The methanol mixture is heated and evaporated in the distillation tower. When the steam contacts the porous partition during the rising process, the vapor has different boiling points, and the mixed gas molecules other than methanol are condensed on the surface of the plate and then drip back. The contact between the reflux liquid and the steam promotes the purification of methanol. Finally, high-purity methanol is obtained above the distillation tower, and turbid liquid is obtained below the distillation tower. This distillation method will produce a large amount of methanol at the bottom of the distillation tower. A large number of bubbles are generated in the process, and the generation of bubbles will affect the steam. The accumulation of steam will not only affect the rise of the steam, but also be mixed in the methanol vapor, affecting the purity of the methanol. Although the setting of the partition can achieve the effect of condensation and separation, the contact between the steam and the condensate is not sufficient. A large number of tiny bubbles will be generated in the general distillation device when distilling methanol. The bubbles hinder the circulation of steam and affect the purity of methanol. The steam is not in complete countercurrent contact with the reflux liquid during the rising process, and the distillation efficiency is low. Therefore, a methanol distillation device is needed to reduce the generation of bubbles and improve the purity of methanol. Utility Model Content

[0003] In view of the above problems existing in the prior art, the technical problem to be solved by the utility model is to provide an intermittent methanol distillation device to solve the problem that steam in the current distillation equipment is prone to aggregation and the purification and separation effect is poor.

[0004] In order to solve the above technical problems, the technical solutions adopted by the utility model are as follows:

[0005] The invention discloses an intermittent methanol distillation device, which is connected in sequence with: a main distillation kettle body, a condensing device and a secondary distillation kettle. A stirring mechanism is arranged in the main distillation kettle body. The main distillation kettle body distills the methanol in the raw material liquid. After the methanol vapor reaches the condensing device, it is cooled and liquefied, and finally distilled again by the secondary distillation kettle to realize the distillation and purification of the methanol.

[0006] Furthermore, the main distillation kettle body is provided with an auxiliary installation device; the auxiliary installation device is symmetrically arranged on the left and right sides of the main distillation kettle body.

[0007] Furthermore, a heating device and a temperature sensor are provided in the main distillation kettle body. The heating device is arranged at the bottom of the main distillation kettle body, and a control switch thereof is arranged outside the bottom of the main distillation kettle body.

[0008] Furthermore, the stirring mechanism comprises: a motor, a stirring shaft, and a stirring auxiliary blade and a stirring main blade arranged on the stirring shaft.

[0009] Furthermore, the motor is arranged on the outside of the top end of the main distillation kettle body; one end of the stirring shaft is arranged on the output shaft of the motor, and the other end extends to the inside of the main distillation kettle body; the stirring main blade is arranged at the end of the stirring shaft extending to the main distillation kettle body; the stirring auxiliary blade is located above the stirring main blade and is arranged on the stirring shaft.

[0010] Furthermore, the main stirring blade is designed to be U-shaped.

[0011] Furthermore, a steam conduit is provided on the right side of the top of the main distillation kettle body, and the other side of the steam conduit is connected to a temporary storage bin; the condensing device is arranged above the temporary storage bin through the conduit, and an air outlet is provided at the upper end of the condensing device.

[0012] Furthermore, a secondary distillation kettle is provided below the temporary storage bin via a conduit, and a valve a is provided between the temporary storage bin and the secondary distillation kettle.

[0013] Furthermore, a conduit is provided at the upper end of the secondary distillation kettle, and a valve b is provided on the conduit.

[0014] Furthermore, the secondary distillation kettle further distills the purified methanol, and the purified methanol vapor is collected from the collecting port at the end of the conduit located above the secondary distillation kettle, thereby achieving the distillation and purification of methanol.

[0015] Compared with the prior art, the utility model has the following advantages:

[0016] (1) The utility model adopts two distillation kettles connected in series to carry out the distillation and purification of methanol. A temporary storage bin is cleverly arranged between the two distillation kettles, which can not only play a certain buffering role on the methanol vapor gas flow, but also collect the condensed and liquefied liquid methanol.

[0017] (2) The utility model separates the impurities with a higher boiling point than methanol from the raw material liquid through the first constant temperature distillation; separates the impurities with a lower boiling point from the methanol vapor through condensation, and finally performs a second distillation, thereby greatly improving the purity of the methanol product.

[0018] (3) The utility model adopts the method of stirring first and then heating during the first distillation, which can make the raw material liquid heated evenly, which is beneficial to the evaporation of methanol and helps to reduce the generation of bubbles. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0020] The accompanying drawings are marked as follows: 1. electric motor; 2. feed inlet; 3. stirring shaft; 4. auxiliary stirring blade; 5. main distillation kettle body; 6. discharge port; 7. heating device; 8. steam duct; 9. temperature sensor; 10. auxiliary installation device; 11. main stirring blade; 12. fixed support foot; 13. air outlet; 14. condensing device; 15. temporary storage bin; 16. valve a; 17. valve b; 18. secondary distillation kettle; 19. collecting port. DETAILED DESCRIPTION

[0021] The utility model is further described below in conjunction with the accompanying drawings.

[0022] A batch methanol distillation device, such as Figure 1 As shown, it includes a main distillation kettle body 5, an electric stirring mechanism, a temporary storage bin 15, a condensing device 14 and a secondary distillation kettle 18; wherein, the main distillation kettle body 5 includes a feed inlet 2, an auxiliary installation device 10, a temperature sensor 9, a discharge port 6, a heating device 7 and a fixed support leg 12; the electric stirring mechanism includes: a motor 1, a stirring shaft 3, a stirring auxiliary blade 4 and a stirring main blade 11; the upper end of the main distillation kettle body 5 is connected to the temporary storage bin 15 through a steam conduit 8, a condensing device 14 is arranged above the temporary storage bin 15, and a secondary distillation kettle 18 is arranged below the temporary storage bin 15.

[0023] The main distillation kettle body 5 is provided with an openable feed port 2 at the upper end, and the methanol raw material enters the main distillation kettle body 5 through the feed port 2; the auxiliary installation device 10 is symmetrically arranged on the left and right sides of the main distillation kettle body 5, respectively, to assist in fixing the distillation kettle body 5, and to prevent the distillation kettle body 5 from shaking due to the stirring of the electric stirring mechanism when distilling the methanol raw material; the temperature sensor 9 is arranged on one side inside the main distillation kettle body 5, with the lower end extending below the liquid level line and the upper end extending to the top of the distillation kettle body 5, which can sensitively sense the temperature change of the methanol raw material liquid inside the main distillation kettle body 5, and can timely convert the temperature into a usable output signal, which is convenient for real-time monitoring of the temperature of the methanol raw material liquid inside the main distillation kettle body 5. The openable discharge port 6 is located at the lower left of the main distillation kettle body 5, and is used to discharge the impurity product from the main distillation kettle body 5 after the distillation is completed; the heating device 7 is arranged at the bottom of the main distillation kettle body 5, and its switch is arranged on the outside of the bottom of the main distillation kettle body 5, which can set a specific heating temperature and provide a heat source to distill the methanol raw material liquid inside the main distillation kettle body 5. The fixed legs 12 are arranged on the outer side of the bottom of the main distillation kettle body 5 and mainly play a supporting role.

[0024] The electric stirring mechanism is provided with a motor 1, a stirring shaft 3, a stirring auxiliary blade 4 and a stirring main blade 11 in sequence from top to bottom; wherein the motor 1 is arranged on the outer side of the top end of the main distillation kettle body 5, mainly providing power to drive the stirring shaft 3 below to rotate, and then stirring the methanol raw material liquid inside the main distillation kettle body 5, so that it can be heated evenly during distillation, and the evaporation of methanol is accelerated; the top end of the stirring shaft 3 is arranged on the output shaft of the motor 1, extending to the inside of the main distillation kettle body 5, and is mainly used for transmitting power; the stirring main blade 11 is arranged at the end of the stirring shaft 3, and is mainly used for stirring the methanol The stirring blade 4 is located above the stirring main blade 11 and is arranged on the stirring shaft 3. When too much raw liquid is added to the main distillation kettle body 5 at one time, the liquid level exceeds the stirring blade 4. At this time, the stirring efficiency of the stirring main blade 11 will be reduced. In order to avoid uneven heating due to insufficient stirring during distillation, which affects the evaporation efficiency of methanol, an additional stirring blade 4 is provided to share part of the resistance of the stirring main blade 11.

[0025] A steam duct 8 is arranged on the right side of the top of the main distillation kettle body 5, and a temporary storage bin 15 is connected to the other side of the steam duct 8. The temporary storage bin 15 is mainly used for temporarily storing the liquid methanol that is evaporated from the main distillation kettle body 5 and is transported through the steam duct 8 to the condensation device 14 for condensation and reflux; a condensation device 14 is arranged above the temporary storage bin 15, and an air outlet 13 is arranged at the upper end of the condensation device 14. When the methanol evaporated from the main distillation kettle body 5 is transported through the steam duct 8 to the condensation device 14, the hot vapor of the methanol is rapidly cooled down and liquefied into methanol, while the impurity components with a boiling point lower than that of methanol will continue to pass upward through the air outlet 13 and be discharged from the device. A secondary distillation kettle 18 is provided below the temporary storage bin 15. The methanol liquid temporarily stored in the temporary storage bin 15 can be introduced into the secondary distillation kettle 18 by opening and closing the valve a 16 provided between the temporary storage bin 15 and the secondary distillation kettle 18; in the secondary distillation kettle 18, the distillation temperature is controlled to be the boiling point of methanol, so that the purified methanol is further distilled, and the purified methanol vapor is collected from the collecting port 19 at the end of the conduit located above the secondary distillation kettle 18, thereby realizing the distillation and purification of methanol.

[0026] The working principle of the utility model is as follows: open the feed port 2, close the discharge port 6, pour the methanol raw material liquid from the feed port 2 into the main distillation kettle body 5 until the liquid surface covers the stirring auxiliary blade 4, close the feed port 2, and start the motor 1. Under the action of the motor 1, the stirring shaft 3 will drive the stirring main blade 11 and the stirring auxiliary blade 4 to rotate at the same angular velocity, thereby driving the methanol raw material liquid in the main distillation kettle body 5 to stir. At this time, the heating device 7 is started and the heating temperature is set to 65°C. (Since the boiling point of methanol is around 64.5°C, setting the heating temperature to 65°C can ensure that all the methanol in the raw material liquid can reach the boiling point and be evaporated and separated; it can also prevent impurities in the methanol raw material liquid with a boiling point higher than that of methanol from being evaporated and mixed into the methanol vapor); since the temperature sensor 9 is arranged on one side inside the main distillation kettle body 5, with the lower end extending below the liquid level line and the upper end extending to the top of the distillation kettle body 5, it can sensitively sense the temperature changes of the methanol raw material liquid inside the main distillation kettle body 5, and can timely convert the temperature into a usable output signal, which is convenient for real-time monitoring of the temperature of the methanol raw material liquid inside the main distillation kettle body 5, and further ensures that the temperature of the raw material liquid inside the distillation kettle body 5 is maintained at 65°C. After the heating of the heating device 7 and the stirring of the stirring mechanism, the methanol raw liquid in the distillation kettle body 5 can be evenly heated, and the methanol vapor will flow into the temporary storage bin 15 from the steam conduit 8. At this time, the valve a 16 is closed. After the methanol vapor is buffered in the temporary storage bin 15, it will pass through the condensing device 14. The methanol vapor is quickly cooled and liquefied into liquid methanol through condensation. Under the action of gravity, the liquid methanol will drip into the temporary storage bin 15 along the inner tube wall. When it converges to a certain extent (that is, to ensure that the liquid level does not exceed the steam conduit to prevent methanol from flowing back into the distillation kettle body 5), the valve a 16 is opened to introduce the liquid methanol into the secondary distillation kettle 18. The impurities in the methanol vapor with a boiling point much lower than that of methanol cannot be liquefied due to the cooling of the condensing device 14, and will flow out of the device from the gas outlet 13 along with the air flow. Therefore, the impurities with higher and lower boiling points in the methanol entering the secondary distillation kettle 18 from the temporary storage bin 15 are well removed.

[0027] In order to achieve further purification, the methanol arriving in the secondary distillation kettle 18 can be distilled and purified again in the secondary distillation kettle 18. When the temperature of the methanol in the secondary distillation kettle 18 reaches the boiling point, the valve b 17 is opened to discharge the further purified methanol vapor to the collecting port 19 for collection. At this time, the purity of the methanol can be further improved.

[0028] As more and more methanol is separated and purified from the raw liquid, the methanol content in the raw liquid becomes lower and lower, until finally, the components in the raw liquid contain almost no methanol. At this time, the discharge port 6 is opened, and the impurities will be discharged from the device together with the raw liquid from the discharge port 6; at this time, the new methanol raw material can be distilled and purified by methanol.

[0029] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An intermittent methanol distillation device, which is sequentially connected with: a main distillation kettle body (5), a condensing device (14) and a secondary distillation kettle (18), characterized in that: A stirring mechanism is provided in the main distillation kettle body (5), and the main distillation kettle body (5) distills the methanol in the raw material liquid. After the methanol vapor reaches the condensing device (14), it is cooled and liquefied, and finally distilled again by the secondary distillation kettle (18) to achieve the distillation and purification of methanol.

2. The intermittent methanol distillation device according to claim 1, characterized in that: The main distillation kettle body (5) is provided with an auxiliary installation device (10); the auxiliary installation device (10) is symmetrically arranged on the left and right sides of the main distillation kettle body (5).

3. The intermittent methanol distillation device according to claim 1, characterized in that: The main still body (5) is provided with a heating device (7) and a temperature sensor (9). The heating device (7) is arranged at the bottom of the main still body (5), and its control switch is arranged outside the bottom of the main still body (5).

4. The intermittent methanol distillation device according to claim 1, characterized in that: The stirring mechanism comprises: a motor (1), a stirring shaft (3), and a stirring auxiliary blade (4) and a stirring main blade (11) arranged on the stirring shaft (3).

5. The intermittent methanol distillation device according to claim 4, characterized in that: The motor (1) is arranged on the outside of the top end of the main distillation kettle body (5); one end of the stirring shaft (3) is arranged on the output shaft of the motor (1), and the other end extends to the inside of the main distillation kettle body (5); the stirring main blade (11) is arranged at the end of the stirring shaft (3) extending to the main distillation kettle body (5); the stirring auxiliary blade (4) is located above the stirring main blade (11) and is arranged on the stirring shaft (3).

6. The intermittent methanol distillation device according to claim 5, characterized in that: The main stirring blade (11) is designed to be U-shaped.

7. The intermittent methanol distillation device according to claim 1, characterized in that: A steam conduit (8) is provided on the right side of the top of the main distillation kettle body (5), and the other side of the steam conduit (8) is connected to a temporary storage bin (15); the condensing device (14) is provided above the temporary storage bin (15) through a conduit, and an air outlet (13) is provided at the upper end of the condensing device (14).

8. The intermittent methanol distillation device according to claim 7, characterized in that: A secondary distillation kettle (18) is provided below the temporary storage bin (15) via a conduit, and a valve a (16) is provided between the temporary storage bin (15) and the secondary distillation kettle (18).

9. The intermittent methanol distillation device according to claim 1, characterized in that: The upper end of the secondary distillation kettle (18) is provided with a conduit, and the conduit is provided with a valve b (17).

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