Distillation device for chiral propylene glycol

Abstract

The utility model discloses a distillation device for chiral propylene glycol, which is characterized in that after a jacket is matched with a distillation kettle, an accommodating space is formed between the jacket and the distillation kettle, and a steam input unit and a steam reflux unit are respectively connected with the jacket; a material input port, a first output port and a second output port are formed in the upper part of the distillation kettle, the first output port is connected with the input end of the condenser, and the output end of the condenser is connected with the propylene glycol receiving tank; the vacuum pumping unit enables chiral propylene glycol to be input into the distillation still and enables the distillation still to be subjected to reduced pressure distillation, one end of the first valve is connected with the chiral propylene glycol storage unit, the other end of the first valve is connected with the material input port, one end of the second valve is connected with the second output port, and the other end of the second valve is connected with the vacuum pumping unit. And the other end of the second valve is connected with the vacuumizing unit. According to the utility model, the vacuumizing unit is shared in the feeding stage and the distillation stage, and a feeding pump does not need to be independently adopted for feeding, so that the structure is simplified, and the cost is also reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of distillation devices, in particular to a distillation device for chiral propylene glycol. Background Art

[0002] Propylene oxide reacts with water, and the reaction product is distilled in a distillation apparatus to obtain propylene glycol.

[0003] At present, there is a dipropylene glycol distillation and separation device, which has the following structure: it includes a primary tank, a distillation tower, a condenser, a vacuum system, a first intermediate tank, a second intermediate tank, a third intermediate tank, a first product tank, and a second product tank. The bottom of the distillation tower is connected to the primary tank through a feed pump, the top of the distillation tower is connected to the condenser through a pipeline, the outlet end of the condenser is connected to the first intermediate tank, the second intermediate tank, and the third intermediate tank in three ways, and the bottom of the third intermediate tank is connected to the first product tank and the second product tank through a second discharge pump.

[0004] The above-mentioned distillation separation device belongs to atmospheric distillation, and is not applicable to the separation and purification of high-boiling point substances and compounds that are thermally decomposed, oxidized or polymerized before reaching the boiling point during atmospheric distillation, for example, it is not applicable to the distillation of chiral propylene glycol. Utility Model Content

[0005] The utility model provides a distillation device suitable for chiral propylene glycol.

[0006] The technical solutions to the above technical problems are as follows:

[0007] A chiral propylene glycol distillation device comprises a distillation kettle, a jacket, a steam input unit, a steam reflux unit, a condenser, a propylene glycol receiving tank, and a chiral propylene glycol storage unit. After the jacket is matched with the distillation kettle, a holding space is opened between the jacket and the distillation kettle, and the steam input unit and the steam reflux unit are respectively connected to the jacket;

[0008] The upper part of the distillation kettle is provided with a material input port, a first output port, and a second output port, wherein the first output port is connected to the input end of the condenser, and the output end of the condenser is connected to the propylene glycol receiving tank; the distillation kettle also includes a first valve, a second valve, and a vacuum unit for inputting chiral propylene glycol into the distillation kettle and causing the distillation kettle to form a reduced pressure distillation, wherein one end of the first valve is connected to the chiral propylene glycol storage unit, the other end of the first valve is connected to the material input port, one end of the second valve is connected to the second output port, and the other end of the second valve is connected to the vacuum unit.

[0009] Further, the steam input unit includes a first steam unit, a steam input control valve, a steam output control valve, and a second steam unit, the output end of the first steam unit is connected to one end of the steam input control valve, the other end of the steam input control valve is connected to the input port provided on the jacket, the output port provided on the jacket is connected to one end of the steam output control valve, and the other end of the steam output control valve is connected to the second steam unit.

[0010] Furthermore, it also includes a pipeline flame arrester and a tail gas absorption unit, one end of the pipeline flame arrester is connected to the first output port, and the other end of the pipeline flame arrester is connected to the tail gas absorption unit.

[0011] Furthermore, it also includes a compressed gas supply unit and a third valve. The output end of the compressed gas supply unit is connected to one end of the third valve, and the other end of the third valve is connected to the input port arranged on the jacket.

[0012] Furthermore, it also includes a discharge valve and a centrifuge for recovering the catalyst. The lower part of the distillation kettle is provided with a discharge port, one end of the discharge valve is connected to the discharge port, and the other end of the discharge valve is connected to the centrifuge.

[0013] In the utility model, the vacuum unit allows the chiral propylene glycol to be input into the distillation kettle in the feeding stage, and allows the distillation kettle to form a reduced pressure distillation in the distillation stage. In the feeding stage, the first valve and the second valve are opened and the vacuum unit is in a working state. The negative pressure generated by the vacuum unit allows the chiral propylene glycol in the chiral propylene glycol storage unit to be input into the distillation kettle. In the distillation stage, the first valve is closed and the second valve is opened and the vacuum unit is in a working state. The negative pressure generated by the vacuum unit allows the distillation kettle to enter a reduced pressure distillation. The utility model shares the vacuum unit in the feeding stage and the distillation stage, and does not need to use a feeding pump to feed the material separately, which not only simplifies the structure, but also reduces the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the distillation device of chiral propylene glycol of the utility model.

[0015] Markings in the accompanying drawings:

[0016] Distillation kettle 1, material input port 1a, first output port 1b, second output port 1c, jacket 2, condenser 3, propylene glycol receiving tank 4, chiral propylene glycol storage unit 5, accommodating space 6, first valve 7, second valve 8, vacuum unit 9, steam input control valve 10, steam output control valve 11, pipeline flame arrester 12, gas supply unit 13, third valve 14, discharge valve 15, centrifuge 16, cooling water supply control valve 17, cooling water return control valve 18, first steam unit LS, second steam unit SC, tail gas absorption unit VT, temperature sensor T, pressure sensor P. DETAILED DESCRIPTION

[0017] The utility model is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0018] First of all, it should be explained that the described embodiments are merely embodiments derived from the explanation of the drawings, and are not all embodiments of the present utility model. As for the directional words used, such as "upper end" and "lower end", they are merely further explanations of the drawings, rather than limitations on the present utility model.

[0019] like Figure 1 As shown, the chiral propylene glycol distillation device of the utility model comprises a distillation kettle 1, a jacket 2, a steam input unit, a steam reflux unit, a condenser 3, a propylene glycol receiving tank 4, a chiral propylene glycol storage unit 5, a first valve 7, a second valve 8, and a vacuum unit 9. Each part and the relationship between the parts are described in detail below:

[0020] The upper part of the still 1 is provided with a material input port 1a, a first output port 1b, and a second output port 1c, the lower part of the still 1 is provided with a discharge port 1d, and the still 1 is also provided with a stirrer, the structure of which belongs to the prior art and is not described here. The still 1 is provided with a temperature sensor T and a pressure sensor P, the temperature sensor T detects the temperature of the solution in the still 1, and the pressure sensor P detects the pressure in the still 1.

[0021] After the jacket 2 is matched with the distillation kettle 1, a receiving space 6 is opened between the jacket 2 and the distillation kettle 1, and a steam input unit and a steam reflux unit are respectively connected to the jacket 2. The steam input unit includes a first steam unit LS, a steam input control valve 10, a steam output control valve 11, and a second steam unit SC. The output end of the first steam unit LS is connected to one end of the steam input control valve 10, and the other end of the steam input control valve 10 is connected to the input port provided on the jacket 2, and the output port provided on the jacket 2 is connected to one end of the steam output control valve 11, and the other end of the steam output control valve 11 is connected to the second steam unit SC.

[0022] The first output port 1b is connected to the input end of the condenser 3. The gas generated by the distillation of chiral propylene glycol in the distillation kettle 1 enters the condenser 3. The gas is liquefied by the condenser 3 to form chiral propylene glycol liquid. The output end of the condenser 3 is connected to the propylene glycol receiving tank 4. The chiral propylene glycol liquid in the condenser 3 enters the propylene glycol receiving tank 4.

[0023] One end of the first valve 7 is connected to the chiral propylene glycol storage unit 5 , the other end of the first valve 7 is connected to the material input port 1a , one end of the second valve 8 is connected to the second output port 1c , and the other end of the second valve 8 is connected to the vacuum unit 9 .

[0024] The vacuum unit 9 allows the chiral propylene glycol to be input into the still 1 during the loading stage, and allows the still 1 to undergo reduced-pressure distillation during the distillation stage. During the loading stage, the first valve 7 and the second valve 8 are opened, and the vacuum unit 9 is in operation. The negative pressure generated by the vacuum unit 9 allows the chiral propylene glycol in the chiral propylene glycol storage unit 5 to be input into the still 1. During the distillation stage, the first valve 7 is closed, the second valve 8 is opened, and the vacuum unit 9 is in operation. The negative pressure generated by the vacuum unit 9 allows the still 1 to undergo reduced-pressure distillation.

[0025] The utility model also includes a pipeline flame arrester 12 and a tail gas absorption unit VT. One end of the pipeline flame arrester 12 is connected to the first output port 1b, and the other end of the pipeline flame arrester 12 is connected to the tail gas absorption unit VT. In the feeding and distillation stages, the pipeline flame arrester 12 is in a closed state. When the tail gas in the distillation kettle 1 needs to be vented after the distillation, the first valve 7 and the second valve 8 are opened to open the pipeline flame arrester 12, and the tail gas is absorbed by the tail gas absorption unit VT. The tail gas absorption unit VT belongs to the prior art structure, which will not be described here.

[0026] The utility model further comprises a compressed gas supply unit 13 and a third valve 14. The output end of the compressed gas supply unit 13 is connected to one end of the third valve 14, and the other end of the third valve 14 is connected to an input port provided on the jacket 2. The compressed gas supply unit 13 adopts, for example, an air compressor. After the distillation is completed, the steam input control valve 10 is closed, and the third valve 14 is opened. The compressed gas generated by the compressed gas supply unit 13 enters the accommodation space 6 through the third valve 14, so that the steam in the accommodation space 6 quickly flows back to the second steam unit SC.

[0027] The utility model also includes a cooling water supply control valve 17 and a cooling water return control valve 18. The cooling water supply control valve 17 is connected to the input port provided on the jacket 2, and the cooling water return control valve 18 is connected to the output port provided on the jacket 2. The cooling water supply control valve 17 is connected in parallel with the steam input control valve 10 and the third valve 14, and the cooling water return control valve 18 is connected in parallel with the steam output control valve 11.

[0028] After the steam in the above-mentioned storage space 6 is quickly refluxed into the second steam unit SC by the action of the compressed gas, the steam output control valve 11 is closed, and the cooling water supply control valve 17 and the cooling water return control valve 18 are opened to allow cooling water to enter the storage space 6 to cool the distillation kettle 1 and press out the steam in advance to avoid the steam dissolving into the cooling water after the cooling water is injected into the storage space 6.

[0029] The utility model further comprises a discharge valve 15 and a centrifuge 16 for recovering the catalyst, one end of the discharge valve 15 is connected to the discharge port 1d, and the other end of the discharge valve 15 is connected to the centrifuge 16. After cooling the still 1, process water (the process water is tap water or deionized water) is added to the still 1, and a mixed solution is formed after stirring, and the mixed solution is transported to the centrifuge 16 through the discharge valve 15. Since there is a catalyst in the mixed solution (the catalyst is the catalyst that is put in the chiral propylene glycol synthesis stage), the centrifuge 16 is turned on to centrifuge the catalyst. After separation, the waste liquid is collected and then centrally processed, and the centrifuged catalyst is sent to the next step of activation treatment. The catalyst activation treatment is an existing method and will not be described in detail here.

[0030] The working process of the utility model is as follows:

[0031] S1, the first valve 7 and the second valve 8 are opened and the vacuum unit 9 is in working state. The negative pressure generated by the vacuum unit 9 causes the chiral propylene glycol in the chiral propylene glycol storage unit 5 to be input into the distillation kettle 1. After the loading is completed, the first valve 7 is closed to prepare for distillation.

[0032] S2, open the steam input control valve 10 and the steam output control valve 11, the steam in the first steam unit LS enters the containing space 6 through the steam input control valve 10 to heat the distillation kettle 1, open the second valve 8, the vacuum unit 9 is in working state, and the negative pressure generated by the vacuum unit 9 causes the distillation kettle 1 to enter the reduced pressure distillation. The gas generated by the distillation of chiral propylene glycol in the distillation kettle 1 enters the condenser 3, and the gas is liquefied by the condenser 3 to form chiral propylene glycol liquid, and the chiral propylene glycol liquid in the condenser 3 enters the propylene glycol receiving tank 4.

[0033] S3, after the distillation is finished, the steam input control valve 10 is closed, and the third valve 14 is opened. The compressed gas generated by the compressed gas supply unit 13 enters the storage space 6 through the third valve 14, so that the steam in the storage space 6 quickly flows back to the second steam unit SC. The steam output control valve 11 is closed, and the cooling water supply control valve 17 and the cooling water return control valve 18 are opened to allow cooling water to enter the storage space 6 to cool the distillation kettle 1. After the distillation kettle 1 is cooled, process water is added to the distillation kettle 1, and a mixed solution is formed after stirring. The mixed solution is conveyed to the centrifuge 16 through the discharge valve 15, and the centrifuge 16 is opened to centrifuge the catalyst. After separation, the waste liquid is collected and centralized for treatment, and the centrifuged catalyst is sent to the next step of activation treatment.

[0034] Finally, it should be noted that the above-described implementation mode is only a preferred embodiment of the utility model to illustrate the technical solution of the utility model, and does not limit it, let alone limit the protection scope of the utility model; although the utility model is described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the protection scope of the claims.

Claims

1. A chiral propylene glycol distillation device, comprising a still (1), a jacket (2), a steam input unit, a steam reflux unit, a condenser (3), a propylene glycol receiving tank (4), and a chiral propylene glycol storage unit (5); after the jacket (2) is matched with the still (1), a receiving space (6) is opened between the jacket (2) and the still (1); and the steam input unit and the steam reflux unit are respectively connected to the jacket (2); The upper part of the distillation kettle (1) is provided with a material input port (1a), a first output port (1b), and a second output port (1c), wherein the first output port (1b) is connected to the input end of the condenser (3), and the output end of the condenser (3) is connected to the propylene glycol receiving tank (4); the characteristic is that: The invention also comprises a first valve (7), a second valve (8), and a vacuum unit (9) for inputting chiral propylene glycol into the distillation kettle (1) and causing the distillation kettle (1) to form a reduced pressure distillation. One end of the first valve (7) is connected to the chiral propylene glycol storage unit (5), the other end of the first valve (7) is connected to the material input port (1a), one end of the second valve (8) is connected to the second output port (1c), and the other end of the second valve (8) is connected to the vacuum unit (9).

2. The chiral propylene glycol distillation apparatus according to claim 1, characterized in that: The steam input unit comprises a first steam unit (LS), a steam input control valve (10), a steam output control valve (11), and a second steam unit (SC); the output end of the first steam unit (LS) is connected to one end of the steam input control valve (10), the other end of the steam input control valve (10) is connected to an input port provided on the jacket (2), the output port provided on the jacket (2) is connected to one end of the steam output control valve (11), and the other end of the steam output control valve (11) is connected to the second steam unit (SC).

3. The chiral propylene glycol distillation apparatus according to claim 1, characterized in that: It also comprises a pipeline flame arrester (12) and a tail gas absorption unit (VT); one end of the pipeline flame arrester (12) is connected to the first output port (1b), and the other end of the pipeline flame arrester (12) is connected to the tail gas absorption unit (VT).

4. The chiral propylene glycol distillation apparatus according to claim 1, characterized in that: It also comprises a compressed gas supply unit (13) and a third valve (14), wherein the output end of the compressed gas supply unit (13) is connected to one end of the third valve (14), and the other end of the third valve (14) is connected to an input port provided on the jacket (2).

5. The chiral propylene glycol distillation apparatus according to claim 1, characterized in that: The distillation still (1) also comprises a discharge valve (15) and a centrifuge (16) for recovering the catalyst. A discharge port (1d) is provided at the lower part of the distillation still (1). One end of the discharge valve (15) is connected to the discharge port (1d), and the other end of the discharge valve (15) is connected to the centrifuge (16).

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