Dealcoholization device for dioctyl terephthalate

Abstract

The utility model belongs to the technical field of carbocyclic compounds, and particularly relates to a dioctyl terephthalate dealcoholization device which comprises a dealcoholization kettle, the dealcoholization kettle is connected with a dealcoholization stripping tower, a plurality of falling film tubes are arranged in the dealcoholization stripping tower, a redistributor is arranged at the top of the dealcoholization stripping tower, and a plurality of falling film tubes are arranged in the dealcoholization stripping tower. A plurality of drainage plates and a steam distributor are arranged at the bottom of the dealcoholization stripping tower, a dealcoholization storage tank is connected to the bottom of the dealcoholization stripping tower, a raw material sprayer, a steam ejector and a stirring assembly are arranged in the dealcoholization kettle, a compressor is arranged at the top of the dealcoholization stripping tower, a vacuum pump is connected to the top of the compressor, and a material cleaning arm is arranged in the dealcoholization storage tank. According to the dealcoholization device disclosed by the utility model, the continuous operation of the dealcoholization process is realized through twice dealcoholization operation, the dealcoholization time is shortened, the dealcoholization temperature is reduced, the high-temperature property change risk of dioctyl terephthalate is reduced, the dealcoholization treatment efficiency is improved, and the production efficiency is remarkably improved.

Description

Technical Field

[0001] This invention belongs to the field of carbocyclic compound technology, specifically relating to a de-alcoholization device for dioctyl terephthalate. Background Technology

[0002] Dioctyl terephthalate (DTP) is a high-performance plasticizer with high resistivity, high thermal stability, and low toxicity, making it widely used in the plastics processing industry. The preparation of DTP typically employs a direct esterification method. The resulting mixture contains excess octanol, requiring de-alcoholization to purify the product and recover the octanol for recycling. Traditional de-alcoholization devices often use stirred-tank evaporators or simple falling film evaporators. However, stirred-tank evaporators are inefficient and energy-intensive, and the long material residence time in stirred-tank evaporators requires prolonged high-temperature heating, which can easily lead to thermal decomposition of DTP, resulting in a darker product color and high energy consumption. Traditional falling film evaporators rely on gravity for film formation; for high-viscosity, easily coking materials like DTP, uneven liquid film distribution can lead to dry walls or scaling on the heating surface, rapidly reducing heat transfer efficiency. Rigid scraper evaporators, with their rigid scrapers in high-speed rotation and hard contact with the cylinder wall, are prone to wear and tear over long-term operation, generating metal shavings that contaminate the product.

[0003] Furthermore, existing dealcoholization units often suffer from limited stripping efficiency and high steam consumption when processing high-viscosity materials, indicating a need to improve energy utilization efficiency. Some units employ a single dealcoholization reactor or a single stripping tower, making it difficult to balance dealcoholization depth and production efficiency. This results in high residual alcohol content in the product after dealcoholization, affecting product purity. Utility Model Content

[0004] In view of the shortcomings of the prior art, the technical problem to be solved by this utility model is to provide a de-alcoholization device for dioctyl terephthalate, which removes octanol from dioctyl terephthalate and improves the de-alcoholization efficiency.

[0005] The technical solution adopted by this utility model to solve its technical problem is:

[0006] The de-alcoholization device for dioctyl terephthalate of this utility model includes a de-alcoholization kettle, a de-alcoholization stripping tower connected to the de-alcoholization kettle, a plurality of falling film tubes inside the de-alcoholization stripping tower, a redistributor at the top of the de-alcoholization stripping tower, a plurality of guide plates and a steam distributor at the bottom of the de-alcoholization stripping tower, a de-alcoholization storage tank connected to the bottom of the de-alcoholization stripping tower, a raw material sprayer, a steam ejector and a stirring assembly inside the de-alcoholization kettle, a compressor at the top of the de-alcoholization stripping tower, a vacuum pump connected to the top of the compressor, and a cleaning arm inside the de-alcoholization storage tank.

[0007] The top of the dehydrogenation reactor is provided with a raw material inlet, and a raw material sprayer is connected to the raw material inlet. The raw material sprayer is located above the steam ejector, and the top of the stirring assembly passes through the dehydrogenation reactor and is connected to a motor.

[0008] The stirring assembly includes an arc-shaped stirring rod and an inclined stirring rod, with the arc-shaped stirring rod located above the inclined stirring rod.

[0009] The raw material sprayer is arranged in a ring shape, the stirring component passes through the middle of the raw material sprayer, and the stirring component is located above the steam ejector.

[0010] The raw material sprayer has several spray nozzles at its bottom, and the density of the spray nozzles on the inner side of the raw material sprayer is greater than that on the outer side.

[0011] The dehydrogenation vessel is equipped with an insulation sleeve, and the top of the dehydrogenation vessel is connected to the compressor.

[0012] The redistributor is located above the falling film pipe, the steam distributor, and the guide plate. The falling film pipe is located above the steam distributor and the guide plate, and the steam distributor is located above the guide plate.

[0013] The aforementioned guide plates are spaced apart on the inner wall of the deethanolating stripper, with the guide plates inclined inward and the bottom of the guide plates close to the middle of the deethanolating stripper.

[0014] The middle part of the deethanolating stripping tower is connected to the upper part of the deethanolating storage tank.

[0015] The cleaning arm is designed to fit the inner wall of the deethanolating tank. An electric push rod is installed at the top of the cleaning arm, and the electric push rod passes through the deethanolating tank and is connected to a motor.

[0016] The beneficial effects of this utility model are:

[0017] This invention achieves continuous operation of the de-alcoholization process through two de-alcoholization operations, shortening the de-alcoholization time and lowering the de-alcoholization temperature, reducing the risk of high-temperature denaturation of dioctyl terephthalate, and improving de-alcoholization efficiency, thus significantly increasing production efficiency. The stirring components and steam ejectors in the de-alcoholization kettle enhance mass transfer through stirring, and combined with steam stripping, can remove most of the free octyl alcohol from the material. The de-alcoholization stripping tower is equipped with falling film tubes, a steam distributor, and a redistributor for deep de-alcoholization treatment of the material. The synergistic effect of these two components results in good de-alcoholization effect and high product purity. After the material enters the de-alcoholization stripping tower, a thin film layer forms on the surface of the falling film tube, increasing the gas-liquid contact area. Combined with saturated steam stripping, residual alcohol can be efficiently removed, reducing the alcohol content in the de-alcoholized product. The de-alcoholization kettle adopts a single-shaft double-stirring rod structure, which enhances the vertical mixing and heat transfer of high-viscosity materials, making the material dispersed and heated evenly, increasing the steam contact area. The compressor and vacuum pump compress and separate the distilled octyl alcohol for recycling, reducing production costs. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model;

[0019] Figure 2 This is a schematic diagram of the falling film tube structure of this utility model;

[0020] Figure 3 This is a schematic diagram of the stirring assembly structure of this utility model;

[0021] Figure 4 This is a schematic diagram of the raw material sprayer structure of this utility model;

[0022] Figure 5 This is a schematic diagram of part of the drainage plate structure of this utility model;

[0023] In the diagram: 1. Deethanolating vessel; 2. Deethanolating stripping tower; 3. Deethanolating storage tank; 4. Compressor; 5. Falling film pipe; 6. Vacuum pump; 7. Raw material inlet; 8. Stirring assembly; 9. Raw material sprayer; 10. Steam ejector; 11. Cleaning arm; 12. Electric push rod; 13. Redistributor; 14. Drain plate; 15. Steam distributor; 101. Insulation jacket; 801. Arc-shaped stirring rod; 802. Inclined stirring rod. Detailed Implementation

[0024] The embodiments of this utility model will be further described below with reference to the accompanying drawings.

[0025] Example 1

[0026] like Figure 1-5 As shown, the de-alcoholization device for dioctyl terephthalate of this utility model includes a de-alcoholization kettle 1, a de-alcoholization stripping tower 2 connected to the de-alcoholization kettle 1, a plurality of falling film tubes 5 inside the de-alcoholization stripping tower 2, a redistributor 13 at the top of the de-alcoholization stripping tower 2, a plurality of guide plates 14 and a steam distributor 15 at the bottom of the de-alcoholization stripping tower 2, a de-alcoholization storage tank 3 connected to the bottom of the de-alcoholization stripping tower 2, a raw material sprayer 9, a steam ejector 10 and a stirring assembly 8 inside the de-alcoholization kettle 1, a compressor 4 at the top of the de-alcoholization stripping tower 2, a vacuum pump 6 connected to the top of the compressor 4, and a cleaning arm 11 inside the de-alcoholization storage tank 3.

[0027] The top of the deethanolating kettle 1 is provided with a raw material inlet 7, and the raw material sprayer 9 is connected to the raw material inlet 7. The raw material sprayer 9 is located above the steam ejector 10, and the top of the stirring assembly 8 passes through the deethanolating kettle 1 and is connected to a motor.

[0028] The stirring assembly 8 includes an arc-shaped stirring rod 801 and an inclined stirring rod 802, with the arc-shaped stirring rod 801 located above the inclined stirring rod 802.

[0029] The raw material sprayer 9 is arranged in a ring shape, the stirring component 8 passes through the middle of the raw material sprayer 9, and the stirring component 8 is located above the steam ejector 10.

[0030] The bottom of the raw material sprayer 9 is provided with several spray nozzles, and the density of the spray nozzles on the inner side of the raw material sprayer 9 is greater than that on the outer side.

[0031] The exterior of the dehydrogenation vessel 1 is equipped with an insulation sleeve 101, and the top of the dehydrogenation vessel 1 is connected to the compressor 4.

[0032] The redistributor 13 is located above the falling film tube 5, the steam distributor 15 and the guide plate 14. The falling film tube 5 is located above the steam distributor 15 and the guide plate 14. The steam distributor 15 is located above the guide plate 14.

[0033] Several guide plates 14 are spaced apart on the inner wall of the deethanolating stripping tower 2. The guide plates 14 are inclined inward and the bottom of the guide plates 14 is close to the middle of the deethanolating stripping tower 2.

[0034] The middle part of the alcohol stripping tower 2 is connected to the upper part of the alcohol storage tank 3.

[0035] The cleaning arm 11 is installed in conjunction with the inner wall of the deethanolating tank 3. An electric push rod 12 is installed at the top of the cleaning arm 11, and the electric push rod 12 passes through the deethanolating tank 3 and is connected to a motor.

[0036] Working principle and process:

[0037] The prepared crude dioctyl terephthalate is transported into the dealcoholization reactor 1 and evenly sprayed by the raw material sprayer 9. Then, the motor is turned on to rotate the stirring assembly 8. The arc-shaped stirring rod 801 further agitates the sprayed crude dioctyl terephthalate, causing the droplets to fall in an umbrella-like pattern onto the inner wall of the dealcoholization reactor 1. Simultaneously, high-temperature steam is supplied into the dealcoholization reactor 1. After being dispersed by the steam injector 10, the high-temperature steam can fully contact the crude dioctyl terephthalate droplets. The crude dioctyl terephthalate that falls to the bottom of the dealcoholization reactor 1 is further stirred by the inclined stirring rod 802, achieving the discharge of octyl alcohol. The processed crude dioctyl terephthalate is then transported to the dealcoholization stripping tower 2 for further de-oxidation. High-temperature steam enters the stripping tower 2 from the bottom and contacts the redistributed crude dioctyl terephthalate on the falling film tube 5, carrying away the residual octyl terephthalate. The compressor 4 and vacuum pump 6 connected to the top of the stripping tower 2 and the top of the stripping kettle 1 work together to achieve rapid extraction of octyl terephthalate and steam, improving the stripping efficiency of dioctyl terephthalate. After stripping, the dioctyl terephthalate is guided by the guide plate 14 and forms a vortex at the bottom of the stripping tower 2, which can be quickly transported to the stripping storage tank 3 for storage and further processing. The cleaning arm 11 in the stripping storage tank 3 can remove the residual liquid on the inner wall of the stripping storage tank 3, improving the yield of dioctyl terephthalate.

Claims

1. A dealcoholation device of dioctyl terephthalate comprising a dealcoholation kettle (1), characterized in that, The alcohol removal vessel (1) is connected to the alcohol removal stripping tower (2). The alcohol removal stripping tower (2) is equipped with several falling film tubes (5). The top of the alcohol removal stripping tower (2) is equipped with a redistributor (13). The bottom of the alcohol removal stripping tower (2) is equipped with several guide plates (14) and a steam distributor (15). The bottom of the alcohol removal stripping tower (2) is connected to the alcohol removal storage tank (3). The alcohol removal vessel (1) is equipped with a raw material sprayer (9), a steam ejector (10) and a stirring assembly (8). The top of the alcohol removal stripping tower (2) is equipped with a compressor (4). The top of the compressor (4) is connected to a vacuum pump (6). The alcohol removal storage tank (3) is equipped with a cleaning arm (11).

2. The dealcoholation apparatus of dioctyl terephthalate according to claim 1, characterized by, The top of the deethanolating kettle (1) is provided with a raw material inlet (7), and the raw material sprayer (9) is connected to the raw material inlet (7). The raw material sprayer (9) is located above the steam ejector (10). The top of the stirring assembly (8) passes through the deethanolating kettle (1) and is connected to a motor.

3. The dealcoholation apparatus of dioctyl terephthalate according to claim 1, characterized by, The stirring assembly (8) includes an arc-shaped stirring rod (801) and an inclined stirring rod (802), with the arc-shaped stirring rod (801) located above the inclined stirring rod (802).

4. The dealcoholation apparatus of dioctyl terephthalate according to claim 1, characterized by, The raw material sprayer (9) is arranged in a ring shape, the stirring component (8) passes through the middle of the raw material sprayer (9), and the stirring component (8) is located above the steam ejector (10).

5. The dealcoholation apparatus of dioctyl terephthalate according to claim 4, characterized by, The bottom of the raw material sprayer (9) is provided with several spray nozzles, and the density of the spray nozzles on the inner side of the raw material sprayer (9) is greater than that on the outer side.

6. The dealcoholation apparatus of dioctyl terephthalate according to claim 1, characterized by, The alcohol removal vessel (1) is equipped with an insulation sleeve (101) on the outside, and the top of the alcohol removal vessel (1) is connected to the compressor (4).

7. The de-alcoholization apparatus for dioctyl terephthalate according to claim 1, characterized in that, The redistributor (13) is located above the falling film tube (5), the steam distributor (15) and the guide plate (14). The falling film tube (5) is located above the steam distributor (15) and the guide plate (14). The steam distributor (15) is located above the guide plate (14).

8. The dealcoholation apparatus of dioctyl terephthalate according to claim 1, characterized by, Several guide plates (14) are spaced apart on the inner wall of the deethanolating stripping tower (2), with the bottom of the guide plates (14) being close to the middle of the deethanolating stripping tower (2).

9. The de-alcoholization apparatus of dioctyl terephthalate according to claim 1, characterized by, The middle part of the deethanolating stripping tower (2) is connected to the upper part of the deethanolating storage tank (3).

10. The dealcoholation apparatus of dioctyl terephthalate according to claim 1, characterized by, The cleaning arm (11) is installed in conjunction with the inner wall of the deethanolating tank (3). An electric push rod (12) is installed at the top of the cleaning arm (11). The electric push rod (12) passes through the deethanolating tank (3) and is connected to a motor.

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