A purified terephthalic acid distillation apparatus

Abstract

This utility model discloses a purified terephthalic acid distillation apparatus, comprising a distillation column, a first condenser column, and a second condenser column. The top of the distillation column is provided with a first exhaust pipe and a second exhaust pipe. The first exhaust pipe is connected to the first condenser column, and the second exhaust pipe is connected to the second condenser column. A lifting platform is provided inside the distillation column, and the lifting platform is equipped with several evaporation plates. When the lifting platform moves up and down, it causes the evaporation plates to be submerged below the liquid surface and extended above the liquid surface. This utility model provides a purified terephthalic acid distillation apparatus that utilizes the raising and lowering of the evaporation plates to increase the evaporation area. While improving evaporation efficiency, it minimizes airflow, and the temperature plays a major role in the evaporation process, allowing for more effective separation of components with different boiling points.

Description

Technical Field

[0001] This utility model relates to the field of purified terephthalic acid technology, and in particular to a purified terephthalic acid distillation apparatus. Background Technology

[0002] In the removal of moisture and benzoic acid impurities from purified terephthalic acid, a two-stage distillation process is required using a distillation column: a dehydration step at 80–120°C, followed by further separation of benzoic acid at 180–250°C. In existing distillation techniques, relying solely on surface evaporation to separate different components is inefficient. While stirring can accelerate evaporation, this increases the flow rate between the liquid surface and air, leading to accelerated evaporation of components with different boiling points and hindering effective separation. Utility Model Content

[0003] In view of the above-mentioned prior art, the present invention provides a purified terephthalic acid distillation apparatus, which utilizes the raising and lowering of the evaporation plate to increase the evaporation area, thereby improving evaporation efficiency while minimizing airflow. Temperature plays a major role in the evaporation process, allowing for more effective separation of components with different boiling points.

[0004] To achieve the above objectives, the technical solution of this utility model embodiment is implemented as follows:

[0005] A purified terephthalic acid distillation apparatus includes a distillation column, a first condenser column, and a second condenser column. The top of the distillation column is provided with a first exhaust pipe and a second exhaust pipe. The first exhaust pipe is connected to the first condenser column, and the second exhaust pipe is connected to the second condenser column. A lifting platform is provided inside the distillation column. The lifting platform is provided with a plurality of evaporation plates. When the lifting platform is raised and lowered, it causes the evaporation plates to be submerged below the liquid surface and extended above the liquid surface.

[0006] Furthermore, the lifting platform includes a telescopic rod and a connecting frame. The upper end of the telescopic rod is connected to the top of the distillation column, and the lower end of the telescopic rod is provided with the connecting frame, which is connected to the evaporation plate.

[0007] Furthermore, the evaporation plate is spiral-shaped, the top of the evaporation plate is connected to the connecting frame, and adjacent evaporation plates are connected to each other by connecting rods.

[0008] Furthermore, the connecting frame includes a horizontal mesh frame and a vertical rod. The horizontal mesh frame is connected to the telescopic rod, and the vertical rod is fixed to the bottom of the horizontal mesh frame. The bottom of the vertical rod is connected to the evaporation plate.

[0009] Furthermore, both the first exhaust pipe and the second exhaust pipe are equipped with control valves.

[0010] Furthermore, the telescopic rod is an electric telescopic rod, a pneumatic telescopic rod, or a hydraulic telescopic rod. The telescopic rod is located outside the distillation column. The top of the distillation column is provided with a first through hole. The lower end of the telescopic rod is connected to the connecting frame through a transmission rod. A sealing ring is provided on the side of the first through hole.

[0011] Furthermore, the top of the distillation column is provided with a mounting base, and the telescopic rod is fixedly connected to the mounting base.

[0012] Furthermore, the side of the first through hole is provided with a first annular groove and a second annular groove, and the sealing ring is provided in both the first annular groove and the second annular groove.

[0013] Furthermore, the top of the distillation column is provided with a boss, the boss is provided with an external thread, the boss is threadedly connected to a dust cap, and the dust cap is provided with a second through hole passing through the transmission rod.

[0014] Furthermore, a sealing ring is provided above the boss, and the dust cap presses against the sealing ring.

[0015] The beneficial effects of this invention are as follows: During the heating process, the lifting platform drives the evaporating plate to move up and down reciprocally. When the evaporating plate enters below the liquid surface in the distillation column, the liquid surface adheres to the surface of the evaporating plate. After the lifting platform rises, the evaporating plate moves above the liquid surface, thereby increasing the surface area and improving the distillation efficiency. By increasing the evaporation surface area through the lifting of the platform, airflow can be minimized while improving evaporation efficiency. Temperature plays a major role in the evaporation process, allowing for more effective separation of components with different boiling points. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a purified terephthalic acid distillation apparatus according to an embodiment of this application.

[0017] Figure 2 For this application Figure 1 A magnified structural diagram of region A in the middle.

[0018] Explanation of icon numbers:

[0019] 1. Distillation column; 2. First condenser; 3. Second condenser; 4. First exhaust pipe; 5. Second exhaust pipe; 6. Lifting platform; 7. Evaporator plate; 8. Telescopic rod; 9. Connecting frame; 10. Connecting rod; 11. Horizontal grid frame; 12. Vertical rod; 13. Control valve; 14. Transmission rod; 15. Sealing ring; 16. Mounting base; 17. First annular groove; 18. Second annular groove; 19. Boss; 20. External thread; 21. Dust cap; 22. Second through hole; 23. First through hole. Detailed Implementation

[0020] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used in this specification of this utility model is for the purpose of describing particular embodiments only and is not intended to limit the utility model. In the following description, the expression "some embodiments" refers to a subset of all possible embodiments; however, it should be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments and can be combined with each other without conflict.

[0021] It should also be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "inner," "outer," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0022] Example 1

[0023] Please refer to the attached document. Figures 1-2This application provides a purified terephthalic acid distillation apparatus, including a distillation column 1, a first condenser column 2, and a second condenser column 3. The top of the distillation column 1 is provided with a first exhaust pipe 4 and a second exhaust pipe 5. The first exhaust pipe 4 is connected to the first condenser column 2, and the second exhaust pipe 5 is connected to the second condenser column 3. A lifting platform 6 is provided inside the distillation column 1, and the lifting platform 6 is equipped with several evaporation plates 7. When the lifting platform 6 moves up and down, it causes the evaporation plates 7 to be submerged below the liquid surface and extended above the liquid surface. Purified terephthalic acid containing impurities is placed in the distillation column 1 and distilled using the distillation column 1. The temperature inside the distillation column 1 is heated to 80-120°C for a dehydration step. The evaporated water vapor enters the first condenser column 2 through the first exhaust pipe 4. Next, the remaining material in distillation column 1 is heated to 180–250°C to further separate benzoic acid. The evaporated benzoic acid enters the second condenser 3 through the second exhaust pipe 5 for condensation, ultimately yielding purified terephthalic acid with improved purity in distillation column 1. During the heating process, the lifting platform 6 drives the evaporating plate 7 to move up and down reciprocally. When the evaporating plate 7 is below the liquid surface in distillation column 1, the liquid adheres to its surface. After the lifting platform 6 rises, the evaporating plate 7 moves above the liquid surface, thereby increasing the surface area and improving distillation efficiency. By raising and lowering the lifting platform 6 to increase the evaporation surface area, airflow can be minimized while improving evaporation efficiency. Temperature plays a major role in the evaporation process, allowing for more effective separation of components with different boiling points.

[0024] Specifically, the lifting platform 6 includes a telescopic rod 8 and a connecting frame 9. The upper end of the telescopic rod 8 is connected to the top of the distillation column 1, and the lower end of the telescopic rod 8 is provided with the connecting frame 9, which is connected to the evaporation plate 7. The evaporation plate 7 is fixed on the connecting frame 9, and the connecting frame 9 is fixedly connected to the telescopic rod 8. When the telescopic rod 8 extends or retracts, it drives the connecting frame 9 and the evaporation plate 7 to move up and down, thereby immersing the evaporation plate 7 in the liquid and lifting the evaporation plate 7 with liquid attached to it above the liquid surface.

[0025] Specifically, the evaporation plate 7 is spiral-shaped, with its top connected to the connecting frame 9, and adjacent evaporation plates 7 connected to each other via connecting rods 10. The spiral shape of the evaporation plate 7 reduces liquid reflux, increases liquid residence time, and promotes the evaporation and separation of impurities in purified terephthalic acid. The bottoms of the evaporation plates 7 are connected to each other via connecting rods 10, improving the structural stability of the evaporation plates 7.

[0026] Specifically, the connecting frame 9 includes a horizontal mesh frame 11 and a vertical rod 12. The horizontal mesh frame 11 is connected to the telescopic rod 8, and the vertical rod 12 is fixed to the bottom of the horizontal mesh frame 11. The bottom of the vertical rod 12 is connected to the evaporation plate 7. The evaporated vapor can pass through the first through hole 23 of the horizontal mesh frame 11. The evaporation plate 7 is connected to the horizontal mesh frame 11, and when the evaporation plate 7 is submerged, the horizontal mesh frame 11 is positioned above the liquid surface. The horizontal mesh frame 11 has a stable structure and can stably connect the evaporation plate 7.

[0027] Specifically, both the first exhaust pipe 4 and the second exhaust pipe 5 are equipped with control valves 13. During the dehydration step, the control valve 13 on the first exhaust pipe 4 is opened, while the control valve 13 on the second exhaust pipe 5 is closed. During the separation of benzoic acid, the control valve 13 on the first exhaust pipe 4 is closed, while the control valve 13 on the second exhaust pipe 5 is opened.

[0028] Example 2

[0029] Please refer to the attached document. Figures 1-2 The difference between this embodiment and Embodiment 1 is that the telescopic rod 8 is an electric, pneumatic, or hydraulic telescopic rod. The telescopic rod 8 is located outside the distillation column 1. The top of the distillation column 1 has a first through hole 23. The lower end of the telescopic rod 8 is connected to the connecting frame 9 via a transmission rod 14. A sealing ring 15 is provided on the side of the first through hole 23. The telescopic rod 8 being located outside the distillation column 1 prevents damage from the high temperatures inside the column. The bottom of the telescopic rod 8 is connected to the connecting frame 9 inside the distillation column 1 via the transmission rod 14, which drives the connecting frame 9 to move up and down. The top of the distillation column 1 has a first through hole 23. The transmission rod 14 passes through the first through hole 23 and enters the distillation column 1. A sealing ring 15 is provided on the side of the first through hole 23 to ensure the sealing of the distillation column 1 when the transmission rod 14 moves up and down.

[0030] Specifically, the top of the distillation column 1 is provided with a mounting base 16, and the telescopic rod 8 is fixedly connected to the mounting base 16. The mounting base 16 is used to install the telescopic rod 8, thereby improving the stability of the telescopic rod 8.

[0031] Specifically, the side of the first through hole 23 is provided with a first annular groove 17 and a second annular groove 18, and the sealing ring 15 is provided in both the first annular groove 17 and the second annular groove 18. The two sealing rings 15 are provided at the position of the transmission rod 14 to improve the sealing performance of the first through hole 23. The first annular groove 17 and the second annular groove 18 restrict the movement of the sealing rings 15, preventing the sealing rings 15 from moving axially when the transmission rod 14 moves up and down.

[0032] Specifically, the top of the distillation column 1 is provided with a boss 19, which has an external thread 20. The boss 19 is threadedly connected to a dust cap 21, and the dust cap 21 has a second through hole 22 through which the transmission rod 14 passes. The dust cap 21 on the boss 19 prevents dust from entering the first through hole 23.

[0033] Specifically, a sealing ring 15 is provided above the boss 19, and the dust cap 21 presses against the sealing ring 15. A sealing ring 15 is also provided below the dust cap 21, and the sealing ring 15 is sandwiched between the dust cap 21 and the boss 19, which can further improve the dustproof effect.

[0034] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. The protection scope of this utility model should be determined by the protection scope of the stated claims.

Claims

1. A purified terephthalic acid distillation apparatus, characterized in that, The distillation column (1), the first condenser (2), and the second condenser (3) are included. The top of the distillation column (1) is provided with a first exhaust pipe (4) and a second exhaust pipe (5). The first exhaust pipe (4) is connected to the first condenser (2), and the second exhaust pipe (5) is connected to the second condenser (3). The distillation column (1) is provided with a lifting platform (6). The lifting platform (6) is provided with several evaporation plates (7). When the lifting platform (6) is raised and lowered, it causes the evaporation plates (7) to be submerged below the liquid surface and extended above the liquid surface.

2. The purified terephthalic acid distillation apparatus according to claim 1, characterized in that, The lifting platform (6) includes a telescopic rod (8) and a connecting frame (9). The upper end of the telescopic rod (8) is connected to the top of the distillation column (1), and the lower end of the telescopic rod (8) is provided with the connecting frame (9). The connecting frame (9) is connected to the evaporation plate (7).

3. The purified terephthalic acid distillation apparatus according to claim 2, characterized in that, The evaporation plate (7) is spiral-shaped, and the top of the evaporation plate (7) is connected to the connecting frame (9). Adjacent evaporation plates (7) are connected to each other by connecting rods (10).

4. The purified terephthalic acid distillation apparatus according to claim 2, characterized in that, The connecting frame (9) includes a horizontal mesh frame (11) and a vertical rod (12). The horizontal mesh frame (11) is connected to the telescopic rod (8). The vertical rod (12) is fixed to the bottom of the horizontal mesh frame (11). The bottom of the vertical rod (12) is connected to the evaporation plate (7).

5. The purified terephthalic acid distillation apparatus according to claim 1, characterized in that, The first exhaust pipe (4) and the second exhaust pipe (5) are both equipped with control valves (13).

6. The purified terephthalic acid distillation apparatus according to claim 2, characterized in that, The telescopic rod (8) is an electric telescopic rod, a pneumatic telescopic rod, or a hydraulic telescopic rod. The telescopic rod (8) is located outside the distillation column (1). The top of the distillation column (1) is provided with a first through hole (23). The lower end of the telescopic rod (8) is connected to the connecting frame (9) through a transmission rod (14). A sealing ring (15) is provided on the side of the first through hole (23).

7. The purified terephthalic acid distillation apparatus according to claim 2, characterized in that, The top of the distillation column (1) is provided with a mounting base (16), and the telescopic rod (8) is fixedly connected to the mounting base (16).

8. The purified terephthalic acid distillation apparatus according to claim 6, characterized in that, The first through hole (23) has a first annular groove (17) and a second annular groove (18) on its side, and the sealing ring (15) is provided in both the first annular groove (17) and the second annular groove (18).

9. The purified terephthalic acid distillation apparatus according to claim 6, characterized in that, The top of the distillation column (1) is provided with a boss (19), and the boss (19) is provided with an external thread (20). The boss (19) is threadedly connected to a dust cap (21), and the dust cap (21) is provided with a second through hole (22) passing through the transmission rod (14).

10. The purified terephthalic acid distillation apparatus according to claim 9, characterized in that, A sealing ring (15) is provided above the boss (19), and the dust cap (21) presses the sealing ring (15) tightly.

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