Rectifying tower for purifying and recycling THF residual liquid

Abstract

The utility model discloses a rectifying tower for purifying and recycling THF (tetrahydrofuran) residual liquid, which comprises a rectifying tower body, a liquid inlet pipe is fixedly mounted in the middle of the rectifying tower body, tower plates are fixedly mounted in the middle of the rectifying tower body at equal intervals, and overflow weir plates are fixedly mounted on the upper surfaces of the tower plates. A water falling area is formed between the overflow weir plate and the inner wall of the rectifying tower body, THF residual liquid descends to the tower plate on the next layer through the first downcast pipe and the second downcast pipe, the THF residual liquid descends through the first downcast holes in the first downcast pipe and the second downcast holes in the second downcast pipe, the contact area between the THF residual liquid and heated air is increased, and therefore the THF residual liquid can be heated. According to the THF residual liquid purifying device, the effect of purifying 2-methyltetrahydrofuran and 3-methyltetrahydrofuran in THF residual liquid is improved, meanwhile, when the THF residual liquid flows through the horizontal end of the top end of the second downcast pipe, fan blades at the bottom end of a rotating shaft are pushed by the THF residual liquid, the rotating shaft is driven to rotate and ascend and descend in a reciprocating mode, the THF residual liquid on a tower plate can be stirred up and down, and the purifying effect is further improved.

Description

Technical Field

[0001] The utility model relates to the technical field of rectification, in particular to a rectification column for purifying and recycling THF residue liquid. Background Technique

[0002] Tetrahydrofuran (THF), also known as oxolane and 1,4-epoxybutane, is a heterocyclic organic compound, which is a colorless and transparent liquid. It is mainly used as a solvent, a chemical synthesis intermediate and an analytical reagent. The THF synthesis residue liquid comes from the bottom of the third rectification column for dehydrating BDO to produce THF. Due to incomplete chemical reactions or waste water discharge in the process, THF residue liquid is formed. The main components of THF residue liquid include THF, 2-methyltetrahydrofuran, 3-methyltetrahydrofuran and other components. In order to extract and recycle 2-methyltetrahydrofuran and 3-methyltetrahydrofuran in the residue liquid, it is necessary to rectify and purify the THF residue liquid.

[0003] In the prior art, usually the THF residue liquid enters the topmost tray from the middle of the rectification column. After the liquid is higher than the overflow weir, it falls to the next tray. At the same time, the vapor enters from the bottom of the column. The evaporated gas phase contacts the descending liquid in a countercurrent manner. The volatile components in the descending liquid are continuously transferred to the gas phase, and the non-volatile components in the gas phase are continuously transferred to the descending liquid, so as to achieve the purpose of component separation. However, since 2-methyltetrahydrofuran and 3-methyltetrahydrofuran in the THF residue liquid are isomers with close boiling points and are difficult to separate, the effect of purifying 2-methyltetrahydrofuran and 3-methyltetrahydrofuran in the THF residue liquid by the prior art is poor, resulting in a low purification concentration of 2-methyltetrahydrofuran and 3-methyltetrahydrofuran. Content of the Utility Model

[0004] The purpose of the utility model is to provide a rectification column for purifying and recycling THF residue liquid to solve the problems put forward in the above background technique.

[0005] To achieve the above purpose, the utility model provides the following technical solution: a rectification column for purifying and recycling THF residue liquid, including a rectification column body. A liquid inlet pipe is fixedly installed in the middle of the rectification column body. Trays are fixedly installed at equal intervals in the middle of the rectification column body. An overflow weir plate is fixedly installed on the upper surface of the tray. A water falling area is formed between the overflow weir plate and the inner wall of the rectification column body. First water discharge pipes are fixedly installed at equal intervals and symmetrically at positions corresponding to the water falling area of the tray. First water discharge holes are opened at equal intervals below the bottom ends of the first water discharge pipes. A rotating shaft is rotatably installed in the middle of the tray, and a stirring blade is fixedly installed at the top of the rotating shaft.

[0006] As a further preference of the technical solution, a fan blade is fixedly installed at the bottom end of the rotating shaft. A second downcomer is fixedly installed at the middle position of the tray corresponding to the water falling area. The bottom end of the second downcomer is equidistantly provided with second water precipitation holes. The fan blade is arranged inside the horizontal end at the top of the second downcomer.

[0007] As a further preference of the technical solution, a mounting pipe is rotatably installed in the middle of the tray through a sealed bearing. The rotating shaft is slidably installed inside the mounting pipe. The inner wall of the mounting pipe is symmetrically provided with limiting grooves. The outer side of the rotating shaft is symmetrically fixedly installed with limiting blocks. The limiting blocks are slidably connected with the limiting grooves.

[0008] As a further preference of the technical solution, a mounting plate is fixedly installed at the top of the rotating shaft. The lower surface of the mounting plate is fixedly installed with arc-shaped triangular plates in an annular array around the central axis of the mounting plate. An extrusion column is fixedly installed at the middle position of the upper surface of the tray corresponding to the arc-shaped triangular plates. The extrusion column is in extrusion contact with the arc-shaped triangular plates.

[0009] As a further preference of the technical solution, a return spring is sleeved on the outer side of the bottom end of the rotating shaft. One end of the return spring is fixedly connected with the bottom end of the mounting pipe, and the other end of the return spring is fixedly connected with the outer wall of the rotating shaft.

[0010] As a further preference of the technical solution, the top of the overflow weir plate is higher than the stirring blade.

[0011] The utility model provides a distillation column for purifying and recycling THF residue liquid, and has the following beneficial effects:

[0012] () In the utility model, the THF residue liquid is conveyed into the distillation column body through the liquid inlet pipe. The THF residue liquid is conveyed to the topmost tray. When the THF residue liquid exceeds the overflow weir plate, the THF residue liquid will descend to the next lower tray through the first downcomer and the second downcomer. The THF residue liquid will fall through the first water precipitation holes on the first downcomer and the second water precipitation holes on the second downcomer, which will increase the contact area between the THF residue liquid and the heated air and improve the purification effect of 2-methyltetrahydrofuran and 3-methyltetrahydrofuran in the THF residue liquid.

[0013] (2) In the utility model, the THF residue liquid is conveyed down to the next lower tray through the first downcomer and the second downcomer. When the THF residue liquid flows through the horizontal end at the top of the second downcomer, the THF residue liquid will push the fan blade at the bottom end of the rotating shaft, which will drive the rotation and reciprocating lifting of the rotating shaft, and can stir the THF residue liquid on the tray up and down, further improving the purification effect. Description of the Drawings

[0014] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0015] Figure 2 is the overall sectional structure schematic diagram of the present utility model;

[0016] Figure 3 is the partial sectional structure schematic diagram of the present utility model;

[0017] Figure 4 is the partial sectional explosion structure schematic diagram of the present utility model;

[0018] Figure 5 is Figure 4 the enlarged view of position A in

[0019] In the figure: 1, rectifying tower body; 2, liquid inlet pipe; 3, tray; 4, overflow weir plate; 5, falling water area; 6, first downcomer; 7, first precipitation hole; 8, rotating shaft; 9, stirring blade; 10, fan blade; 11, second downcomer; 12, second precipitation hole; 13, installation pipe; 14, limiting groove; 15, limiting block; 16, mounting plate; 17, arc triangular plate; 18, extrusion column; 19, return spring. Specific embodiments

[0020] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model.

[0021] The present utility model provides a technical solution: As Figures 1 to 5 shown, in this embodiment, a rectifying tower for THF residue purification and recovery includes a rectifying tower body 1. A liquid inlet pipe 2 is fixedly installed in the middle of the rectifying tower body 1. Trays 3 are fixedly installed equidistantly in the middle of the rectifying tower body 1. An overflow weir plate 4 is fixedly installed on the upper surface of the tray 3. A falling water area 5 is formed between the overflow weir plate 4 and the inner wall of the rectifying tower body 1. First downcomers 6 are fixedly installed equidistantly and symmetrically at positions corresponding to the falling water area 5 on the tray 3. First precipitation holes 7 are opened equidistantly below the bottom ends of the first downcomers 6. A rotating shaft 8 is rotatably installed in the middle of the tray 3. A stirring blade 9 is fixedly installed at the top of the rotating shaft 8. The THF residue is conveyed into the rectifying tower body 1 through the liquid inlet pipe 2. The THF residue will be conveyed to the topmost tray 3. When the THF residue exceeds the overflow weir plate 4, the THF residue will drop to the next lower tray 3 through the first downcomers 6. The THF residue will fall through the first precipitation holes 7 on the first downcomers 6, which will increase the contact area between the THF residue and the heated air and improve the purification effect of 2-methyltetrahydrofuran and 3-methyltetrahydrofuran in the THF residue;

[0022] When the THF residual liquid is transported to the next tray 3, the flow of the THF residual liquid will control the rotation and lifting of the rotating shaft 8, drive the stirring blade 9 to rotate and lift, and can stir the THF residual liquid on the tray 3, improving the contact effect between the THF residual liquid and the heated air and enhancing the purification effect.

[0023] As Figures 1 to 5 shown, a fan blade 10 is fixedly installed at the bottom end of the rotating shaft 8, and a second downcomer 11 is fixedly installed at the middle position of the tray 3 corresponding to the water falling area 5. The bottom end of the second downcomer 11 is equidistantly provided with second water falling holes 12, and the fan blade 10 is arranged inside the top horizontal end of the second downcomer 11.

[0024] When the THF residual liquid exceeds the overflow weir plate 4, the THF residual liquid will descend to the next tray 3 through the second downcomer 11, and the THF residual liquid will fall through the second water falling holes 12 on the second downcomer 11, also increasing the contact area between the THF residual liquid and the heated air and enhancing the purification effect of 2-methyltetrahydrofuran and 3-methyltetrahydrofuran in the THF residual liquid. When the THF residual liquid flows through the top horizontal end of the second downcomer 11, the THF residual liquid will push the fan blade 10 at the bottom end of the rotating shaft 8, drive the rotating shaft 8 to rotate, drive the stirring blade 9 to rotate, and can stir the THF residual liquid on the tray 3, improving the contact effect between the THF residual liquid and the heated air and enhancing the purification effect.

[0025] As Figures 1 to 5 shown, a mounting pipe 13 is rotatably installed in the middle of the tray 3 through a sealed bearing, the rotating shaft 8 is slidably installed inside the mounting pipe 13, the inner wall of the mounting pipe 13 is symmetrically provided with limiting grooves 14, and symmetrically fixed limit blocks 15 are installed on the outer side of the rotating shaft 8. The limit blocks 15 are slidably connected with the limiting grooves 14.

[0026] When the rotating shaft 8 rotates, the limiting of the limiting groove 14 on the mounting pipe 13 by the limit block 15 on the rotating shaft 8 will drive the mounting pipe 13 to rotate synchronously.

[0027] As Figures 1 to 5 shown, a mounting plate 16 is fixedly installed at the top of the rotating shaft 8, and arc-shaped triangular plates 17 are fixedly installed on the lower surface of the mounting plate 16 in an annular array with the central axis of the mounting plate 16 as the axis. An extrusion column 18 is fixedly installed at the middle position of the upper surface of the tray 3 corresponding to the arc-shaped triangular plates 17. The extrusion column 18 is in extrusion contact with the arc-shaped triangular plates 17.

[0028] When the rotating shaft 8 rotates, the arc-shaped triangular plates 17 below the mounting plate 16 at the top of the rotating shaft 8 will squeeze the extrusion column 18, which can drive the rotating shaft 8 to rise, drive the stirring blade 9 to push the THF residual liquid upward, and further enhance the purification effect.

[0029] As Figures 1 to 5As shown, a return spring 19 is sleeved on the outer side of the bottom end of the rotating shaft 8. One end of the return spring 19 is fixedly connected to the bottom end of the mounting pipe 13, and the other end of the return spring 19 is fixedly connected to the outer wall of the rotating shaft 8.

[0030] When the rotating shaft 8 rotates, the arc-shaped triangular plate 17 below the mounting plate 16 at the top of the rotating shaft 8 will squeeze the extrusion column 18, which can drive the rotating shaft 8 to rise. At this time, the return spring 19 is in a compressed state. When the arc-shaped triangular plate 17 rotates to be not squeezed by the extrusion column 18, under the pushing action of the return spring 19 on the rotating shaft 8, the rotating shaft 8 will be driven to descend, which can drive the stirring blade 9 to reciprocate up and down, and can stir the THF residual liquid on the tray 3 up and down, further improving the purification effect.

[0031] As Figures 1 to 5 shown, the top of the overflow weir plate 4 is higher than the stirring blade 9.

[0032] For the stirring blade 9 to fully stir the THF residual liquid on the tray 3.

[0033] The utility model provides a distillation column for purifying and recycling THF residual liquid, and the specific working principle is as follows:

[0034] When the device is in use, the THF residual liquid is transported into the distillation column body 1 through the liquid inlet pipe 2. The THF residual liquid will be transported to the topmost tray 3. When the THF residual liquid exceeds the overflow weir plate 4, the THF residual liquid will descend to the next-layer tray 3 through the first downcomer 6 and the second downcomer 11. The THF residual liquid will fall through the first precipitation holes 7 on the first downcomer 6 and the second precipitation holes 12 on the second downcomer 11, which will increase the contact area between the THF residual liquid and the heating air and improve the purification effect of 2-methyltetrahydrofuran and 3-methyltetrahydrofuran in the THF residual liquid;

[0035] When the THF residual liquid flows horizontally through the top end of the second downcomer 11, the THF residual liquid will push the fan blade 10 at the bottom end of the rotating shaft 8, which will drive the rotating shaft 8 to rotate, and will drive the stirring blade 9 to rotate, which can stir the THF residual liquid on the tray 3, improve the contact effect between the THF residual liquid and the heating air, and improve the purification effect. Through the limiting of the limiting block 15 on the rotating shaft 8 to the limiting groove 14 on the mounting pipe 13, the mounting pipe 13 will be driven to rotate synchronously. When the rotating shaft 8 rotates, the arc-shaped triangular plate 17 below the mounting plate 16 at the top of the rotating shaft 8 will squeeze the extrusion column 18, which can drive the rotating shaft 8 to rise. At this time, the return spring 19 is in a compressed state. When the arc-shaped triangular plate 17 rotates to be not squeezed by the extrusion column 18, under the pushing action of the return spring 19 on the rotating shaft 8, the rotating shaft 8 will be driven to descend, which can drive the stirring blade 9 to reciprocate up and down, and can stir the THF residual liquid on the tray 3 up and down, further improving the purification effect.

[0036] Although embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. A distillation column for purifying and recycling THF residue liquid, comprising a distillation column body (1), a liquid inlet pipe (2) is fixedly installed in the middle of the distillation column body (1), and a tray (3) is fixedly installed equidistantly in the middle of the distillation column body (1), characterized in that: An overflow weir plate (4) is fixedly installed on the upper surface of the tray (3). A water falling area (5) is formed between the overflow weir plate (4) and the inner wall of the rectifying tower body (1). First downcomers (6) are fixedly installed on the tray (3) at equal distances and symmetrically corresponding to the water falling area (5). First water discharging holes (7) are opened at equal distances below the bottom ends of the first downcomers (6). A rotating shaft (8) is rotatably installed in the middle of the tray (3). A stirring blade (9) is fixedly installed at the top of the rotating shaft (8).

2. The rectifying column for purifying and recycling THF residue liquid according to claim 1, wherein: A fan blade (10) is fixedly installed at the bottom end of the rotating shaft (8). A second downcomer (11) is fixedly installed at the middle position of the tray (3) corresponding to the water falling area (5). Second water discharging holes (12) are opened at equal distances at the bottom end of the second downcomer (11). The fan blade (10) is arranged inside the horizontal end at the top of the second downcomer (11).

3. The distillation column for purifying and recycling THF residue according to claim 2, wherein: An installation pipe (13) is rotatably installed in the middle of the tray (3) through a sealing bearing. The rotating shaft (8) is slidably installed inside the installation pipe (13). Limiting grooves (14) are symmetrically opened on the inner wall of the installation pipe (13). Limiting blocks (15) are symmetrically fixedly installed on the outer side of the rotating shaft (8). The limiting blocks (15) are slidably connected with the limiting grooves (14).

4. A rectifying column for purifying and recycling THF residue liquid according to claim 3, characterized in that: An installation plate (16) is fixedly installed at the top of the rotating shaft (8). Arc-shaped triangular plates (17) are fixedly installed on the lower surface of the installation plate (16) in an annular array with the central axis of the installation plate (16) as the axis. An extrusion column (18) is fixedly installed at the middle position of the upper surface of the tray (3) corresponding to the arc-shaped triangular plates (17). The extrusion column (18) is in extrusion contact with the arc-shaped triangular plates (17).

5. A rectification column for purifying and recycling THF residue liquid according to claim 4, characterized in that: A return spring (19) is sleeved on the outer side of the bottom end of the rotating shaft (8). One end of the return spring (19) is fixedly connected with the bottom end of the installation pipe (13), and the other end of the return spring (19) is fixedly connected with the outer wall of the rotating shaft (8).

6. A distillation column for purifying and recycling THF residue, as claimed in claim 1, wherein: The top of the overflow weir plate (4) is set higher than the stirring blade (9).

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