CN219440721U - Low-moisture tetrahydrofuran purifying equipment - Google Patents

Abstract

The utility model discloses low-moisture tetrahydrofuran purifying equipment, which relates to the technical field of tetrahydrofuran and comprises a rectifying kettle, wherein a supporting seat, a liquid outlet pipe, a liquid inlet pipe, a vapor outlet pipe and a heat insulation seat are respectively and fixedly arranged on the surface of the rectifying kettle; the beneficial effects of the utility model are as follows: the rotation receiving cylinder, and the support ring receives the restriction unable rotation of three gag lever post, consequently pivoted receiving cylinder drives transmission lead screw downwardly moving, and transmission lead screw promotes support ring downwardly moving, and support ring moves brush layer downwardly moving, and the brush layer cleans the inner wall clearance of rectifying still, and the residue is got rid of, and is very convenient, and the sewage that mixes the residue at last is discharged from the drain pipe.

Description

Low-moisture tetrahydrofuran purifying equipment

Technical Field

The utility model relates to purification equipment, in particular to low-moisture tetrahydrofuran purification equipment, and belongs to the technical field of tetrahydrofuran.

Background

Tetrahydrofuran is an important organic synthetic raw material and is a solvent with excellent performance, particularly suitable for dissolving PVC, polyvinylidene chloride and butylaniline, widely used as a solvent for surface coating, anticorrosive coating, printing ink, magnetic tape and film coating, and used as a reaction solvent, and can randomly control the thickness of aluminum layer and lighten when used in an aluminum electroplating solution. The crude tetrahydrofuran needs to be purified during the production of low-moisture tetrahydrofuran.

The tetrahydrofuran purifying device disclosed by the application number CN201821222259.0 comprises a crude tetrahydrofuran waste water storage tank, a heat exchanger, a first rectifying tower, a second rectifying tower and a third rectifying tower which are sequentially connected through pipelines, wherein the crude tetrahydrofuran waste water storage tank is connected with a fusel oil storage tank through a pipeline; the top outlet of the first rectifying tower is sequentially connected with a first condenser and a first reflux tank through pipelines, the tail end of the pipeline connected with the top outlet of the first rectifying tower is divided into two branches, one branch is connected with the upper part of the first rectifying tower, and the other branch is connected with the middle upper part of the second rectifying tower. By adopting the device, the tetrahydrofuran in the fusel oil storage tank can be fully recovered by proportionally mixing the fusel oil and the wastewater in the wastewater storage tank and carrying out rectification recovery again, and the application number of the device is CN202220623915.8, which discloses a tetrahydrofuran purifying device which comprises a crude tetrahydrofuran storage tank, wherein the crude tetrahydrofuran tank is connected with a rectification kettle, a stirring shaft is arranged in the rectification kettle, a motor is arranged above the stirring shaft, a stirring rod is arranged below the stirring shaft, a heating component and a temperature detection device are arranged in the rectification kettle, a steam outlet pipe is arranged on the side surface of the rectification kettle, a filter cavity is connected with the steam outlet pipe, and a pervaporation membrane component is arranged in the filter cavity and is connected with a condensation tank. This application is sent into rectifying still with crude tetrahydrofuran, through heating crude tetrahydrofuran in rectifying still to control heating temperature makes tetrahydrofuran become the vapor phase, filters the impurity in the crude tetrahydrofuran through the pervaporation membrane module in the filter chamber, condenses in the condensing pot at last and obtains the higher tetrahydrofuran of purity, not only can improve the purity of crude tetrahydrofuran when using, and use more convenient, nimble ", but above-mentioned low moisture tetrahydrofuran purification equipment still has following defect:

1) The inner wall of the rectifying still is inconvenient to clean, a large amount of residues are adhered to the inner wall of the rectifying still after the rectification is finished, the rectification is incomplete in the subsequent rectification process due to the large amount of residues, and the use efficiency of raw materials is reduced.

Disclosure of Invention

The utility model aims to provide low-moisture tetrahydrofuran purifying equipment, which solves the problems that the prior art is inconvenient to clean the inner wall of a rectifying still, a large amount of residues are attached to the inner wall of the rectifying still after the rectification is finished, the rectification is incomplete in the subsequent rectification process due to the large amount of residues, and the use efficiency of raw materials is reduced.

In order to achieve the above purpose, the present utility model provides the following technical solutions: the utility model provides a low moisture tetrahydrofuran purification equipment, includes the rectifying still, rectifying still's surface is fixed respectively and is equipped with supporting seat, drain pipe, feed liquor pipe, play vapour pipe and thermal-insulated seat, rectifying still's inside is equipped with the clearance subassembly, the clearance subassembly includes supporting ring and drive assembly, the fixed surface that sets up at the rectifying still of supporting ring, the inner wall sliding connection of supporting ring has the transmission lead screw, the fixed clean ring that is equipped with of one end of transmission lead screw, the fixed surface of clean ring is equipped with the brush layer, the surface of transmission lead screw has a receiving vessel through lead screw nut threaded connection, three spacing hole has been seted up on clean ring's surface, and three the equal sliding connection of inner wall in spacing hole has the gag lever post.

Preferably, the surface of brush layer and the inner wall sliding connection of rectifying still, the top fixed connection of sealed bearing and holding ring is passed through to the bottom of receiving vessel, and is three the inside of rectifying still is all arranged in to gag lever post and clean ring, three the contact part of gag lever post and rectifying still is all fixed connection.

Preferably, the drive assembly comprises a first bracket, the first bracket is fixedly arranged on the surface of the rectifying still, a first motor is fixedly arranged at the top end of the first bracket, the first motor is a forward and reverse motor, a first bevel gear is fixedly arranged on a transmission shaft of the first motor, a second bevel gear is connected to one side of the first bevel gear in a meshed manner, and the inner wall of the second bevel gear is fixedly connected with the surface of the storage barrel.

Preferably, the inside of supporting seat has been seted up the conduction groove, the inside packing of conduction groove has conduction oil, the fixed a plurality of electrical heating board that is equipped with of inner wall of conduction groove, a plurality of electrical heating board is annular evenly distributed, the front of supporting seat is fixed to be equipped with the second support, the surface of second support is positive to be fixed to be equipped with the flush mounting plate of switch, the surface coating of supporting seat has the thermal-insulated lacquer, the play piping channel has been seted up on the surface of supporting seat.

Preferably, one end of the liquid outlet pipe penetrates through the supporting seat and is arranged in the liquid outlet pipe groove, a first electric valve is fixedly arranged on the surface of the liquid outlet pipe, a second electric valve is fixedly arranged on the surface of the liquid inlet pipe, a third electric valve is fixedly arranged on the surface of the vapor outlet pipe, a filter cylinder is fixedly arranged at one end of the vapor outlet pipe, an ingress pipe is fixedly arranged at one end of the filter cylinder, and a pervaporation membrane is fixedly arranged in the filter cylinder.

Preferably, the one end of introducing pipe is fixed and is equipped with the condensation tank, the fixed spiral condenser pipe that is equipped with of inner wall of condensation tank, the fixed inlet tube, outlet pipe, discharging pipe and a plurality of supporting leg that is equipped with respectively in surface of condensation tank, the one end and the water inlet end fixed connection of spiral condenser pipe of inlet tube, the one end and the water outlet end fixed connection of spiral condenser pipe of outlet pipe, the fixed surface of inlet tube is equipped with the fourth motorised valve, the fixed surface of discharging pipe is equipped with the fifth motorised valve.

Preferably, the top of thermal-insulated seat is fixed and is equipped with the second motor, the transmission shaft of second motor is fixed and is equipped with the puddler, the surface of puddler is rotated with the inner wall of thermal-insulated seat through sealed bearing and is connected, the fixed surface of puddler is equipped with a plurality of stirring leaf, the inside of rectifying still is all arranged in to puddler and a plurality of stirring leaf.

Preferably, the surface of the switch panel is provided with a first motor switch, a second motor switch, an electric heating plate switch, a first electric valve switch, a second electric valve switch, a third electric valve switch, a fourth electric valve switch and a fifth electric valve switch respectively, and the first motor, the second motor, a plurality of electric heating plates, the first electric valve, the second electric valve, the third electric valve, the fourth electric valve and the fifth electric valve are electrically connected with an external power supply through the first motor switch, the second motor switch, the electric heating plate switch, the first electric valve switch, the second electric valve switch, the third electric valve switch, the fourth electric valve switch and the fifth electric valve switch respectively.

Compared with the related art, the low-moisture tetrahydrofuran purifying device provided by the utility model has the following beneficial effects:

the rotary storage barrel is rotated, and the supporting ring is limited by the three limiting rods and cannot rotate, so that the rotary storage barrel drives the transmission screw rod to move downwards, the transmission screw rod pushes the supporting ring to move downwards, the supporting ring drives the hairbrush layer to move downwards, the hairbrush layer cleans the inner wall of the rectifying still, residues are removed, the operation is very convenient, and finally, sewage mixed with the residues is discharged from the liquid outlet pipe;

the first motor drives first helical gear to rotate, and first helical gear drives the second helical gear to rotate, and the second helical gear drives the storage barrel to rotate, finally makes supporting ring and brush layer downwardly moving, compares with the manual rotation storage barrel, and the support seat of need not the staff to climb again rotates the storage barrel, and is safer, reduces intensity of labour simultaneously, and is very convenient.

Drawings

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is an enlarged schematic view of the structure of FIG. 1A according to the present utility model;

FIG. 3 is a schematic cross-sectional view of the present utility model;

FIG. 4 is an enlarged schematic view of the structure of FIG. 3B according to the present utility model;

fig. 5 is an enlarged schematic view of the structure of fig. 3 at C according to the present utility model.

In the figure: 1. a rectifying still; 2. a support base; 3. a liquid outlet pipe; 4. a liquid inlet pipe; 5. a steam outlet pipe; 6. a heat insulation seat; 7. cleaning the assembly; 71. a support ring; 72. a transmission screw rod; 73. a cleaning ring; 74. a brush layer; 75. a storage barrel; 76. a limiting hole; 77. a limit rod; 8. a drive assembly; 81. a first bracket; 82. a first motor; 83. a first helical gear; 84. a second helical gear; 9. a heat conduction groove; 10. an electric heating plate; 11. a second bracket; 12. a switch panel; 13. a pipe outlet groove; 14. a filter cartridge; 15. an ingress pipe; 16. a condensing tank; 17. a water inlet pipe; 18. a water outlet pipe; 19. a discharge pipe; 20. support legs; 21. a second motor; 22. a stirring rod; 23. stirring the leaves; 24. a spiral condenser tube.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Examples

Referring to fig. 1-5, the utility model provides a low-moisture tetrahydrofuran purifying device, which comprises a rectifying still 1, wherein a supporting seat 2, a liquid outlet pipe 3, a liquid inlet pipe 4, a vapor outlet pipe 5 and a heat insulation seat 6 are respectively and fixedly arranged on the surface of the rectifying still 1, and a cleaning component 7 is arranged in the rectifying still 1;

the inside of the supporting seat 2 is provided with a heat conduction groove 9, the inside of the heat conduction groove 9 is filled with heat conduction oil, the inner wall of the heat conduction groove 9 is fixedly provided with a plurality of electric heating plates 10, the plurality of electric heating plates 10 are uniformly distributed in a ring shape so as to heat the heat conduction oil in the heat conduction groove 9, the front surface of the supporting seat 2 is fixedly provided with a second bracket 11, the front surface of the second bracket 11 is fixedly provided with a switch panel 12, the surface of the supporting seat 2 is coated with heat insulation paint, the heat insulation effect of the supporting seat 2 is improved, the surface of the supporting seat 2 is provided with a pipe outlet groove 13, and the arranged pipe outlet groove 13 is convenient for leakage of a liquid outlet pipe 3;

one end of the liquid outlet pipe 3 penetrates through the supporting seat 2 and is arranged in the liquid outlet pipe groove 13, a first electric valve is fixedly arranged on the surface of the liquid outlet pipe 3, a second electric valve is fixedly arranged on the surface of the liquid inlet pipe 4, a third electric valve is fixedly arranged on the surface of the vapor outlet pipe 5, a filter cylinder 14 is fixedly arranged at one end of the vapor outlet pipe 5, an ingress pipe 15 is fixedly arranged at one end of the filter cylinder 14, a pervaporation membrane is fixedly arranged in the filter cylinder 14, the boiling point of water is much higher than that of tetrahydrofuran, the pervaporation membrane allows tetrahydrofuran vapor to pass through and blocks vapor evaporated when the boiling point of the water is lower, so that a vapor pressure difference exists at two sides of the pervaporation membrane, the vapor pressure difference is larger, and further negative pressure can be caused by suction of a vacuum pump at the downstream of the pervaporation membrane, so that the vapor pressure difference at two sides of the membrane is improved;

a condensing tank 16 is fixedly arranged at one end of the ingress pipe 15, a spiral condensing pipe 24 is fixedly arranged on the inner wall of the condensing tank 16, a water inlet pipe 17, a water outlet pipe 18, a discharge pipe 19 and a plurality of supporting legs 20 are fixedly arranged on the surface of the condensing tank 16 respectively, one end of the water inlet pipe 17 is fixedly connected with the water inlet end of the spiral condensing pipe 24, separated tetrahydrofuran steam is cooled through the spiral condensing pipe 24 containing cold water, liquefaction of the tetrahydrofuran steam can enable one side of a pervaporation membrane to maintain low pressure, the separation effect of the pervaporation membrane is favorably maintained, one end of the water outlet pipe 18 is fixedly connected with the water outlet end of the spiral condensing pipe 24, a fourth electric valve is fixedly arranged on the surface of the water inlet pipe 17, and a fifth electric valve is fixedly arranged on the surface of the discharge pipe 19;

the top end of the heat insulation seat 6 is fixedly provided with a second motor 21, a transmission shaft of the second motor 21 is fixedly provided with a stirring rod 22, the surface of the stirring rod 22 is rotationally connected with the inner wall of the heat insulation seat 6 through a sealing bearing, the surface of the stirring rod 22 is fixedly provided with a plurality of stirring blades 23, the stirring rod 22 and the stirring blades 23 are all arranged in the rectifying still 1, the second motor 21 is started through a second motor switch, the second motor 21 drives the stirring rod 22 to rotate, the stirring rod 22 drives the stirring blades 23 to rotate, and crude tetrahydrofuran in the rectifying still 1 is stirred to be heated uniformly;

the surface of the switch panel 12 is respectively provided with a second motor switch, an electric heating plate switch, a first electric valve switch, a second electric valve switch, a third electric valve switch with an electric valve, a fourth electric valve switch and a fifth electric valve switch, and the second motor 21, the plurality of electric heating plates 10, the first electric valve, the second electric valve, the third electric valve with an electric valve, the fourth electric valve and the fifth electric valve are respectively electrically connected with an external power supply through the second motor switch, the electric heating plate switch, the first electric valve switch, the second electric valve switch, the third electric valve switch with an electric valve, the fourth electric valve switch and the fifth electric valve switch;

referring to fig. 1-5, the utility model provides a low-moisture tetrahydrofuran purifying device, which further comprises a cleaning assembly 7, wherein the cleaning assembly 7 comprises a supporting ring 71 and a driving assembly 8, the supporting ring 71 is fixedly arranged on the surface of a rectifying still 1, a transmission screw rod 72 is slidably connected to the inner wall of the supporting ring 71, a cleaning ring 73 is fixedly arranged at one end of the transmission screw rod 72, a brush layer 74 is fixedly arranged on the surface of the cleaning ring 73, a storage barrel 75 is connected to the surface of the transmission screw rod 72 through screw and nut threads, three limiting holes 76 are formed in the surface of the cleaning ring 73, and limiting rods 77 are slidably connected to the inner walls of the three limiting holes 76;

the surface of the brush layer 74 is in sliding connection with the inner wall of the rectifying still 1, the bottom end of the accommodating cylinder 75 is fixedly connected with the top end of the supporting ring 71 through a sealing bearing, three limiting rods 77 and the cleaning ring 73 are all arranged in the rectifying still 1, and the three limiting rods 77 are fixedly connected with the contact part of the rectifying still 1;

specifically, as shown in fig. 1, 2, 3, 4 and 5, the support ring 71 is limited by three limiting rods 77, the storage barrel 75 is rotated, the rotating storage barrel 75 drives the transmission screw 72 to move downwards, the transmission screw 72 pushes the support ring 71 to move downwards, the support ring 71 drives the brush layer 74 to move downwards, and the brush layer 74 cleans the inner wall of the rectifying still 1 to remove residues, so that the device is very convenient.

Examples

The driving assembly 8 comprises a first bracket 81, the first bracket 81 is fixedly arranged on the surface of the rectifying still 1, a first motor 82 is fixedly arranged at the top end of the first bracket 81, the first motor 82 is a forward and reverse motor, a first bevel gear 83 is fixedly arranged on a transmission shaft of the first motor 82, a second bevel gear 84 is connected to one side of the first bevel gear 83 in a meshed manner, and the inner wall of the second bevel gear 84 is fixedly connected with the surface of the receiving cylinder 75;

the surface of the switch panel 12 is provided with a first motor switch, and the first motor 82 is electrically connected with an external power supply through the first motor switch;

specifically, as shown in fig. 1, 2, 3 and 4, the first motor 82 is started through the first motor switch, the first motor 82 drives the first bevel gear 83 to rotate, the first bevel gear 83 drives the second bevel gear 84 to rotate, the second bevel gear 84 drives the storage barrel 75 to rotate, and finally the supporting ring 71 and the brush layer 74 are driven to move downwards.

Working principle: when the low-moisture tetrahydrofuran purifying device is particularly used, firstly, when the rectifying still 1 after rectification needs to be cleaned, the second electric valve is opened through the second electric valve switch, then clean water mixed with cleaning liquid is poured into the liquid inlet pipe 4 to submerge the supporting ring 71 and the brush layer 74, then the first motor 82 is started through the first motor switch, the first motor 82 drives the first bevel gear 83 to rotate, the first bevel gear 83 drives the second bevel gear 84 to rotate, the second bevel gear 84 drives the accommodating cylinder 75 to rotate, the supporting ring 71 is limited by the three limiting rods 77 and can not rotate, the rotating accommodating cylinder 75 drives the transmission screw 72 to move downwards, the transmission screw 72 drives the supporting ring 71 to move downwards, the supporting ring 71 drives the brush layer 74 to move downwards, the brush layer 74 cleans the inner wall of the rectifying still 1 to remove residues, and the residues are quite convenient, compared with manual rotation of the accommodating cylinder 75, the accommodating cylinder 75 is driven to rotate by the driving component 8, a worker does not need to climb up the supporting seat 2 and then rotate the accommodating cylinder 75, the labor intensity is reduced, the first electric valve is opened by the first electric valve switch after cleaning, sewage mixed with residues is discharged from the liquid outlet pipe 3, when low-moisture tetrahydrofuran is required to be purified from the crude tetrahydrofuran, the electric heating plates 10 are started by the electric heating plate switch, the electric heating plates 10 heat conduction oil, further heat the crude tetrahydrofuran in the rectifying still 1, when the crude tetrahydrofuran is heated to a proper temperature, tetrahydrofuran in the crude tetrahydrofuran is vaporized, high pressure is formed in the rectifying still 1, the third electric valve is opened by the third electric valve switch, tetrahydrofuran steam is pressed into the filtering cylinder 14 by the steam outlet pipe 5, a permeable vaporization membrane is fixedly arranged in the filtering cylinder 14, the boiling point of water is much higher than that of tetrahydrofuran, the pervaporation membrane allows tetrahydrofuran steam to pass through, steam evaporated when the boiling point of water is lower than that of the tetrahydrofuran, meanwhile, steam pressure difference exists at two sides of the pervaporation membrane, separation of the tetrahydrofuran steam is quickened, further negative pressure can be caused by sucking by a vacuum pump at the downstream of the pervaporation membrane, thereby the steam pressure difference at two sides of the membrane is improved, cold water circulation is formed by a peripheral water pump, a water inlet pipe 17, a spiral condensing pipe 24, a water outlet pipe 18 and a peripheral water storage tank, the separated tetrahydrofuran steam is cooled by the spiral condensing pipe 24 containing cold water, liquefaction of the tetrahydrofuran steam can enable one side of the pervaporation membrane to maintain low pressure, and the separation effect of the pervaporation membrane is favorably maintained.

Although embodiments of the present utility model have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims (8)

1. The utility model provides a low moisture tetrahydrofuran purification equipment, includes rectifying still (1), its characterized in that, the fixed supporting seat (2), drain pipe (3), feed liquor pipe (4), play vapour pipe (5) and thermal-insulated seat (6) that are equipped with respectively in surface of rectifying still (1), the inside of rectifying still (1) is equipped with clearance subassembly (7), clearance subassembly (7) include supporting ring (71) and drive assembly (8), the fixed surface that sets up at rectifying still (1) of supporting ring (71), the inner wall sliding connection of supporting ring (71) has transmission lead screw (72), the one end of transmission lead screw (72) is fixed to be equipped with clean ring (73), the fixed surface of clean ring (73) is equipped with brush layer (74), the surface of transmission lead screw (72) is equipped with receiver (75) through lead screw nut threaded connection, three spacing hole (76) are seted up on the surface of clean ring (73) the equal sliding connection of inner wall of spacing hole (76) has gag lever post (77).

2. The low-moisture tetrahydrofuran purifying apparatus of claim 1, wherein: the surface of brush layer (74) and the inner wall sliding connection of rectifying still (1), the top fixed connection of bottom of receiving vessel (75) and supporting ring (71) is passed through sealed bearing, and is three gag lever post (77) and cleaning ring (73) are all arranged in the inside of rectifying still (1), three gag lever post (77) all fixed connection with the contact part of rectifying still (1).

3. The low-moisture tetrahydrofuran purifying apparatus of claim 1, wherein: the driving assembly (8) comprises a first bracket (81), the first bracket (81) is fixedly arranged on the surface of the rectifying still (1), a first motor (82) is fixedly arranged at the top end of the first bracket (81), the first motor (82) is a forward and reverse motor, a first bevel gear (83) is fixedly arranged on a transmission shaft of the first motor (82), a second bevel gear (84) is connected to one side of the first bevel gear (83) in a meshed mode, and the inner wall of the second bevel gear (84) is fixedly connected with the surface of the accommodating barrel (75).

4. A low moisture tetrahydrofuran purifying apparatus according to claim 3, wherein: the inside of supporting seat (2) has been seted up heat conduction groove (9), the inside packing of heat conduction groove (9) has heat conduction oil, the fixed a plurality of electrical heating board (10) that is equipped with of inner wall of heat conduction groove (9), a plurality of electrical heating board (10) are annular evenly distributed, the front of supporting seat (2) is fixed to be equipped with second support (11), the surface of second support (11) is positive to be fixed to be equipped with flush mounting plate of switch (12), the surface coating of supporting seat (2) has thermal-insulated lacquer, go out piping connection (13) have been seted up on the surface of supporting seat (2).

5. The low-moisture tetrahydrofuran purifying apparatus of claim 4, wherein: one end of drain pipe (3) runs through supporting seat (2) and is put in the inside of play piping groove (13), the fixed surface of drain pipe (3) is equipped with first motorised valve, the fixed surface of feed liquor pipe (4) is equipped with the second motorised valve, the fixed surface of play vapour pipe (5) is equipped with the third motorised valve, the fixed cartridge filter (14) that is equipped with of one end of play vapour pipe (5), the fixed ingress pipe (15) that is equipped with of one end of cartridge filter (14), the fixed pervaporation membrane that is equipped with in inside of cartridge filter (14).

6. The low-moisture tetrahydrofuran purifying apparatus of claim 5, wherein: the utility model discloses a condenser, including condensation jar, inlet tube (17), outlet pipe (18), discharging pipe (19) and a plurality of supporting leg (20), the fixed condensation jar (16) that is equipped with of one end of ingress pipe (15), the fixed spiral condenser pipe (24) that is equipped with of inner wall of condensation jar (16), the fixed inlet tube (17), outlet pipe (18), discharging pipe (19) and a plurality of supporting leg (20) are equipped with respectively on the surface of condensation jar (16), the one end of inlet tube (17) and the inlet end fixed connection of spiral condenser pipe (24), the one end of outlet pipe (18) and the play water end fixed connection of spiral condenser pipe (24), the fixed surface of inlet tube (17) is equipped with fourth motorised valve, the fixed surface of discharging pipe (19) is equipped with fifth motorised valve.

7. The low-moisture tetrahydrofuran purifying apparatus of claim 6, wherein: the utility model discloses a rectifying still (1), including heat-insulating seat (6), stirring rod (22), sealing bearing, stirring rod (22) and inner wall rotation connection of heat-insulating seat (6), the fixed second motor (21) that is equipped with in top of heat-insulating seat (6), the transmission shaft of second motor (21) is fixed, the surface of stirring rod (22) is rotated with the inner wall of heat-insulating seat (6) through sealing bearing, the fixed surface of stirring rod (22) is equipped with a plurality of stirring leaf (23), the inside of rectifying still (1) is all arranged in stirring rod (22) and a plurality of stirring leaf (23).

8. The low-moisture tetrahydrofuran purifying apparatus of claim 7, wherein: the surface of the switch panel (12) is respectively provided with a first motor switch, a second motor switch, an electric heating plate switch, a first electric valve switch, a second electric valve switch, a third electric valve switch, a fourth electric valve switch and a fifth electric valve switch, and the first motor (82), the second motor (21), a plurality of electric heating plates (10), the first electric valve, the second electric valve, the third electric valve, the fourth electric valve and the fifth electric valve are respectively electrically connected with an external power supply through the first motor switch, the second motor switch, the electric heating plate switch, the first electric valve switch, the second electric valve switch, the third electric valve switch, the fourth electric valve switch and the fifth electric valve switch.