CN219963973U

CN219963973U - Devolatilizer

Info

Publication number: CN219963973U
Application number: CN202320582390.2U
Authority: CN
Inventors: 薛宽荣; 程慧; 梁金奎; 柳铭轩; 谢琤; 邹强
Original assignee: Shanghai Zhiying Chemical Technology Co ltd; Zhejiang Zhiying Petrochemical Technology Co ltd
Current assignee: Shanghai Zhiying Chemical Technology Co ltd; Zhejiang Zhiying Petrochemical Technology Co ltd
Priority date: 2023-03-22
Filing date: 2023-03-22
Publication date: 2023-11-07
Anticipated expiration: 2033-03-22

Abstract

The utility model relates to the field of chemical equipment, in particular to a devolatilizer, which comprises a devolatilizing shell, wherein a devolatilizing cavity for devolatilizing a polymer material is formed in the devolatilizing shell, a feeding pipeline for conveying the polymer material into the devolatilizing cavity is connected to the devolatilizing shell, a back pressure valve is connected to the feeding pipeline, the back pressure valve is arranged on one side of the feeding pipeline close to the devolatilizing shell, and is used for enabling the pressure of the polymer material in the feeding pipeline to be constant, reducing flash evaporation in the feeding pipeline, relieving the problem of pipeline blockage, reducing pipeline vibration and improving the stability of the device and the quality of products.

Description

Devolatilizer

Technical Field

The utility model relates to the field of chemical equipment, in particular to a devolatilizer.

Background

PMMA, also called polymethyl methacrylate, is a high molecular polymer, and is a glass substitute material which is commonly used. Polymerization is a common chemical process, and after the polymerization reaction reaches a certain conversion rate, it is very difficult to continue to convert the monomer, and the unconverted monomer is removed from the polymer, so that a purer polymer is obtained. The common devolatilization method is a heating flash evaporation method, and in the working process of a common flash evaporation devolatilizer, a polymer can be subjected to flash evaporation phenomenon in a conveying pipeline, so that the pipeline for conveying materials is subjected to vibration blockage, and the product performance and the equipment stability are affected.

Disclosure of Invention

The utility model provides a devolatilizer for relieving the problem of pipeline blockage and vibration caused by flash evaporation of polymer materials in a pipeline.

The devolatilizer provided by the utility model adopts the following technical scheme:

the devolatilizer comprises a devolatilization shell, a devolatilization cavity for devolatilizing the polymer material is formed in the devolatilization shell, a feeding pipeline for conveying the polymer material into the devolatilization cavity is connected to the devolatilization shell, a back pressure valve is connected to the feeding pipeline, and the back pressure valve is close to one side of the devolatilization shell.

Through adopting above-mentioned technical scheme, set up the backpressure valve on the charge-in pipeline who carries the material, make the material pressure in the charge-in pipeline keep invariable, reduce the flash distillation in the charge-in pipeline to alleviate the jam condition in the charge-in pipeline, reduce pipeline vibration, guarantee polymer devolatilization effect and equipment stability, backpressure valve is close to and devolatilizes shell one side setting in addition, makes the polymer material get into and devolatilizes in the shell from back pressure valve output back.

Further preferably, the devolatilizer further comprises a preheating device for heating the polymer material before being conveyed into the devolatilizing cavity, the preheating device comprises a preheating shell connected between the devolatilizing shell and the feeding pipeline, a heat exchange space is formed in the preheating shell, a heat exchange pipe is arranged in the heat exchange space and fixedly connected with the preheating shell, one end of the heat exchange pipe is communicated with the feeding pipeline, the other end of the heat exchange pipe is communicated with the devolatilizing cavity, and an oil inlet pipe capable of conveying heat exchange oil into the heat exchange space and an oil outlet pipe for discharging the heat exchange oil in the heat exchange space are connected to the preheating shell.

Through adopting above-mentioned technical scheme, because the polymer material carries in-process in the feed line, the temperature of polymer material can reduce, and the flash distillation can take place after the polymer material exports from the backpressure valve, the temperature of polymer material also can reduce this moment, the temperature reduces also can reduce the monomer desorption rate in the polymer material, before the polymer material in the feed line gets into the devolatilization chamber, the polymer material is sent into the heat exchange tube earlier through feed line and backpressure valve in carrying out heat transfer intensification, carry out heat transfer intensification through the polymer material in the heat exchange tube, ensure the monomer desorption rate, in addition the polymer material enters into the heat exchange tube through backpressure valve after, flash distillation can take place in the heat exchange tube also, carry out heat transfer intensification through the heat transfer oil and also in order to reduce the polymer material temperature reduction under the fuse-element state that causes because of the flash distillation.

It is further preferred that the devolatilization shell is fixedly connected or integrally formed with the preheating shell.

Through adopting above-mentioned technical scheme, devolatilization shell and preheat shell direct fixed connection or integrated into one piece, make the polymeric material through the heat exchange tube directly enter into the devolatilization intracavity, need not set up the pipeline and carry the material in the preheating shell to the devolatilization intracavity, eliminate the material and take place the flash distillation in the pipeline between devolatilization shell and preheating shell and devolatilize and cause the condition of jam.

It is further preferable that the roughness of the inner wall of the heat exchange tube and the inner wall of the devolatilization casing is Ra0.25 or Ra0.4 or Ra0.8.

Through adopting above-mentioned technical scheme, because polymer viscosity is high, the adhesion is on heat exchange tube inner wall or devolatilization shell inner wall easily after the flash distillation, and the polymer material is mainly in the heat exchange tube and devolatilization intracavity carries out the flash distillation and devolatilizes, carry out polishing treatment to heat exchange tube inner wall and devolatilization shell inner wall, make the inner wall roughness after polishing reach Ra0.25 or Ra0.4 or Ra0.8, thereby can reduce polymer adhesion wall built-up time, improve the monomer and take off the rate, reduce the product interior monomer content, the polymer material still can appear the yellow material black material easily on the inner wall adhesion time is longer, influence the quality of product.

It is further preferable that the heat exchange tubes are provided with a plurality of distribution cavities, the preheating shell is internally provided with distribution cavities, the feeding pipelines are communicated with the distribution cavities, one side, far away from the feeding pipelines, of the distribution cavities is communicated with through holes with the same quantity as the heat exchange tubes, and the heat exchange tubes are communicated with the through holes one by one.

Through adopting above-mentioned technical scheme, set up a plurality of heat exchange tubes, through distribution chamber and through-hole, distribute the polymer material in the feed line to a plurality of heat exchange tubes in again and exchange heat, can increase polymer material heat transfer area, the polymer material forms the strip in the heat exchange tube in addition, improves the heat transfer effect of heat transfer, ensures the monomer desorption rate.

It is further preferable that a baffle plate for guiding heat exchange oil is arranged in the heat exchange space, and the baffle plate is fixedly connected with the preheating shell and the heat exchange tube.

Through adopting above-mentioned technical scheme, the baffle carries out the water conservancy diversion to the heat transfer oil, makes the heat transfer oil flow in the heat transfer space, improves heat exchange efficiency to the baffle can play the supporting role to the heat transfer pipe.

It is further preferable that the devolatilization cavity is communicated and arranged in the devolatilization shell, a flange opening is connected at one side opening of the devolatilization cavity, a preheating shell is connected at one side opening of the devolatilization cavity away from the flange opening, and at least one gas phase outlet is arranged on the devolatilization shell.

Through adopting above-mentioned technical scheme, the melt polymerization material after devolatilizing in the devolatilization intracavity is discharged through the flange mouth, and other devices such as holding vessel etc. can be connected to the flange mouth, and the melt polymerization material after devolatilization can directly enter into the holding vessel through the flange mouth and preserve, and the gaseous phase monomer that devolatilizes then is discharged through the gaseous phase export, separates melt polymerization material and gaseous phase monomer, reduces the monomer content of melt polymerization material, ensures the quality of product.

Further preferably, the devolatilization cavity is sequentially divided into a semi-elliptical first cavity, a cylindrical second cavity and a conical third cavity along the through opening direction, wherein the first cavity is positioned on one side close to the preheating shell, and the radius of the cross section of the third cavity on one side far away from the second cavity is smaller than that of the cross section of the third cavity on one side close to the second cavity.

Through adopting above-mentioned technical scheme, first cavity is semi oval form, reduce gaseous monomer and polymer material gathering wall built-up in top dead angle department, the second cavity is cylindricly, for whole oval form's the cavity that takes off, cylindric second cavity can ensure sufficient space that takes off, the third cavity is the toper form, make the polymer material of wall built-up in the third space can follow and take off the shell inner wall and move down, thereby discharge smoothly from the flange mouth, reduce the stay time of melt polymer material in taking off the cavity, reduce the production of yellow material black material.

It is further preferred that the angle of inclination of the tapered generatrix of the third cavity is the same as the angle of repose of the polymer material.

Through adopting above-mentioned technical scheme, the inclination of toper generating line is the same with the angle of repose of polymer material, makes the smooth and easy downshift of polymer material discharge, reduces the wall built-up time.

Further preferably, the devolatilizing shell is fixedly provided with an observation device, and the observation device comprises a sight lamp for illuminating the devolatilizing cavity and a sight glass for facilitating manual observation of the devolatilizing cavity.

Through adopting above-mentioned technical scheme, set up the observation device and be convenient for artifical the observation and take off the condition of taking off and taking off the intracavity and the wall built-up condition of polymer material, when polymer material stopped and take off the intracavity more, when making the material liquid level about to reach the gaseous phase export, but manual control feeding pipeline and closed back pressure valve to stop the case and preheat the shell and take off and continue the feeding in the shell, thereby avoid the polymer material to take off the intracavity gathering and follow gaseous phase export and flow.

In summary, the present utility model includes at least one of the following beneficial technical effects:

1. in the utility model, the back pressure valve is arranged to ensure that the pressure of the polymer material in the feeding pipeline is constant, the flash evaporation in the feeding pipeline is reduced, the problem of pipeline blockage is relieved, the vibration of the pipeline can be reduced, and the stability of the device and the quality of products are improved;

2. in the further arrangement of the utility model, a preheating device is arranged, and the polymer material before being sent into the devolatilization cavity is subjected to heat exchange and temperature rise, so that the monomer stripping rate of the polymer material is ensured;

3. in the utility model, three parts of cavities are divided into the devolatilization cavity, the scraping wall of the polymer material is reduced at the dead angle of the devolatilization cavity under the condition of ensuring enough devolatilization space, and the inclined angle of a tapered bus of the third cavity is the same as the repose angle of the material, so that the polymer material can smoothly move down and be discharged through a flange opening;

4. in the further arrangement of the utility model, the observation device is convenient for manually observing the devolatilization condition and the wall-hanging condition of the polymer material in the devolatilization cavity, and prevents the melt polymer material from flowing out from the gas phase outlet.

Drawings

FIG. 1 is a schematic perspective view of a devolatilizer;

FIG. 2 is a front cross-sectional view of FIG. 1;

FIG. 3 is an enlarged schematic view of FIG. 2A;

FIG. 4 is a schematic top view of the first layer viewing device;

fig. 5 is a schematic top view of a second tier viewing device.

Reference numerals illustrate: 1. devolatilizing the shell; 11. a first cavity; 12. a second cavity; 13. a third cavity; 14. inclination angle; 15. a devolatilization chamber; 2. preheating the housing; 21. a dispensing chamber; 22. a through hole; 23. a heat exchange tube; 24. a partition plate; 25. a heat exchange space; 26. a bottom plate; 27. a shunt channel; 3. a gas phase outlet; 4. an observation device; 5. an oil pipe; 51. an oil inlet pipe; 52. an oil outlet pipe; 6. a back pressure valve; 7. a feed conduit; 8. and a flange opening.

Detailed Description

The present utility model is described in further detail below with reference to fig. 1-5.

The embodiment of the utility model discloses a devolatilizer, which is used for devolatilizing a polymer material. The utility model provides the following examples:

referring to fig. 1, the devolatilizer comprises a devolatilizer housing 1, a feeding pipe 7 and a back pressure valve 6, wherein a devolatilizer cavity 15 for devolatilizing the polymer material is formed in the devolatilizer housing 1, the feeding pipe is connected to the devolatilizer housing 1 and is communicated with the devolatilizer cavity 15, the back pressure valve 6 is connected to the feeding pipe 7, the back pressure valve 6 is located on one side of the feeding pipe 7 close to the devolatilizer housing 1, and one end of the feeding pipe 7 far away from the devolatilizer housing 1 is connected with a material pump (not shown).

Specifically, the polymer material is pumped into the devolatilization cavity 15 through the feeding pipeline 7 by the material pump, the pressure of the polymer material in the feeding pipeline 7 can be constant by setting the back pressure valve 6, the flash evaporation of the polymer material in the feeding pipeline 7 is reduced, if the polymer material is largely flash evaporated in the feeding pipeline 7, the two-phase mixture of the melt polymer material and the gas-phase monomer material in the feeding pipeline 7 is conveyed along the feeding pipeline 7 under the pressure action of the material pump, the pipeline is easy to vibrate and block, and the material flash evaporation in the feeding pipeline 7 can be reduced by setting the back pressure valve 6, the stability of the device and the quality of the product are improved, and the problem of pipeline blocking is relieved.

In other embodiments, a preheating device is disposed between the devolatilizing shell 1 and the feeding pipe 7, the preheating device is used for heating the polymer material before being conveyed into the devolatilizing cavity 15, flash evaporation can occur on the polymer material output in the feeding pipe 7, and the flash evaporation can cause temperature reduction of the melt polymer material, so as to affect the devolatilizing effect of the polymer material in the devolatilizing cavity 15.

Specifically, as shown in fig. 2 and fig. 3, the preheating device includes a preheating shell 2, a heat exchange space 25 is provided in the preheating shell 2, a heat exchange tube 23 is provided in the heat exchange space 25 and is fixedly connected with the preheating shell 2, one end of the heat exchange tube 23 is communicated with a feeding pipeline 7, the other end of the heat exchange tube 23 is communicated with a devolatilization cavity 15, an oil pipeline 5 is connected to the preheating shell 2 for circularly supplying heat exchange in the heat exchange space 25, the oil pipeline 5 includes an oil inlet pipe 51 capable of conveying heat exchange oil into the heat exchange space 25, and an oil outlet pipe 52 for discharging the heat exchange oil in the heat exchange space 25, in this embodiment, the oil outlet pipe 52 is connected to the top of the heat exchange space 25, and the oil inlet pipe 51 is connected to the bottom of the heat exchange space 25, so that the heat exchange oil flows from bottom to top and exchanges heat with the polymer material in the heat exchange tube 23.

In addition, in this embodiment, the heat exchange tubes 23 are provided with a plurality of heat exchange tubes 23, so that the polymer material in the feeding tube 7 can be distributed into the plurality of heat exchange tubes 23, a distribution cavity 21 is further formed in the preheating shell 2, the feeding tube 7 is communicated with the distribution cavity 21, a plurality of through holes 22 are communicated with one side of the distribution cavity 21 away from the feeding tube 7, the number of the through holes 22 is the same as that of the heat exchange tubes 23, and the heat exchange tubes 23 are communicated with the through holes 22 one by one.

The distribution cavity 21 and the through holes 22 have small volumes, so that the polymer material can enter the heat exchange tube 23 before a large amount of flash evaporation occurs in the distribution cavity 21 and the through holes 22, and a diversion channel 27 is further communicated between the distribution cavity 21 and the through holes 22, so that the polymer material flowing into the heat exchange tube 23 is in a strip shape.

The heat exchange efficiency of heat exchange oil and the polymer materials in the heat exchange pipes 23 is increased by arranging the heat exchange pipes 23, and the temperature drop of the melt polymer materials caused by flash evaporation is reduced, so that the monomer removal rate is ensured.

The baffle 24 is arranged in the heat exchange space 25, the baffle 24 is fixedly connected with the preheating shell 2 and the heat exchange tube 23, and the baffle 24 guides the flow of the heat exchange oil, so that the contact time of the heat exchange tube 23 and the heat exchange oil is prolonged, the heat exchange effect is guaranteed, and in addition, the bottom plate 26 is arranged at the bottom of the heat exchange space 25 and used for blocking the heat exchange space 25 and the devolatilization cavity 15, and the heat exchange oil is prevented from falling into the devolatilization cavity 15.

In order to reduce the conveying flow of the polymer material between the preheating device and the devolatilization shell 1, the devolatilization shell 1 is fixedly connected with the preheating shell 2 or integrally formed, and no additional pipeline is needed for conveying the polymer material in the heat exchange tube 23 into the devolatilization cavity 15.

The polymer materials sent out from the feeding pipeline 7 are mainly subjected to flash evaporation in the heat exchange tube 23 and the devolatilization cavity 15, and in order to reduce the wall hanging of the high-viscosity polymer materials after flash evaporation, the inner wall of the heat exchange tube 23 and the inner wall of the devolatilization shell 1 are subjected to polishing treatment, so that the roughness of the inner wall of the heat exchange tube 23 and the inner wall of the devolatilization shell 1 reaches Ra0.25, ra0.4 or Ra0.8. The polymer used in the present utility model is PMMA, i.e., polymethyl methacrylate, and in this embodiment, ra0.4 is selected as the roughness of the inner wall of the heat exchange tube 23 and the inner wall of the devolatilizing shell 1.

The devolatilization cavity 15 is vertically and thoroughly arranged in the devolatilization shell 1, a flange opening 8 is connected at the opening of the lower side of the devolatilization cavity 15 and can be used for connecting equipment such as a storage tank, the upper side opening of the devolatilization cavity 15 is connected with the preheating shell 2, and at least one gas phase outlet 3 is arranged on the devolatilization shell 1.

In this embodiment, two gas phase outlets 3 are formed on the devolatilizing shell 1, and the opening of the gas phase outlet 3 far away from the devolatilizing cavity 15 is inclined upwards, so that the devolatilized gas phase monomers are discharged upwards.

The devolatilization cavity 15 is sequentially divided into a first cavity 11, a second cavity 12 and a third cavity 13 from top to bottom, the first cavity 11 is semi-elliptical, dead angles can not appear at the top of the devolatilization cavity 15, the phenomenon that gas-phase monomers and polymer material wall built-up cannot fall off at dead angles is avoided, and after long-time wall built-up, the polymer material is easy to produce waste materials such as yellow material and black material.

The second cavity 12 has a cylindrical shape, and the volume of the cylindrical second cavity 12 is larger than that of the other devolatilization chamber 15 having an elliptical shape as a whole, so that the devolatilization space can be increased.

The third cavity 13 is in a conical shape, and the radius of the cross section of the side, away from the second cavity 12, of the third cavity 13 is smaller than the radius of the cross section of the side, close to the second cavity 12, of the third cavity 13, namely, the third cavity 13 is in a conical shape by shrinking inwards from top to bottom, so that the devolatilization shell 1 is convenient to manufacture, and the wall thickness of the shell body of the devolatilization shell 1 is the same from top to bottom, so that the devolatilization shell 1 is also in a semi-elliptic shape, a cylindrical shape and a conical shape from top to bottom.

The cone bus angle 14 of the third cavity 13 is the same as the repose angle of the polymer mass, which angle 14 is 60 in this example.

In the devolatilization process, the high-viscosity polymer material can temporarily stay in the devolatilization chamber 15, and in order to avoid the outflow of the stay polymer material from the gas phase outlet 3, an observation device 4 is arranged on the devolatilization shell 1, and the observation device 4 comprises a sight glass which illuminates the devolatilization chamber 15 and is convenient for manually observing the inside of the devolatilization chamber 15.

Specifically, as shown in fig. 4 and 5, in the present embodiment, the observation device 4 is provided with two layers in the up-down direction, the first layer of observation device 4 is provided on the semi-elliptical shell of the devolatilization shell 1, and the layer of observation device 4 is provided with two layers and has an angle of 180 ° with respect to each other; the second layer of observation means 4 is arranged on the cylindrical shell of the devolatilizing shell 1, the layer of observation means 4 being provided with three groups and being at an angle of 120 ° to each other. Any two observation devices 4 are not overlapped in the vertical direction, so that the condition of the liquid level of the polymer material and the condition of wall hanging at any position in the devolatilization cavity 15 can be observed through the arrangement of the two layers of observation devices 4. When the level of the polymer material in the devolatilization chamber 15 is about to reach the gas phase outlet 3, the back pressure valve 6 can be manually closed and the feed into the devolatilizer stopped.

The above embodiments are not intended to limit the scope of the present utility model, so: all equivalent changes in structure, shape and principle of the utility model should be covered in the scope of protection of the utility model.

Claims

1. The utility model provides a devolatilizer, includes devolatilization shell (1), the devolatilization shell (1) is interior to have offered and to take off the cavity (15) that volatilizees of polymer material, its characterized in that, be connected with on the devolatilization shell (1) be used for to carry feeding pipeline (7) of polymer material in the cavity (15) that takes off, be connected with backpressure valve (6) on feeding pipeline (7), backpressure valve (6) are located feeding pipeline (7) are close to take off shell (1) one side.

2. The devolatilizer as claimed in claim 1, further comprising a preheating device for heating the polymer material before being fed into the devolatilization chamber (15), wherein the preheating device comprises a preheating housing (2) connected between the devolatilization housing (1) and the feeding pipe (7), a heat exchanging space (25) is provided in the preheating housing (2), a heat exchanging pipe (23) is provided in the heat exchanging space (25) and the heat exchanging pipe (23) is fixedly connected with the preheating housing (2), one end of the heat exchanging pipe (23) is communicated with the feeding pipe (7), the other end is communicated with the devolatilization chamber (15), and an oil inlet pipe (51) capable of feeding heat exchanging oil into the heat exchanging space (25) and an oil outlet pipe (52) for discharging the heat exchanging oil in the heat exchanging space (25) are connected to the preheating housing (2).

3. A devolatilizer as claimed in claim 2, characterized in that the devolatilization housing (1) is fixedly connected or integrally formed with the preheating housing (2).

4. A devolatilizer as claimed in claim 2, characterized in that the roughness of the inner wall of the heat exchange tube (23) and the inner wall of the devolatilization casing (1) is ra0.25 or ra0.4 or ra0.8.

5. The devolatilizer as claimed in claim 2, characterized in that the heat exchange tubes (23) are provided with a plurality of distribution chambers (21) in the preheating shell (2), the feeding pipe (7) is communicated with the distribution chambers (21), one side of the distribution chambers (21) far away from the feeding pipe (7) is communicated with through holes (22) the same as the heat exchange tubes (23), and the heat exchange tubes (23) are communicated with the through holes (22) one by one.

6. A devolatilizer as claimed in claim 2 or 5, characterized in that a partition (24) for conducting heat is arranged in the heat exchanging space (25), said partition (24) being fixedly connected to the preheating housing (2) and the heat exchanging tube (23).

7. The devolatilizer as claimed in claim 2, characterized in that the devolatilization chamber (15) is arranged in the devolatilization housing (1) in a penetrating manner, a flange opening (8) is connected to an opening on one side of the devolatilization chamber (15), the preheating housing (2) is connected to an opening on one side of the devolatilization chamber (15) away from the flange opening (8), and at least one gas phase outlet (3) is arranged on the devolatilization housing (1).

8. The devolatilizer as claimed in claim 2, characterized in that the devolatilization chamber (15) is divided into a semi-elliptical first cavity (11), a cylindrical second cavity (12) and a conical third cavity (13) in sequence along the through opening direction, the first cavity (11) is located at the side close to the preheating shell (2), and the radius of the cross section of the third cavity (13) at the side far from the second cavity (12) is smaller than the radius of the cross section of the third cavity (13) at the side close to the second cavity (12).

9. A devolatilizer as claimed in claim 8, characterized in that the angle of inclination (14) of the conical generatrix of the third cavity (13) is the same as the angle of repose of the polymeric material.

10. A devolatilizer as claimed in claim 1, characterized in that the devolatilizer housing (1) is fixedly provided with an observation device (4), the observation device (4) comprising a viewing lamp for illuminating the devolatilization chamber (15) and a viewing mirror for facilitating manual observation of the devolatilization chamber (15).