JP3722138B2 - Continuous polycondensation apparatus and continuous polycondensation method - Google Patents

Description

The present invention relates to a continuous polycondensation apparatus and a continuous polycondensation method suitable for continuous production of polyester polymers such as polyethylene terephthalate and polybutylene terephthalate.

  Conventionally, as a method for producing a polycondensation polymer such as polyethylene terephthalate, terephthalic acid and ethylene glycol as raw materials are put into a mixing tank at an appropriate ratio for esterification, and sent to an esterification reaction tank by a pump. In this esterification step, 2 to 3 stirring tanks with stirring blades are arranged in series, and water produced as a side reaction product is separated by a distillation tower. Next, a plurality of vertical stirring tanks and horizontal stirring tanks are installed as a prepolymerization process, and a horizontal stirring tank is installed as a final polymerization process. In these polymerization process tanks, a condenser is installed to remove ethylene glycol as a by-product, and the apparatus is operated in a reduced pressure atmosphere. In the conventional polyester manufacturing process, the number of reaction tanks is 4 to 6 cans, each reaction tank is equipped with a stirring blade and its power source, and a distillation tower and condenser for separating and removing byproducts are installed. ing. Furthermore, since the polymerization process is operated in a reduced-pressure atmosphere, the vacuum means must be operated by another apparatus, and the operation of the production apparatus requires high maintenance costs and apparatus costs.

Japanese Patent Laid-Open No. 7-207090

  The problem of the present invention is an improvement over known methods for the production of high molecular weight polyesters, which improves the overall efficiency of the apparatus and operates economically with energy savings in factory equipment.

  It is an object of the present invention to provide a continuous polycondensation apparatus and a continuous polycondensation method that improve the above-described prior art and efficiently react a high-quality polymer with a minimum amount of energy with a minimum required reactor configuration. is there.

The above-mentioned object has an inlet nozzle and an outlet nozzle for the liquid to be treated at the lower end of the substantially horizontal cylindrical container main body in the longitudinal direction and a lower end of the other end, respectively, and an outlet nozzle for volatiles at the upper part of the main body. In a continuous polycondensation apparatus provided with a stirring rotor that rotates in the longitudinal direction inside and close to the inside of the main body, the stirring rotor does not have a rotating shaft at the center of the stirring rotor and is a rotor that is connected to a plurality of strength members A support member is provided at both ends, and is composed of stirring blade blocks in a low viscosity region, a medium viscosity region, and a high viscosity region corresponding to the viscosity of the treatment liquid formed between the support members. A low-viscosity agitation block comprising a bucket part provided in a low-viscosity area on the inlet nozzle side of the processing liquid, and a thin disk and a hollow disk into which the processing liquid is poured from the bucket part; During ~ A hollow disk is arranged on both sides, a plurality of hollow thin plates with the same outer diameter are installed in it, and a plurality of oyster plates that penetrate these members are installed radially on the outer periphery. A plurality of discs having a hollow portion in the wheel mold provided in the high viscosity region on the exit nozzle side of the viscosity stirring block and the liquid to be treated are installed at appropriate intervals, and oyster plates are alternately placed in the front and back on the outer peripheral portion of the disc. A continuous polycondensation device consisting of an installed high-viscosity stirring block and having a oyster member that pushes the processing liquid on the side wall of the main body to the outer periphery by rotation of the stirring rotor on the side of the main body of the rotor support member on the volatiles outlet nozzle side Using the continuous polycondensation device, a prepolymer having a low degree of polymerization is continuously supplied from the inlet nozzle of the liquid to be processed, and the processing liquid is stirred by rotating the stirring rotor while forming a liquid film by each stirring block. Thus, the surface of the treatment liquid is renewed to evaporate the volatiles and move toward the outlet nozzle of the liquid to be treated to increase the degree of polymerization and polycondensate the polyester polymer to form a continuous polycondensation method. Is achieved.

According to the present invention, the treatment liquid can be handled from the treatment liquid viscosity of several hundred Pas in the final polymerization process among the esterification process, the pre-polymerization process, and the final polymerization process in the continuous production of the polyester polymer. Since the viscosity of the Pas treatment solution can be increased, the efficiency of the entire apparatus is improved, and it can be operated economically by saving energy in factory equipment.

  With the minimum required reactor configuration, the objective of efficiently reacting a high-quality polymer with the least energy is to use a continuous production facility for polyester with three reactors: esterification process, pre-polymerization process, and final polymerization process. It was realized by doing.

  FIG. 1 shows an embodiment of the present invention. FIG. 1 is an apparatus configuration diagram of a continuous production process of polyethylene terephthalate according to the present invention. As an industrial polyester production method, the direct esterification method is economically very advantageous, and recently, the direct esterification method has been widely adopted. In the figure, 31 is a raw material adjustment tank in which TPA (terephthalic acid) and EG (ethylene glycol), which are polyethylene terephthalate raw materials, are mixed and stirred at a predetermined ratio. In the manufacturing process, additives such as a polymerization reaction catalyst, a stabilizer, and a color adjusting agent may be added at this stage. Examples of the polymerization reaction catalyst include metal compounds such as antimony, titanium, germanium, tin, and zinc. Not only the reaction rate varies depending on the type and combination of the catalyst used, but also the hue and thermal stability of the resulting polyester. It is well known that it is different. Furthermore, since these reactions are carried out at high temperatures for a long time due to the presence of a catalyst, various side reactions are involved, and the polymer is colored yellow, or the content of diethylene glycol (DEG) and the terminal carboxyl group concentration are more than appropriate values. The physical properties such as the melting point and strength of the polyester are lowered. In order to improve such problems, new catalysts have been developed. However, antimony compounds that are most commonly used industrially, particularly antimony triacid, are superior in price and performance. However, coloring of the produced polyester polymer is inevitable even when this catalyst is used. For this reason, a phosphorus stabilizer (for example, trimethyl phosphate, triphenyl phosphate) is used in combination as a stabilizer. Also, in another manufacturing process, the quality is stabilized by devising the input position of the polymerization catalyst and stabilizer. In a normal process, it is preferred to use 200 to 400 ppm of catalyst and 50 to 200 ppm of stabilizer.

  The raw material adjusted as described above goes through a supply line 32 for supplying the raw material to the esterification reaction tank 33. The outer periphery of the esterification reaction tank (first reactor) 33 has a jacket structure (not shown) in order to keep the treatment liquid at the reaction temperature. An exchanger 34 is installed to heat the treatment liquid with an external heat source, and the reaction proceeds while circulating the liquid inside by natural circulation. Here, the most desirable reactor type is preferably a Calandria type in which the processing liquid in the reactor is naturally circulated by utilizing the evaporation effect of a by-product generated by the self-reaction of the esterification reaction. Since this type of reactor does not require an external stirring power source, the configuration of the apparatus is simple, and a shaft sealing device for the stirring shaft is not required, and the production cost of the reactor is reduced. As an example of such a reactor, an apparatus as shown in FIG. 2 is desirable.

  FIG. 2 shows an embodiment of this apparatus. The liquid 52 to be treated flows from an inlet 53 provided in the lower part of the vertical evaporator 1, and flows and heats in a plurality of heat transfer tubes (not shown) of the multi-tube heat exchanger 4, thereby natural convection. It rises by. Here, a part of the low boiling point component of the liquid 52 to be treated is evaporated and discharged from the vapor pipe 55 to the outside of the apparatus. The remaining liquid to be treated 52 flows down by natural convection between the inner wall of the evaporator 51 and the outer wall of the shell of the multitubular heat exchanger 54, and has a cylindrical shape provided at the bottom of the shell of the multitubular heat exchanger 4. It flows into the run-up space 56. Here, the flow of the processing liquid is rectified with less turbulence, and the average flow velocity in the tube of the multi-tube heat exchanger 54 is increased more than the average flow velocity flowing down by natural convection, so that the velocity is more uniform. It flows into a plurality of heat transfer tubes in a distribution, and each liquid to be treated is heated again uniformly and repeats circulation by natural convection. In this process, the low boiling point components gradually evaporate, and the liquid 59 to be treated which has been concentrated after an appropriate convection time is led out of the system through the outlet 60. Here, in order to generate a smooth accelerated flow, the flow passage area of the cylindrical run-up space is designed to be larger than the total flow passage area of the heat transfer tubes, and further, the inner wall of the evaporator 51 and the multitubular heat exchange are designed. This is achieved by making the flow area of the double pipe portion formed between the outer wall of the shell of the vessel 54 larger than the flow area of the running space. In addition, 57 shows the inlet of a heat medium, 58 shows the outlet of a heat medium, and the circumference | surroundings of the evaporator 51 are enclosed by the heat insulating material or the jacket (not shown).

  Therefore, in the evaporator according to the present embodiment, since the velocity distribution is uniform along the axial direction of the heat exchanger, the liquid to be treated can perform more uniform evaporation or reaction, and better product quality can be achieved with a short residence time. There is an effect that can be obtained. Even when the liquid 52 to be processed is a mixture of solid particles and liquid (hereinafter referred to as slurry), the liquid 52 to be naturally circulated is a cylindrical running space 56 provided in the lower part of the shell of the multi-tubular heat exchanger 54. However, since the particles rise more smoothly along the conical member 62, the solid particles do not settle at the bottom. When the liquid to be treated is a slurry, precipitation of solid particles contained in the slurry can be prevented by providing a conical member for raising the liquid to be treated internally circulated at the bottom of the evaporator. Here, the conical member may have a certain curvature. Therefore, the evaporator according to the present embodiment has an effect that a suitable evaporator can be provided by natural circulation of the slurry, and a reliable and good quality product can be obtained. However, in the present invention, this apparatus is not limited, and a reactor having a stirring blade may be used for process reasons.

  In the first reactor, water produced by the reaction becomes water vapor, and forms vapor phase portion 5 with vaporized EG vapor. At this time, as recommended reaction conditions, the temperature is 240 ° C. to 280 ° C., and pressurized conditions are desirable. The gas in the gas phase section 5 is separated into water and EG by a rectification tower (not shown) provided on the upstream side thereof, the water is removed from the system, and the EG is returned to the system again. As an advantage of the present invention, the number of rectification towers can be reduced to one by treating the esterification process in one reactor, and not only the production cost of the rectification tower but also the number of pipes and valves can be controlled. The number of devices can be reduced, resulting in a significant reduction in equipment costs. The processing liquid that has passed a predetermined reaction time in the esterification reaction tank 33 reaches a predetermined esterification rate, and is supplied to an initial polymerization tank (second reactor) 37 through a communication pipe 36. At this time, the treatment liquid is heated to a predetermined reaction temperature by the heat exchanger 38 and undergoes a polycondensation reaction to increase the degree of polymerization. At this time, the reaction conditions are 270 to 290 degrees, the pressure is 266 to 133 Pa, and the polymerization degree is about 20 to 40.

  Although the initial polymerization tank shown in the present embodiment is described using a reactor having no stirring blade, this reactor is not limited. However, in the initial polymerization stage, the reaction is a stage in which the polymerization reaction rate is a rule of the reaction rate, and the reaction proceeds smoothly if a sufficient amount of heat necessary for the reaction is supplied. From this point of view, the treatment liquid does not need to be subjected to unnecessary stirring action by the stirring blade, and EG generated by the polycondensation reaction only needs to be removed from the system.

  As an optimum reactor for such operation, an apparatus as shown in FIG. 3 is desirable. In the figure, reference numeral 71 denotes a long cylindrical container body, the outer periphery of which is covered with a heat medium jacket 72, and a downcomer pipe 73 whose upper part is open in the longitudinal direction of the center of the main body 71 is attached. A plurality of heat transfer tubes 74 are attached to the lower portion of the main body 71 in parallel with the downcomer tube 73, and a plurality of spiral baffle plates 75 are attached to the outside of the downcomer tube 73 above the heat transfer tube 74. Each baffle plate 75 has a gap 83 for allowing volatiles to escape between the inner wall of the main body 71 and partitions the main body 71 in the vertical direction to form a plurality of retention chambers 84. A space 76 for separating the liquid to be processed and volatile substances is provided in the upper part of the main body 71, that is, at the upper ends of the downcomer 73 and the uppermost baffle plate 75C. In addition, a plurality of tapered liquid receivers 88 are attached to the inside of the down penetrating 73 inside the down pipe 73 for flowing the liquid to be processed into a thin film, and the liquid to be processed flowing down the down pipe 73 is supplied to each liquid. Since it can hold | maintain at the receptacle 88 and can be moved below sequentially, the short path | pass of a to-be-processed liquid can be decreased, and a reaction can be advanced by evaporating and separating volatiles efficiently.

In such an apparatus, the liquid to be treated continuously supplied from the inlet nozzle 77 first enters the heat transfer tube 74 and rises while being heated, and reaches the lowermost residence chamber 84A. The polycondensation reaction proceeds while the residence chamber 84A is gradually raised, and the generated volatile matter such as ethylene glycol moves upward from the gap 83 outside the baffle plate 75. On the other hand, the liquid to be treated rises while causing a swirling flow along the spiral portion of the baffle plate 75 and flows into the next staying chamber 84B. At this time, since it smoothly moves to the next staying chamber 84B while turning, there is little backflow, and the liquid to be treated sequentially rises in the staying portion, and the polycondensation reaction proceeds efficiently.

  In this way, the liquid to be processed that has reached the uppermost residence chamber 84C passes over the top portion 82 of the downcomer 73 and flows down inside the downcomer 73. The liquid to be treated flows down as a thin film inside the downcomer 73, and the volatiles generated by the reaction can be evaporated and separated to further proceed the polycondensation reaction. In this way, the volatiles are separated by evaporation, and the liquid to be treated which has undergone the reaction is discharged out of the system from the outlet nozzle 78. On the other hand, the generated volatile matter is separated from the splash of the liquid to be treated (polymerized product) in the upper space 6 in the main body, and discharged from the volatile matter outlet nozzle 79 to the outside of the system.

  At this time, a problem that the liquid to be treated (polymer) is accompanied by the volatile matter, that is, droplet entrainment is likely to occur, but in the present invention, the liquid to be treated and the volatile matter that bounce upward are directed in the circumferential direction by the spiral baffle plate 75 Can be suppressed. Volatile matter generated by such an apparatus, that is, EG, is vaporized in the gas phase portion 9 maintained in a reduced pressure atmosphere, condensed by a condenser provided on the upstream side thereof, and then discharged outside the system. As an advantage of the present invention, the number of condensers can be reduced to one by treating the initial polymerization process in a single reactor, reducing the number of pipes and valves as well as the number of condensers and the number of control devices. This greatly reduces the equipment cost. The processing liquid that has passed a predetermined reaction time in the initial polymerization tank (second reactor) 37 is supplied to the final polymerization machine (third reactor) 41 through the communication tube 40. In the final polymerization machine, a polymer having the desired degree of polymerization is produced by further proceeding with the polycondensation reaction while receiving a good surface renewal action by the stirring blade 42 having no stirring shaft at the center, thereby increasing the degree of polymerization.

As the optimum apparatus for the final polymerization machine (third reactor), the apparatus shown in FIGS. 4 and 15 has the most excellent surface renewal performance and power consumption characteristics. In addition, since the viscosity range of the treatment liquid is wide, it is possible to use a single apparatus to perform treatment by dividing into two tanks, and the apparatus cost is greatly reduced. The final polymerization machine will be described with reference to FIG. FIG. 4 is a front view showing a longitudinal section of the apparatus of the present invention. In the figure, 1 is a horizontally long cylindrical container body whose outer periphery is covered with a heat medium jacket (not shown), and rotation support shafts 3a and 3b are attached to both ends in the longitudinal direction. A stirring rotor 4 is attached between the rotation supporting shafts 3a and 3b, and one rotating shaft 3a is connected to a drive device (not shown). This stirring rotor 4 has 5a, 5b, 5c,
5d (in the present embodiment, four cases are shown, but the number to be used is determined depending on the size of the rotor) and the rotor support members 2a and 2b are connected. A stirring rotor 4 composed of a stirring block is formed. The support member 2a is a low viscosity side member, and 2b is a high viscosity side support member. The support member 2b is configured to be smaller than the outer diameter of the agitation rotor 4, and oyster members 13a and 13b are provided on the side surface of the main body of the support member, and the processing liquid on the side wall surface of the main body is pushed out to the outer peripheral portion by the rotation of the rotor. It is attached as follows. A detailed configuration is shown in FIG. 14, which is an EE cross section of FIG.

The agitation rotor 4 has a low-viscosity agitation block composed of a bucket part composed of oyster plates 6a and 6b and a thin disk 7a into which the processing liquid is poured from the bucket part and a hollow disk 8 in the low-viscosity area on the inlet nozzle 11 side. (The detailed structure will be described with reference to FIGS. 5, 9, and 10). Next, in the medium viscosity region, hollow disks 8 are arranged on both sides, a plurality of hollow thin plates 7b having the same outer diameter are installed therein, and a plurality of oyster plates 6c penetrating these members are radially provided on the outer periphery. A medium-viscosity agitation block (configured in detail with reference to FIGS. 3, 4, 8, and 9) is provided. Further, a plurality of wheel-shaped discs 9 are installed at appropriate intervals on the outlet side, and a oyster plate 10 is installed on the outer periphery of the wheel-shaped disc 9 to show a high viscosity stirring block (detailed structure is shown in FIG. This will be described with reference to FIG. Further, an outlet nozzle 11 for the liquid to be processed is attached to the lower portion of the other end of the main body 1. Further, an outlet nozzle 14 for volatile substances is provided in the upper part of the main body 1, and is connected to a condenser and a vacuuming device (not shown) by piping.

In such an apparatus, the low-viscosity liquid (prepolymer) having a low degree of polymerization supplied continuously from the inlet nozzle 11 is first stirred by the low-viscosity stirring block shown in FIG. The viscosity of the treatment liquid at this time is several Pas to several tens Pas. The low-viscosity stirring block forms buckets on the outer peripheral portion of the hollow disk 8 with oyster plates 6a and 6b. When rotated as shown in the figure, it operates to scoop up the processing liquid into the bucket. 9 and 10 schematically show the flow state of the treatment liquid at this time. A small gap δ is formed at the bottom of the bucket of the oyster board 6a, 6b. For this reason, the low-viscosity processing liquid 91 is scooped up in the bucket along with the rotation of the stirring rotor (100 in FIG. 9), and the processing liquid flows inward by the bucket rotating (101 in FIG. 9) and also outwards. It leaks little by little (102 in FIG. 9), and forms liquid films 101 and 102 on both the inside and outside of the bucket. Further, the processing liquid 101 that has flowed inward is poured into the thin plate disk 7a installed at the tip of the inner bucket (103 in FIG. 10), and the surface of the thin plate disk 7a and the thin plate disk 7a and the thin plate disk 7a. A thin liquid film is formed on both sides, and a wide evaporation surface area can be secured.

  These actions are repeated each time the bucket rotates, and a sufficient evaporation surface and a good surface renewal action can be obtained. At this time, a sufficiently good performance can be obtained even at a low speed (less than 10 rpm) of 0.5 to several rpm, and a great effect can be obtained in reducing the power consumed by stirring. Further, the by-product evaporated from the treatment liquid passes through the hollow portion 20a of the hollow disc 20a and the hollow portion 20a of the thin disc 7a and is discharged from the outlet nozzle 14 for volatile substances. The processing liquid that has passed a predetermined residence time in the low viscosity stirring block increases the viscosity to about several tens of Pas and reaches the next medium viscosity stirring block.

  The detailed structure of the medium viscosity stirring blade block is shown in FIGS. The medium-viscosity stirring blade block is composed of a hollow disk 8, a thin hollow disk 7b, and a oyster board 6c. The hole diameter D1 of the hollow disk and the hole diameter D3 of the thin disk 7b depend on the amount of reaction by-product gas in the processing liquid. Accordingly, it is determined so as to obtain an optimum diameter. The optimum diameter of the hole diameter D2 of the thin disk 7b is determined according to the viscosity of the processing liquid and the amount of reaction gas. As shown in FIGS. 11 and 12, the processing liquid 92 having reached several tens of Pas is lifted by the oyster plate 6 c by rotation, and further, the liquid drips and forms a liquid film 104 because the oyster plate is inclined by rotation. The liquid film 104 hangs on the connecting strength member 5a of the stirring rotor with rotation, and the liquid film is held for a long time. In addition, the processing liquid drawn up by the rotation drips down inside the hollow portion 20 a of the hollow disk 8 to form a liquid film 105. In addition, the liquid film 107 is similarly formed on the thin plate disk 7b. However, the processing liquid drips also on the small holes 20b provided in the thin plate disk 7b to form the liquid film 106. The treatment liquid further increases the degree of polymerization and increases the viscosity of the treatment liquid due to the large evaporation surface area and good surface renewal action while forming such a liquid film. When the treatment liquid viscosity reaches several hundred Pas, it is treated in the next high viscosity stirring block.

In the stirring block for high viscosity, a oyster plate 10a is attached to the outer periphery of a wheel-type disc 9 as shown in FIG. Such a wheel-type disk 9 is connected at a predetermined interval by stirring strength members 5a, 5b, 5c, and 5d in the horizontal direction. At this time, the oyster plates before and after the wheel-type disc 9 are alternately installed as 10a and 10b, and the horizontal length of the oyster plate is such that the trajectories of the tip portions overlap each other when the disc rotates. The entire inner wall is scraped off. As shown in FIG. 13, the processing liquid 93 that reaches several hundred Pas is lifted by the oyster plate 10a by the rotation of the stirring blade. The lifted processing liquid drips by rotation to form a liquid film 108. At this time, a liquid film 109 is also formed in the hollow portion of the wheel-type disk 9 to create a complicated liquid surface shape. When the viscosity of the treatment liquid further increases and reaches several thousand Pas, the amount of liquid that is lifted increases. If the rotational speed is increased in such a state, a circulating phenomenon occurs in which the liquid is again picked up before the processing liquid drips down. Therefore, it is necessary to operate at a rotational speed of 10 rpm or less. The optimum operating range needs to be lowered as the viscosity of the treatment liquid is higher. In this experiment, the range of 0.5 to 6 rpm was optimum. As described above, the polycondensation reaction is promoted by repeating the stirring and the surface renewal action. The volatile matter generated by the reaction sequentially moves in the longitudinal direction in the main body 1 through the hollow portion of the hollow disc, and is discharged out of the system from the volatile nozzle 14. The liquid to be treated having a high degree of polymerization and a high viscosity in this manner is discharged out of the system from the outlet nozzle 12.

  At this time, the treatment liquid having a high viscosity accumulates in the upper portion of the outlet nozzle 12, but does not adhere to the support member 2 b because the outer diameter of the support member 2 b of the stirring rotor is smaller than the outer diameter of the stirring rotor 4. Further, oyster members 13a and 13b are attached to the side surface of the main body 1 of the support member 2b, and the processing liquid is pressed against the outer peripheral portion of the main body, so that the main body side wall surface is always self-cleaned to prevent adhesion and retention.

  When polymerizing polyethylene terephthalate with such an apparatus, the intermediate polymer of the liquid to be treated is continuously supplied from the inlet nozzle 11, stirred by the stirring rotor 4, and the surface is renewed to volatilize ethylene glycol or the like generated by the polymerization reaction. The product is removed by evaporation, and the polycondensation reaction proceeds to give a highly viscous polymer. Volatile substances such as ethylene glycol separated during this time are discharged from the outlet nozzle 14. The operating conditions at this time are, for example, a liquid temperature of 260 to 300 ° C., a pressure of 0.01 to 10 kPa, and a rotation speed of 1 to 10 rpm. Then, the polymer is discharged out of the system from the outlet nozzle 12. At this time, the polymer is stirred in the main body 1 in an almost complete self-cleaning state and is subjected to good surface renewal, so that a high-quality product polymer can be efficiently obtained without deterioration due to retention. Similarly, this apparatus can be applied to continuous bulk polymerization of polycondensation resins such as polyethylene naphthalate, polyamide, and polycarbonate. The final polymerization machine in FIG. 15 has the same basic configuration as the apparatus shown in FIG. 4, but shows an embodiment of the apparatus in which the low-viscosity blade portion is omitted when the treatment liquid viscosity at the inlet is relatively high. It is a thing. The stirring block for high viscosity has a plurality of wheel-shaped discs 9 installed at appropriate intervals, and a oyster plate 200 is connected to the outer periphery of the wheel-shaped disc 9 to form a next wheel-shaped disc. The oyster plate 200 between the plates 9 is formed by shifting the mounting position to form a high viscosity stirring block.

  When polyethylene terephthalate is produced in the above apparatus configuration, the number of reactors is reduced as compared with the conventional apparatus configuration, so that the cost of the apparatus can be saved and the distillation column attached to the apparatus as the number of apparatuses decreases. This reduces the number of condensers and condensers, greatly reduces the piping, instrumentation parts, and valves that connect them, and significantly reduces utility costs such as vacuum sources and heat transfer devices, thereby lowering running costs.

  It can be applied to continuous production of polyester polymers such as polyethylene terephthalate and polybutylene terephthalate.

It is a block diagram which shows one Example of the continuous manufacturing process of the polyethylene terephthalate by this invention. 1 is a convenient cross-sectional view showing an embodiment of an evaporator according to the present invention. It is a longitudinal cross-sectional front view which shows one Example of this invention. It is a longitudinal cross-sectional front view which shows one Example of this invention. It is the sectional view on the AA line of FIG. It is the BB sectional view taken on the line of FIG. It is CC sectional view taken on the line of FIG. It is the DD sectional view taken on the line of FIG. It is a schematic diagram of the flow of the process liquid of the bucket part of a low-viscosity stirring block. It is a schematic diagram of the flow of the processing liquid near the thin disk disk of a low-viscosity stirring block. It is a schematic diagram of the flow of the process liquid near the hollow disc of a medium viscosity stirring block. It is a schematic diagram of the flow of the thin disk-shaped process liquid of a medium viscosity stirring block. It is a schematic diagram of the flow of the process liquid of a high-viscosity stirring block. It is the EE sectional view taken on the line of FIG. It is a longitudinal cross-sectional front view which shows one Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Container main body, 3a, 3b ... Shaft for rotation support, 4 ... Stirring rotor, 5a, 5b, 5c,
5d: Strength member for constituting the stirring rotor, 2a, 2b ... Rotor support member, 6a, 6b, 6c, 10, 10a, 10b, 200 ... Kakitori plate, 7a, 7b ... Thin plate disk, 8 ... Hollow disc, 9 DESCRIPTION OF SYMBOLS Wheel shape disk, 11 ... Inlet nozzle, 12 ... Outlet nozzle, 13a, 13b ... A oyster member, 14 ... Outlet nozzle of volatile matter, 20a, 20b, 20c ... Hollow part, 31 ... Raw material adjustment tank, 32 ... Raw material supply 33, esterification reaction tank, 34, 38 ... heat exchanger, 35, 39 ... gas phase section, 36, 40 ... communication pipe, 37 ... initial polymerization tank, 41 ... final polymerization machine, 42 ... stirring blade, 43 ... Polymer, 44 ... Stirring power source, 51 ... Evaporator, 52 ... Liquid to be treated, 54 ... Multi-tube heat exchanger, 56 ... Run-up space, 62 ... Conical member, 71 ... Container body, 72 ... Heat medium jacket 73 ... Downcomer pipes, 74 ... Heat transfer tubes, 75 ... Baffles spiral, 76 ... volatiles separation space, 77 ... inlet nozzle of the liquid to be treated, 78 ... outlet nozzle of the liquid to be treated, 79 ... volatiles outlet nozzle, 91 and 92,
93... Treatment liquid level, 100, 101, 102, 103, 104, 105, 106, 107, 109, 110.

Claims (2)

A substantially horizontal cylindrical container main body has an inlet nozzle and an outlet nozzle for the liquid to be processed at the lower end and the lower end of the other end, respectively, and a volatiles outlet nozzle at the upper portion of the main body. In the continuous polycondensation apparatus provided with a stirring rotor that rotates close to the inside of the main body,
The stirring rotor has a rotor support member connected to a plurality of strength members without having a rotating shaft at the center of the stirring rotor at both ends, and has a low viscosity corresponding to the viscosity of the treatment liquid formed between the support members. A bucket portion comprising a plurality of oyster plates, each of which is provided in a low viscosity region on the inlet nozzle side of the liquid to be treated. And a low-viscosity stirring block consisting of a thin disk and a hollow disk into which the processing liquid is poured from the bucket part,
Provided in the medium viscosity range, with hollow discs on both sides, multiple hollow thin plates with the same outer diameter installed in it, and multiple oyster plates that penetrate these members on the outer periphery. Medium viscosity stirring block configured
A high viscosity region is provided in the high viscosity region on the outlet nozzle side of the liquid to be treated, and a plurality of discs having a hollow portion in the wheel mold are installed at appropriate intervals, and oyster plates are alternately arranged on the outer periphery of the disc. It consists of a viscosity stirring block,
A continuous polycondensation apparatus, comprising: a oyster member that pushes the processing liquid on the side wall surface of the main body toward the outer peripheral portion by rotation of the stirring rotor on the side surface of the main body of the rotor support member on the volatile matter outlet nozzle side. A substantially horizontal cylindrical container main body has an inlet nozzle and an outlet nozzle for the liquid to be processed at the lower end and the lower end of the other end, respectively, and a volatiles outlet nozzle at the upper portion of the main body. A stirring rotor that rotates close to the inside of the main body,
The stirring rotor has a rotor support member connected to a plurality of strength members without having a rotating shaft at the center of the stirring rotor at both ends, and has a low viscosity corresponding to the viscosity of the treatment liquid formed between the support members. A bucket portion comprising a plurality of oyster plates, each of which is provided in a low viscosity region on the inlet nozzle side of the liquid to be treated. And a low-viscosity stirring block consisting of a thin disk and a hollow disk into which the processing liquid is poured from the bucket part,
Provided in the medium viscosity range, with hollow discs on both sides, multiple hollow thin plates with the same outer diameter installed in it, and multiple oyster plates that penetrate these members on the outer periphery. Medium viscosity stirring block configured
A high viscosity region is provided in the high viscosity region on the outlet nozzle side of the liquid to be treated, and a plurality of discs having a hollow portion in the wheel mold are installed at appropriate intervals, and oyster plates are alternately arranged on the outer periphery of the disc. It consists of a viscosity stirring block,
A continuous polycondensation apparatus having a oyster member that pushes the processing liquid on the side wall surface of the main body to the outer peripheral portion by rotation of the stirring rotor on the main body side surface of the rotor support member on the outlet nozzle side of the volatile matter,
Using the continuous polycondensation apparatus, a prepolymer having a low degree of polymerization is continuously supplied from the inlet nozzle of the liquid to be processed, and the processing liquid is stirred by rotating the stirring rotor while forming a liquid film by each stirring block. The polycondensation of the polyester polymer is performed by renewing the surface of the treatment liquid to evaporate volatiles and moving it toward the outlet nozzle of the liquid to be treated to increase the degree of polymerization. .

Images