JP2004002901A - Method and apparatus for producing polyester - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a continuous production method for polyethylene terephthalate wherein the number of reactors necessary for reaction is made minimal and the power consumption for agitation necessary for reaction are minimized by providing a production method and apparatus whereby a high-quality polyester is efficiently produced by using three reactors. <P>SOLUTION: The polyester production apparatus has three reactors: an esterification reactor, an initial polymerization reactor, and a final polymerization reactor. Both the esterification reactor and the initial polymerization reactor are not equipped with an external power source for agitation. The final polymerization reactor is of a horizontal single-shaft low-speed-rotating type. Such a necessary and minimum reactor constitution enables a high-quality polyester to be efficiently produced at a minimum energy cost. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a method and an apparatus for continuously producing polyester-based 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, two to three stirring tanks with stirring blades are arranged in series, and water produced as a by-product is separated by a distillation column. Next, a plurality of vertical stirring tanks and horizontal stirring tanks are installed as a pre-polymerization step, and a horizontal stirring tank is installed as a final polymerization step. A condenser is installed in the tank for these polymerization steps to remove ethylene glycol as a by-product, and the vessel is operated in a reduced pressure atmosphere. In the conventional polyester production 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 column and condenser for separating and removing by-products are installed. ing. Further, 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 equipment costs.

JP-A-7-20709

The problem of the present invention is an improvement over known processes for the production of high molecular weight polyesters, which increases the efficiency of the whole apparatus and operates more economically by saving energy of factory equipment.

An object of the present invention is to provide a continuous polycondensation apparatus and a continuous polycondensation method that improve the above-mentioned conventional technology and efficiently react a high-quality polymer with minimum energy by using a minimum necessary reactor configuration. is there.

(4) The above object can be achieved by making the esterification step, the pre-polymerization step, and the final polymerization step one tank each, and using only the final polymerization step as a tank requiring stirring power.

ADVANTAGE OF THE INVENTION According to this invention, the efficiency of the whole apparatus is improved by making the continuous production equipment of polyester into three reactors of an esterification process, a pre-polymerization process, and a final polymerization process, and it is economical by the energy saving of a factory equipment. To operate.

With the aim of reacting high quality polymer efficiently with minimum energy by the minimum necessary reactor configuration, the continuous production equipment for polyester was converted into three reactors of esterification process, prepolymerization 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 the industrial polyester production method, the direct esterification method is very economically advantageous, and thus the direct esterification method has recently been widely used. In the figure, reference numeral 31 denotes a raw material adjusting tank for mixing and stirring TPA (terephthalic acid) and EG (ethylene glycol) as raw materials of polyethylene terephthalate at a predetermined ratio. During 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 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 catalysts used, but also the hue and thermal stability of the produced polyester. It is well known that they are different. Furthermore, these reactions are carried out at a high temperature for a long time in the presence of a catalyst, and are accompanied by various side reactions, and the polymer is colored yellow, and the content of diethylene glycol (DEG) and the terminal carboxyl group concentration are more than appropriate values. And physical properties such as a decrease in the melting point and strength of the polyester are reduced. Attempts have been made to develop new catalysts in order to improve such problems, but antimony compounds, which are most industrially used at present, particularly antimony triacid, are excellent in price and performance. However, even if this catalyst is used, coloring of the produced polyester polymer cannot be avoided. For this reason, the use of a phosphorus-based stabilizer (eg, trimethyl phosphate, triphenyl phosphate) as a stabilizer has been improved. Further, in another manufacturing process, the quality is stabilized by devising a position where a polymerization catalyst and a stabilizer are charged. In a normal process, it is preferable to use 200 to 400 ppm of the catalyst and 50 to 200 ppm of the stabilizer.

The raw material adjusted as described above goes through a supply line 32 that supplies 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) for keeping the processing liquid at the reaction temperature. An exchanger 34 is provided to heat the processing liquid by an external heat source, and to proceed the reaction while circulating the internal liquid by natural circulation. Here, the most desirable type of reactor is a calandria type in which the processing solution in the reactor is naturally circulated by utilizing the evaporating action of a by-product produced by the esterification reaction by its own reaction. Since this type of reactor does not require an external stirring power source, there is an advantage that the apparatus configuration is simple, 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 the present apparatus. The liquid to be treated 52 flows through an inlet 53 provided at a lower portion in the vertical evaporator 1, flows through a plurality of heat transfer tubes (not shown) of the multi-tube heat exchanger 4, is heated, and is subjected to natural convection. To rise. Here, a part of the low boiling point component of the liquid to be treated 52 evaporates and is 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 the cylindrical liquid provided at the lower part of the shell of the multitubular heat exchanger 4. Flows into the approach space 56. Here, the flow of the processing liquid is rectified with less turbulence, and the average flow velocity in the tubes of the multi-tube heat exchanger 54 is increased more than the average flow velocity flowing down by natural convection, so that a more uniform velocity is obtained. The liquid 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 components evaporate gradually, and after a suitable convection time, the liquid to be treated 59 concentrated 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 approach space is designed to be larger than the total flow passage area of the heat transfer tubes, and further, the multi-tube heat exchange with the inner wall of the evaporator 51 is performed. This is achieved by making the flow area of the double pipe section formed between the outer wall of the shell of the vessel 54 and the flow path area of the entrance space larger. Reference numeral 57 denotes an inlet for the heat medium, and 58 denotes an outlet for the heat medium. The evaporator 51 is surrounded by a heat insulating material or a jacket (not shown).

Therefore, in the evaporator of this embodiment, the velocity distribution is uniform along the axial direction of the heat exchanger, so that the liquid to be treated can more uniformly evaporate or react, and a better product quality can be obtained with a short residence time. There is an effect that can be obtained. Even when the liquid to be treated 52 is a mixture of solid particles and a liquid (hereinafter referred to as slurry), the liquid to be treated 52 that naturally circulates is formed into a cylindrical entrance space 56 provided below the shell of the multi-tube heat exchanger 54. , But rises more smoothly along the conical member 62 so that solid particles do not settle to the bottom. When the liquid to be treated is a slurry, a conical member for raising the liquid to be treated internally circulating is provided at the bottom of the evaporator, so that precipitation of solid particles contained in the slurry can be prevented. Here, the conical member may have a certain curvature. Therefore, the evaporator of the present embodiment has an effect of providing a suitable evaporator by natural circulation of the slurry, and a reliable and good quality product can be obtained. However, the present invention is not limited to this apparatus, and a reactor having a stirring blade may be used for process reasons.

水 In the first reactor, the water generated by the reaction becomes steam, and forms the vapor phase portion 5 with the vaporized EG vapor. At this time, as the recommended reaction conditions, the temperature is preferably 240 to 280 degrees, and the pressurization condition is desirable. The gas in the gas phase 5 is separated into water and EG by a rectification tower (not shown) provided on the upstream side, the water is removed outside 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 for controlling the number of pipes and valves can be reduced. The number and the like can be reduced, resulting in a significant reduction in equipment cost. The processing solution having passed a predetermined reaction time in the esterification reaction tank 33 reaches a predetermined esterification rate, and is supplied to the initial polymerization tank (second reactor) 37 through the communication pipe 36. At this time, the treatment liquid is heated to a predetermined reaction temperature by the heat exchanger 38 to perform a polycondensation reaction to increase the degree of polymerization. At this time, the reaction conditions are from 270 to 290 degrees, the pressure is from 266 to 133 Pa, and the degree of polymerization is from about 20 to 40.

初期 Although the initial polymerization tank described in this example is described using a reactor having no stirring blade, the reactor is not limited to this. However, in the initial polymerization stage, the reaction is a stage in which the polymerization reaction rate is governed by the rate of the reaction, 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 only EG generated by the polycondensation reaction needs to be separated out of the system.

装置 As a reactor most suitable for such an operation, an apparatus as shown in FIG. 3 is desirable. In the figure, reference numeral 71 denotes a vertically cylindrical container main body, the outer periphery of which is covered with a heat medium jacket 72, and a downcomer 73 whose upper part is opened in the central longitudinal direction of the main body 71 is attached. A plurality of heat transfer tubes 74 are attached to the lower portion inside the main body 71 in parallel with the downcomer tube 73, and a plurality of spiral baffle plates 75 are attached to the outer side of the downcomer tube 73 above the heat transfer tube 74. Each of the baffles 75 has a gap 83 for allowing volatiles to escape from the inner wall of the main body 71 and vertically partitions the inside of the main body 71 to form a plurality of retention chambers 84. A space 76 for separating the liquid to be treated and the volatiles is provided at the upper part in the main body 71, that is, at the upper end of the downcomer 73 and the uppermost baffle 75C. Further, a plurality of tapered liquid receivers 88 are attached inside the descending pipe 73 for allowing the liquid to be treated to flow down the thin film inside the descending penetrator 73, and the liquid to be treated flowing down the descending pipe 73 is supplied to each liquid. Since the liquid can be sequentially moved downward while being held in the receiver 88, the short path of the liquid to be treated can be reduced, and the reaction can be efficiently performed by evaporating and separating volatiles.

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 retention chamber 84A. The polycondensation reaction proceeds while gradually ascending the retention chamber 84A, 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 processed rises while causing a swirling flow along the spiral portion of the baffle plate 75, and flows into the next retaining chamber 84B. At this time, since the liquid moves smoothly to the next retaining chamber 84B while turning, the liquid to be treated gradually rises in the retaining portion, and the polycondensation reaction proceeds efficiently with little backflow.

(5) The liquid to be processed that has reached the uppermost retaining chamber 84C in this way passes over the top 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 volatiles generated by the reaction are evaporated and separated, so that the polycondensation reaction can be further advanced. In this way, the volatile substances are evaporated and separated, and the liquid to be treated after the reaction is discharged out of the system from the outlet nozzle 78. On the other hand, the generated volatiles are separated from droplets of the liquid to be treated (polymer) in the upper space 6 in the main body, and are discharged out of the system from the outlet nozzle 79 for the volatiles.

At this time, the problem that the liquid to be treated (polymer) accompanies the volatile substance, that is, the entrainment is apt to occur, but in the present invention, the liquid to be treated and the volatile substance bumping upward by the spiral baffle plate 75 are directed in the circumferential direction. Can be suppressed, and the droplets can be suppressed. Volatile matter, EG, generated by such a device is vaporized in the gas phase section 9 kept in a reduced pressure atmosphere, condensed by a condenser provided on the upstream side thereof, and then discharged out of the system. As an advantage of the present invention, it is possible to reduce the number of condensers by processing the initial polymerization step in one reactor, thereby reducing not only the production cost of the condenser but also the number of piping and valves and the number of control devices. As a result, the cost of the apparatus is greatly reduced. The treatment liquid having 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 pipe 40. In the final polymerization machine, a polycondensation reaction is further promoted while undergoing a good surface renewing action by a stirring blade 42 having no stirring shaft at the center to increase the degree of polymerization to produce a polymer having a desired degree of polymerization.

As the most suitable device as the final polymerization machine (third reactor), the devices shown in FIGS. 4 and 15 have the best surface renewal performance and power consumption characteristics. Further, since the viscosity range of the processing liquid is wide, the processing which has been conventionally performed by dividing the processing liquid into two tanks can be performed by one apparatus, and the cost of the apparatus can be 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 device of the present invention. In the drawing, reference numeral 1 denotes a horizontally long cylindrical container body whose outer periphery is covered with a heat medium jacket (not shown), and shafts 3a and 3b for rotation support are attached to both ends in the longitudinal direction. A stirring rotor 4 is mounted between the rotation supporting shafts 3a and 3b, and one of the rotation shafts 3a is connected to a driving device (not shown). This stirring rotor 4 has 5a, 5b, 5c,
5d (in this embodiment, four rotors are shown, but the number of rotors used is determined by the size of the rotor), and a plurality of rotor support members 2a and 2b are connected. The 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 supporting member 2b is configured to be smaller than the outer diameter of the stirring rotor 4, and oyster members 13a and 13b are provided on the side of the main body of the supporting member, and the processing liquid on the side wall of the main body is pushed to the outer peripheral portion by the rotation of the rotor. So that it is attached. The detailed configuration is shown in FIG. 14, which is an EE section in FIG.

The stirring rotor 4 has a low-viscosity block on the side of the inlet nozzle 11 in which a low-viscosity stirring block is constituted by a bucket portion composed of oyster plates 6a and 6b, a thin disk 7a into which the processing liquid is poured from the bucket portion, and a hollow disk 8. (The detailed structure will be described with reference to FIGS. 5, 9, and 10). Next, a hollow disk 8 is disposed on both sides of the medium viscosity region, 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 further radially provided on the outer peripheral portion. A medium-viscosity stirrer block (detailed structure will be described with reference to FIGS. 3, 4, 8, and 9) is provided. Further, on the outlet side, a plurality of wheel-shaped disks 9 are installed at appropriate intervals, and an oyster plate 10 is installed on the outer periphery of the wheel-shaped disks 9 to provide a high-viscosity stirring block (see FIG. FIG. 13) is provided. At the lower end of the other end of the main body 1, an outlet nozzle 11 for the liquid to be treated is attached. Further, a volatile matter outlet nozzle 14 is provided at an upper portion of the main body 1 and connected to a condenser and a vacuuming device (not shown) by piping.

In such an apparatus, a low-viscosity liquid to be treated (prepolymer) having a low degree of polymerization and continuously supplied from the inlet nozzle 11 is first stirred in a low-viscosity stirring block shown in FIG. The viscosity of the processing liquid at this time is several Pas to several tens Pas. The low-viscosity stirring block forms a bucket on the outer periphery of the hollow disk 8 with the oyster plates 6a and 6b. When it rotates as shown in the figure, it operates to scoop up the processing liquid in the bucket. FIGS. 9 and 10 schematically show the flow state of the processing liquid at this time. A small gap δ is formed at the bottom of the bucket of the oyster plates 6a and 6b. Therefore, the low-viscosity processing liquid 91 is picked up by the bucket with the rotation of the stirring rotor (100 in FIG. 9), and the bucket tilts inward due to the rotation, and the processing liquid flows out to the inside (101 in FIG. 9) and also to the outside. The liquid films 101 and 102 are formed on both the inside and outside of the bucket by leaking little by little (102 in FIG. 9). Further, the processing liquid 101 which has flowed inward is poured into the thin disk 7a installed at the tip of the inner bucket (103 in FIG. 10), and the surface of the thin disk 7a and the thin disk 7a and the thin disk 7a A thin liquid film is formed on both sides, and a wide evaporation surface area can be secured.

These actions are repeated every time the bucket rotates, and a sufficient evaporation surface and good surface renewal action can be obtained. At this time, sufficiently good performance can be obtained even at a low speed of 0.5 to several rpm (10 rpm or less), and a great effect can be obtained in reducing the power consumed by stirring. The by-product evaporated from the processing liquid passes through the hollow portion 20a of the hollow disk 8 and the hollow portion 20a of the thin disk 7a and is discharged from the volatile matter outlet nozzle 14. The treatment liquid having passed a predetermined residence time in the low-viscosity stirring block raises the viscosity to about several tens Pas and reaches the next medium-viscosity stirring block.

(6) The detailed structure of the medium viscosity stirring blade block is shown in FIGS. The medium-viscosity stirrer block is composed of a hollow disk 8, a thin hollow disk 7b and an oyster plate 6c. The hole diameter D1 of the hollow disk and the hole diameter D3 of the thin disk 7b are determined by the amount of reaction by-product gas in the processing liquid. The diameter is determined so as to be the optimum diameter. The optimum diameter of the hole diameter D2 of the thin disk 7b is also determined according to the viscosity of the processing liquid and the amount of the reaction gas. The processing liquid 92 having several tens Pas is lifted up by the oscillating plate 6c by rotation as shown in FIGS. 11 and 12, and furthermore, the oscillating plate is inclined by the rotation, so that the liquid hangs down to form a liquid film 104. The liquid film 104 hangs on the connection strength member 5a of the stirring rotor with rotation, and the liquid film is held for a long time. In addition, the processing liquid dragged by the rotation is dripped in the hollow portion 20 a of the hollow disk 8 to form a liquid film 105. The liquid film 107 is also formed on the thin disk 7b, but the processing liquid also drips down into the small holes 20b provided on the thin disk 7b to form the liquid film 106. While forming such a liquid film, the treatment liquid further increases the degree of polymerization due to a large evaporation surface area and a good surface renewal action, and the viscosity of the treatment liquid increases. When the viscosity of the treatment liquid reaches several hundred Pas, it is treated by the next high viscosity stirring block.

In the stirring block for high viscosity, an oyster plate 10a is attached to an outer peripheral portion of a wheel-shaped disk 9 as shown in FIG. Such wheel-shaped discs 9 are horizontally connected at predetermined intervals by stirring strength members 5a, 5b, 5c, 5d. At this time, the oyster plates before and after the wheel-shaped disk 9 are alternately set as 10a and 10b, and the horizontal length of the oyster plate is such that the trajectories of the tips overlap each other when the disk rotates, and The entire inner wall is scraped. As shown in FIG. 13, the treatment liquid 93 which has reached several hundred Pas is lifted by the oyster plate 10a by the rotation of the stirring blade. The lifted processing liquid is dripped 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-shaped disc 9 to create a complicated liquid surface shape. When the viscosity of the processing liquid further increases and reaches several thousand Pas, the amount of the liquid lifted also increases. If the number of revolutions is increased in such a state, a rotating phenomenon occurs in which the processing liquid is stirred up again before the treatment liquid drips. Therefore, it is necessary to operate at a number of revolutions of 10 rpm or less. The optimum operating range needs to be lowered as the viscosity of the processing liquid increases, and in our experiments, the optimum range was 0.5 to 6 rpm. As described above, the agitation and the surface renewal action are repeated to promote the polycondensation reaction. The volatiles generated by the reaction move sequentially in the longitudinal direction in the main body 1 through the hollow portion of the hollow disk, and are discharged from the volatile nozzle 14 to the outside of the system. The liquid to be treated having a high degree of polymerization and a high viscosity is discharged from the outlet nozzle 12 to the outside of the system.

{Circle around (4)} At this time, the processing liquid having a high viscosity accumulates above the outlet nozzle 12, but does not adhere to the support member 2b because the outer diameter of the support member 2b of the stirring rotor is smaller than the outer diameter of the stirring rotor 4. Further, the 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 side wall surface of the main body is always self-cleaned to prevent adhesion and stagnation.

When polyethylene terephthalate is polymerized by such an apparatus, the intermediate polymer of the liquid to be treated is continuously supplied from the inlet nozzle 11 and the surface is renewed by stirring with the stirring rotor 4 to volatilize ethylene glycol and the like generated by the polymerization reaction. The product is removed by evaporation, and the polycondensation reaction proceeds to form a high-viscosity 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 from the outlet nozzle 12 to the outside of the system. At this time, the polymer is stirred in the body 1 in a substantially completely self-cleaning state and undergoes good surface renewal, so that a high quality product polymer can be efficiently obtained without deterioration due to stagnation. Similarly, the present apparatus can be applied to continuous bulk polymerization of polycondensation resins such as polyethylene naphthalate, polyamide, and polycarbonate. Although the final polymerization machine in FIG. 15 has the same basic configuration as the apparatus shown in FIG. 4, when the viscosity of the processing liquid at the inlet is relatively high, the embodiment of the apparatus in which the low viscosity blade portion is omitted is shown. It is a thing. In addition, a stirring block for high viscosity is provided with a plurality of wheel-shaped disks 9 at appropriate intervals, and an oyster plate 200 is connected to the outer periphery of the wheel-shaped disks 9 to form the next wheel-shaped disk. The oscillating plate 200 between the plates 9 is such that a mounting position is shifted to form a high-viscosity stirring block.

When polyethylene terephthalate is manufactured in the above-described apparatus configuration, the number of reactors is reduced as compared with the conventional apparatus configuration, so that the cost of the apparatus can be reduced. In addition, there is an advantage that the number of pipes, instrumentation parts and valves connecting them can be greatly reduced, and the running costs can be reduced because utility-related costs such as a vacuum source and a heating medium device are greatly reduced.

で き る Applicable to continuous production of polyester polymers such as polyethylene terephthalate and polybutylene terephthalate.

FIG. 1 is a configuration diagram showing one embodiment of a continuous production process of polyethylene terephthalate according to the present invention. FIG. 2 is a cross-sectional view for convenience showing an embodiment of the evaporator according to the present invention. It is a longitudinal section front view showing one example of the present invention. It is a longitudinal section front view showing one example of the present invention. FIG. 5 is a sectional view taken along line AA of FIG. 4. FIG. 2 is a sectional view taken along line BB of FIG. 1. FIG. 5 is a sectional view taken along line CC of FIG. 4. FIG. 5 is a sectional view taken along line DD of FIG. 4. It is a schematic diagram of the flow of the processing 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 of the low viscosity stirring block. It is a schematic diagram of the flow of the processing liquid near the hollow disk of the medium viscosity stirring block. It is a schematic diagram of the flow of the processing liquid of a thin disk shape of a medium viscosity stirring block. It is a schematic diagram of the flow of the processing liquid of a high viscosity stirring block. FIG. 5 is a sectional view taken along line EE of FIG. 4. It is a longitudinal section front view showing one example of the present invention.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 ... Container main body, 3a, 3b ... Shaft for rotation support, 4 ... Stirring rotor, 5a, 5b, 5c,
5d: strength member for agitating rotor configuration, 2a, 2b: rotor support member, 6a, 6b, 6c, 10, 10a, 10b, 200: oyster plate, 7a, 7b: thin disk, 8: hollow disk, 9 ... wheel-shaped disc, 11 ... inlet nozzle, 12 ... outlet nozzle, 13a, 13b ... oyster member, 14 ... volatile matter outlet nozzle, 20a, 20b, 20c ... hollow part, 31 ... raw material adjusting tank, 32 ... raw material supply Line, 33: Esterification reaction tank, 34, 38: Heat exchanger, 35, 39: Gas phase, 36, 40: Connecting tube, 37: Initial polymerization tank, 41: Final polymerization machine, 42: Stirring blade, 43 ... Polymer, 44 ... Agitation power source, 51 ... Evaporator, 52 ... Liquid to be treated, 54 ... Multitubular heat exchanger, 56 ... Running space, 62 ... Conical member, 71 ... Container body, 72 ... Heat medium jacket , 73 ... downcomer, 74 ... heat transfer tube, 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: Processing liquid level, 100, 101, 102, 103, 104, 105, 106, 107, 109, 110: Liquid film.

Claims (18)

A first reactor in which an aromatic dicarboxylic acid or a derivative thereof is reacted with a glycol to produce an oligoester or polyester having an average degree of polymerization of 3 to 7 or less; Polyester is produced by using a second reactor for producing a low-polymerized product of No. 40 and a third reactor for polycondensing the low-polymerized product further and polycondensing from an average degree of polymerization of 90 to 180 to produce a high-molecular-weight polyester. Wherein the at least one reactor of the first reactor and the second reactor is a reactor having no stirring function by an external power source. A first reactor in which an aromatic dicarboxylic acid or a derivative thereof is reacted with a glycol to produce an oligoester or polyester having an average degree of polymerization of 3 to 7 or less; Polyester is produced by using a second reactor for producing a low-polymerized product of No. 40 and a third reactor for polycondensing the low-polymerized product further and polycondensing from an average degree of polymerization of 90 to 180 to produce a high-molecular-weight polyester. In the method, the third reactor has an inlet and an outlet for the liquid to be treated at one lower end and the lower end at the other end in the longitudinal direction of the horizontal cylindrical container main body, has a volatile substance outlet at the upper part of the main body, A stirring rotor that rotates close to the inside of the main body in the longitudinal direction of the main body, and the stirring rotor inside the main body is composed of a plurality of stirring blade blocks according to the viscosity of the processing liquid, Continuous process for producing a polyester which is a reactor having a 撹袢 blade having no rotating shaft in the center of the over data. The method for continuously producing a polyester according to claim 1 or 2, wherein the molar ratio of the aromatic dicarboxylic acid or a derivative thereof as a raw material to the glycol is in the range of 1: 1.05 to 1: 2.0, The temperature of one reactor is 240 to 285 degrees, the pressure is 3 × 10 ⁵ Pa from atmospheric pressure, the temperature of the second reactor is 250 to 290 degrees, the pressure is 133 Pa from atmospheric pressure, and the temperature of the third reactor is A continuous method for producing polyester, wherein the method is operated at a temperature of 270 to 290 degrees and a pressure of 200 to 13.3 Pa. The continuous production method of polyester according to claim 3, wherein the rotation speed of the stirring blade of the third reactor is from 0.5 rpm to 10 rpm. 3. The continuous production method of a polyester according to claim 1, wherein the total reaction time of the first reactor, the second reactor and the third reactor is operated between 4 and 8 hours. Method. A first reactor for producing an oligoester or polyester having an average degree of polymerization of 3 to 7 or less by reacting an aromatic dicarboxylic acid or a derivative thereof with glycols; And a third reactor for producing a high-molecular-weight polyester by polycondensing the low-polymer and further polycondensing the low-polymer to an average degree of polymerization of 90 to 180. At least one reactor of the first reactor and the second reactor is a reactor having no stirring function by an external power source, and is a continuous production apparatus for polyester. A first reactor for producing an oligoester or polyester having an average degree of polymerization of 3 to 7 or less by reacting an aromatic dicarboxylic acid or a derivative thereof with glycols; And a third reactor for producing a high-molecular-weight polyester by polycondensing the low-polymer and further polycondensing the low-polymer to an average degree of polymerization of 90 to 180. The third reactor has an inlet and an outlet for the liquid to be treated at one lower end and the lower end at the other end in the longitudinal direction of the horizontal cylindrical container main body, has an outlet for volatiles at the upper part of the main body, and has a longitudinal direction inside the main body. A device provided with a stirring rotor that rotates close to the inside of the main body. The stirring rotor inside the main body is composed of a plurality of stirring blade blocks according to the viscosity of the processing liquid. Continuous production apparatus of a polyester which is a reactor having a 撹袢 wing with no. A mixture in which the molar ratio of the aromatic dicarboxylic acid or its derivative as a raw material to the glycols is in the range of 1: 1.05 to 1: 2.0 is supplied, the temperature is 240 to 285 degrees, and the pressure is 3 × from atmospheric pressure. A first reactor in which a reaction is performed under a condition of 10 ⁵ Pa, and a reactant from the first reactor are supplied. The reaction is performed at a temperature of 250 ° C. to 290 ° C. and a pressure of atmospheric pressure to 133 Pa. It comprises a second reactor to be carried out and three reactors to which the reactants are supplied and the reaction is carried out at a temperature of 270 to 290 degrees and a pressure of 200 to 13.3 Pa. An apparatus for continuously producing polyester. Used in the final reaction stage of the process for producing a high molecular weight polyester from an aromatic dicarboxylic acid or a derivative thereof and a glycol,
The horizontal cylindrical container body has an inlet and an outlet for the liquid to be treated at one end lower part and the other end lower part in the longitudinal direction respectively, has an outlet for volatile substances at the upper part of the body, and is close to the inside of the body in the longitudinal direction inside the body. The stirring rotor inside the main body is composed of a plurality of stirring blade blocks according to the viscosity of the processing liquid, and a stirring blade having no rotating shaft is provided at the center of the stirring rotor. A reactor for continuous production of polyester, comprising: Used in the final reaction stage of the process for producing a high molecular weight polyester from an aromatic dicarboxylic acid or a derivative thereof and a glycol,
The substantially horizontal cylindrical container body has an inlet and an outlet for the liquid to be treated at one end lower part and the other end lower part in the longitudinal direction, respectively, has an outlet for volatile matter at the upper part of the main body, and has the main body in the longitudinal direction inside the main body. The stirring rotor inside the main body of the apparatus provided with the stirring rotor rotating close to the inside is constituted by a plurality of stirring blade blocks according to the viscosity of the processing liquid, and the stirring rotor having no rotating shaft at the center of the stirring rotor. Wherein the outer diameter of an end plate connecting the power transmission shafts at both ends and the stirring rotor is smaller than the outer diameter of the stirring rotor. The reactor according to claim 10, wherein a plurality of stirring blocks are provided on the inlet side for low-viscosity stirring, and each of the stirring blocks has a hollow disk provided at both ends and an outer peripheral portion of the disk. The bucket is provided with a bucket portion for scooping up the processing liquid by the oyster plate, and a hollow thin disk placed close to the inner peripheral end surface of the oyster plate. A reactor for continuous production of polyester, characterized by having a structure in which a liquid film is poured between hollow thin disks and a liquid film is formed between the thin disks. 12. The reactor according to claim 11, wherein the bucket portion has a hole or a small gap through which the processing liquid flows out at a horizontal joint portion of the bottom-side oyster plate. 11. The reactor according to claim 10, wherein a plurality of connected stirring blocks are provided for medium viscosity stirring, and each of the stirring blocks is provided with a hollow disk provided at both ends and a plurality of radial blocks on an outer peripheral portion of the disk. And a hollow thin plate having the same size as the outer circumference of a plurality of discs provided between the hollow discs, and a plurality of small circular holes are formed in the thin plate. For continuous production of polyester. 11. The reactor according to claim 10, wherein a stirring block is provided for high-viscosity stirring, and the stirring block comprises a plurality of wheel-shaped disks with an oyster plate arranged in a horizontal direction. A reactor for continuous production of polyester, wherein the mounting positions of the polyesters are alternately set. In the reactor according to claim 10, the outer diameter of the high-viscosity side supporting member connecting the stirring rotor portion is smaller than the outer diameter of the stirring rotor, and the inner wall surface of the tank is provided between the side surface of the supporting member and the inner end surface of the tank. A reactor for continuous production of polyester, which is provided with an oscillating blade which is arranged so as to rotate in close proximity and send out a processing liquid attached near a wall surface to the outer periphery of the tank by rotating. In the reactor according to claim 10, an inlet and an outlet for the liquid to be treated are provided at one end and the other end of the substantially horizontal cylindrical container main body in the longitudinal direction, respectively, and an outlet for volatiles is provided at an upper part of the main body, A stirring rotor that rotates close to the inside of the main body in the longitudinal direction inside the main body is provided, and the stirring rotor is configured with a plurality of stirring blade blocks according to the viscosity of the processing liquid, and a stirring blade block on the high viscosity side is provided. The outer diameter plate of the end plate connecting the outer peripheral plate between each of the partitioning disks constituting the end plate connecting the power transmission shaft on the end side and the stirring rotor unit in the stirring rotor having no rotating shaft at the center of the stirring rotor is adjusted. A reactor for continuous production of polyester characterized in that the diameter is smaller than the outer diameter of the stirring rotor. Used in an intermediate reaction stage of a process for producing a high-molecular-weight polyester from an aromatic dicarboxylic acid or a derivative thereof and a glycol,
A substantially vertical cylindrical container main body has an inlet and an outlet for the liquid to be treated at one lower side and lower center in the longitudinal direction of the main body, a volatile substance outlet at the upper part of the main body, and the outer side of the main body is covered with a heat medium jacket. In the apparatus, a heat exchange part is provided in the lower part of the main body, a retention part having a spiral baffle plate for holding the liquid to be treated and moving upward from the bottom in the middle part of the main body is provided, and gas-liquid separation is provided in the upper part of the main body. For continuous production of polyester, characterized in that a space for the liquid is provided, and a downcomer pipe is provided in a vertical direction in the center of the main body so that the liquid to be treated flows down in a thin film. Used in the first reaction stage of the process for producing a high molecular weight polyester from an aromatic dicarboxylic acid or a derivative thereof and a glycol,
An inlet and an outlet for the liquid to be treated are provided in a vertical cylindrical container main body, a vapor pipe for discharging vapor is provided at an upper portion, the cylindrical container main body is covered with a heat medium jacket, and the outside of the pipe is provided inside the cylindrical container main body. In a natural circulation type evaporator having a built-in multi-tube heat exchanger in which a liquid to be treated rises inside the tube, the inner wall of the cylindrical container body and the outer wall of the shell of the multi-tube heat exchanger are heated by a heat medium. The average velocity of the liquid to be treated flowing down by natural convection between the pipes is smaller than the average flow velocity of the liquid to be treated rising inside the tubes of the multitubular heat exchanger, and the lower shell portion outside the multitubular heat exchanger. A natural circulation evaporator characterized by having a run-in space for allowing the liquid to be circulated internally to flow uniformly into the evaporator.

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