JP2011056356A - Horizontal reactor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a horizontal reactor which need not be stirred strongly, even a material to be stirred belongs to a high viscosity range, and can enhance reaction velocity/reaction efficiency and further, as a result, can produce a polymer compound with successful quality as an end product. <P>SOLUTION: This horizontal reactor has the following elements (A) to (E): (A) it is of a cylindrical type, (B) it has a reactive liquid inlet and a reactive liquid outlet at both end parts of the reactor or near the both end parts respectively, (C) it has freely rotating end part discs, each opposed to the both internal end parts of the reactor and (D) it has a plurality of opening discs which are arranged between the end part discs, and also, have each an opening formed in the center, and (E) it has stirring blades fitted between the end part disk and the opening disc and also between the opening discs, arranged in proximity to or in close contact with the inner circumferential wall surface of the reactor in the longitudinal direction of the reactor, and having a through hole. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a horizontal reactor. More specifically, even if the object is in a high viscosity region, the reaction rate and reaction efficiency can be improved without requiring intense stirring, resulting in the quality of the polymer compound finally obtained. The present invention relates to a horizontal reaction apparatus having a good temperature.

  Polymer compounds such as polyester, polyamide and polycarbonate, especially aromatic polyesters typified by polyethylene terephthalate and polybutylene terephthalate, and aliphatic polyesters typified by polylactic acid have various physical and chemical properties. It is widely used for applications. In particular, polyester is excellent in mechanical properties such as strength and elastic modulus, heat resistance, and the like, and is therefore widely used as industrial fibers such as clothing and tire cords, or as films and engineering plastics.

In general, a direct polymerization method or a transesterification method is used as a method for producing polyester used for such various applications.
Here, the former direct polymerization method is a method in which a polyester precursor is formed by directly esterifying an acid component and a diol component, and then the polyester precursor is polycondensed under reduced pressure to produce a polyester. . On the other hand, the latter transesterification method is a method in which a lower alkyl ester of an acid component and a diol are transesterified to form a polyester precursor, and then the polyester precursor is polycondensed under reduced pressure.

  In the case of polymerization of such a polyester, conventionally, a batch method has been used in many cases. However, in recent years, taking advantage of the scale, and in order to produce a polyester at a low cost, switching to a continuous method has been promoted. . This is because the merits such as yield reduction, quality improvement, uniformity of polymerization degree, improvement in operability, etc. are extremely large by adopting the continuous method.

  In general, most of the production methods by continuous polymerization of polyester are performed by a process in which a plurality of transesterification reaction tanks or esterification reaction tanks and polycondensation reaction tanks are combined. For example, a raw material is supplied to a transesterification reaction tank or an esterification reaction tank to produce a monomer, and the obtained monomer is supplied to an initial polycondensation reaction tank and reacted under reduced pressure to produce a low polymer. Is further supplied to a polycondensation reaction tank to produce an intermediate polymer and a high polymer under reduced pressure.

  In such a polycondensation reaction tank, many methods for obtaining a higher reaction rate have been proposed and put into practical use. For example, as one of such conventional methods, a thin film reaction vessel is used in which a reaction product is made into a thin film layer for the purpose of quickly separating and removing by-products such as glycols in a polyester polycondensation reaction. In some cases, the reaction vessel is used or the reaction product can be easily evaporated by enlarging the free surface of the reaction product by vigorous stirring.

  As such a reaction device, a vertical reaction device of a wet wall type or a screw method, a horizontal reaction device of a uniaxial or biaxial method is generally used, and a large free surface of the reactant can be taken. There are also many commercially available reactors that take stirring into account, but these reactors require intense stirring, which increases the equipment costs and consumes a lot of energy. Have a problem.

Moreover, due to the reaction associated with intense stirring, the resulting reaction product has a problem that the degree of polymerization is likely to occur and the quality of the resulting polyester is deteriorated. Furthermore, there is a problem that the quality of the reaction product is also deteriorated due to the deterioration polymer due to the insufficient renewal of the polymer or the like staying in the gas phase for a long time being mixed.
As used herein, the term “horizontal reactor” refers to a “reactor provided such that the central axis direction of the rotation axis of a stirring blade provided in the reactor is substantially parallel to a horizontal plane”. To do.

  In order to solve such a problem, by using a horizontal reaction apparatus as proposed in Japanese Patent Publication No. 40-3964, the reaction solution is stirred up by stirring, and then most of the reaction solution thus stirred up is removed. By dropping it, a free surface of a new reactant is constantly formed, and the reaction is performed in a very short time. In this horizontal reactor, the stirring shafts for holding the stirring blades are provided only at both ends of the tank, thereby eliminating the stirring shaft from the intermediate portion inside the reactor.

Further, the reaction apparatus includes (1) the agitation blade opposed to a large part of the inner peripheral wall surface of the reaction apparatus with a small gap, and (2) two or more rotating together with the agitation blade. Is provided with a partition plate having an opening at the center thereof for partitioning the inside of the reactor.
According to the reaction apparatus, the inner peripheral wall surface of the reaction apparatus is constantly updated with new reaction liquid, so that heat transfer to the reaction liquid is good, and the reaction liquid adheres to the inner peripheral wall surface for a long time. Since the stirring shaft is not provided in the middle part of the reaction apparatus, there is a great advantage that no dumped reaction mass is generated around the stirring shaft.

However, in the reaction apparatus, no consideration is given to the form of the liquid film of the reactant falling from the stirring blade, and any contrivance has been made for controlling the free surface of the falling liquid film. Absent. For this reason, in this reaction apparatus, there is a limit to the ability to form such a free surface of the liquid film, and it has been extremely difficult to further increase the reaction efficiency.
In order to solve this problem, along the falling edge of the stirring blade from which the reaction liquid starts to fall from the stirring blade, the position can come into contact with at least a part of the falling reaction liquid in substantially parallel to the falling edge. It has been proposed to provide free surface forming members provided in a double row or a single row (see Patent Document 2).

  According to this method, the ability to form a free surface can be greatly improved. However, when the content of interest is in a high viscosity region (for example, 300 Pa · S to 3000 Pa · S), there is a new problem that it is extremely difficult to sufficiently ensure the formation of a free surface by the reaction liquid. Occurred.

Japanese Patent Publication No. 40-3964 Japanese Patent No. 3602958

  The object of the present invention is to improve the reaction rate and reaction efficiency without requiring intense stirring even if the object is in a high viscosity region, and as a result, the polymer compound finally obtained It is to provide a horizontal reactor having good quality.

The present inventor has reached the present invention as a result of intensive studies in view of the above prior art.
That is, the object of the present invention is to
This is achieved by a horizontal reactor comprising the following elements (A) to (E).
(A) It must be cylindrical.
(B) The reaction solution has an inlet and an outlet at both ends or in the vicinity of both ends.
(C) It has an end disk which can rotate freely opposite to both ends inside the reactor.
(D) It has a plurality of opening discs arranged between the end discs and having an opening at the center thereof.
(E) It is provided between the end disk and the opening disk and between the opening disks, and is provided close to or in close contact with the inner peripheral wall surface of the reaction apparatus along the longitudinal direction of the reaction apparatus. It has a stirring blade having.

According to the present invention, even if the object is in a high viscosity region, the reaction rate and reaction efficiency can be improved without requiring intense stirring, and as a result, the polymer compound finally obtained A horizontal reactor having good quality can be provided.
Further, the horizontal reactor of the present invention is not only used as a polymer polycondensation reaction device, but also as a device for removing low molecular weight substances from the target polymer, specifically as a device for delactide from polylactic acid. Can also be suitably used.

It is side surface sectional drawing which illustrated the horizontal reactor for implementing this invention. It is side surface sectional drawing which illustrated the conventional horizontal reaction apparatus. (A) shows the front view of the opening disc of this invention, (b) is the schematic diagram which showed the mode of the horizontal cross-section of the horizontal reactor during operation, and the rotation direction is counterclockwise. (C) is a front view of an open disc of a conventional horizontal apparatus, (d) is a schematic view showing a cross section of the horizontal reactor during operation, and the rotation direction is counterclockwise.

Hereinafter, embodiments of the present invention will be described in detail and specifically with reference to the drawings. FIG. 1 is a side cross-sectional view illustrating a horizontal reactor for carrying out the present invention.
In this figure, 1 is a horizontal reaction apparatus main body, 2 is a reaction liquid inlet, and 3 is a reaction liquid outlet, which are provided at or near both ends of the reaction apparatus 1 as shown. Reference numerals 4 and 5 denote shafts provided at both ends of the reaction apparatus 1. A vapor outlet 6 opens above the outer shell of the reactor and also serves as a suction port for maintaining the inside of the reactor at a reduced pressure. Reference numeral 7 denotes an inner peripheral wall surface of the reaction apparatus 1, and if necessary, projections can be provided on the inner peripheral wall surface 7 so as not to interfere with the stirring blade 10. Reference numerals 8 and 9 denote end disks, which are fixed to the shafts 4 and 5. The end disks 8 and 9 can be rotated by driving the shafts 4 and 5 with the power of a driving device (not shown). Reference numeral 10 denotes a stirring blade provided close to or in close contact with the longitudinal direction of the inner peripheral wall surface 7.

  Reference numeral 11 denotes an opening disk, and the opening disk 11 is connected and fixed at a predetermined interval in the longitudinal direction by a stirring blade 10 and has an opening at the center thereof. Has the role of partitioning the room. Reference numeral 12 denotes a through hole which is a feature of the present invention, and the through hole 12 is opened at an arbitrary place, an arbitrary size, and an arbitrary number of stirring blades 10.

Here, the conditions such as the number, shape, and size of the stirring blades and the through holes may be appropriately selected depending on the operating conditions.
If the area of the through-hole is too small, depending on the viscosity of the contents, there may be no effect due to the formation of the through-hole, but one area of the through-hole is 10 cm ² or more, preferably 20 cm ² or more. For example, even if the content is 3000 Pa · S, it can be dealt with. When the shape of the through hole is circular, the diameter is 4 cm or more, preferably 5 cm or more.

Further, the through-hole, although depending on the material of the stirring blade, is 70 on the basis of the length in the width direction of the stirring blade (the length from the blade tip of the stirring blade to the inner peripheral wall close (close) end of the stirring blade). If the size is up to about%, it can be set without any problem.
In addition, since the melt viscosity of the reaction solution also changes from the reactor inlet to the outlet, the through hole area may be increased accordingly in accordance with the change.
Below, the effect by this through-hole installation is demonstrated concretely using FIG. 3 and FIG.

  In FIG. 3, (a) shows a front view of the open disc of the present invention, and (b) is a schematic diagram showing a cross section of the horizontal reactor of the present invention during operation. In addition, the rotation direction of the opening disc during operation is counterclockwise.

  In FIG. 4, (c) is a front view of an open disc of a conventional horizontal apparatus, and (d) is a schematic view showing a cross-section of a conventional horizontal reactor during operation. Note that the direction of rotation of the opening disk during operation is counterclockwise.

  In the conventional horizontal reaction apparatus, as shown in (d), when the viscosity of the polymer increases, as shown in 14, the polymer is difficult to fall from the stirring blade blade end, and the film-like free surface forming part Less. Further, even if the rotational speed of the stirring blade is slowed down to take time for the formation of a film-like free surface at the tip of the stirring blade, the problem of free surface formation per unit time / volume is delayed. .

  On the other hand, in the horizontal reactor of the present invention, as shown in (b) and 15, a hollow conical free surface is formed by the polymer dropped from the through hole. Therefore, as shown in FIG. 14, the polymer is less likely to fall from the tip of the stirring blade as in the conventional case, but can be sufficiently supplemented by the dropped polymer from the through hole, and thus the object has a high viscosity. Even in the region, the reaction rate and reaction efficiency can be improved without requiring intense stirring, and as a result, the quality of the finally obtained polymer compound is good, and a horizontal reactor is provided. be able to.

  This horizontal reaction apparatus has means (not shown) for heating to a predetermined temperature, and the reaction apparatus outer shell can be directly carried out by an electric heat source, or the production apparatus outer shell is shown in FIG. A double jacket structure is used, and a suitable heating medium, for example, a heating medium liquid such as barrel heat, or a heating medium vapor is used for heating, and a method for installing a heat transfer surface in the reaction chamber is used as appropriate. can do. The heating may be performed by dividing each reaction chamber and / or further dividing the reaction chamber divided by an open disk so that each of the divided regions can be heated independently, or heating two or more reaction chambers integrally. You can also Furthermore, if necessary, a circulating means having a heat exchanger provided inside or separately from the horizontal reactor of the present invention can be provided. As for the reaction pressure, it can of course be carried out under reduced pressure. However, the reaction pressure is not limited to reduced pressure, and the reaction can be carried out under an inert gas atmosphere even at atmospheric pressure or pressure higher than atmospheric pressure. Can do.

DESCRIPTION OF SYMBOLS 1 Horizontal reactor 2 Reaction liquid inlet 3 Reaction liquid outlet 4,5 Axis 6 Steam outlet 7 Inner peripheral wall surface 8,9 of reaction apparatus End disk 10 Stirring blade 11 Opening disk 12 Through hole 13 Polymer 14 Stirring blade blade end Film-shaped free surface forming part 15 due to falling polymer from the hollow conical free surface forming part due to falling polymer from the through hole

Claims (2)

A horizontal reactor comprising the following elements (A) to (E).
(A) It must be cylindrical.
(B) The reaction solution has an inlet and an outlet at both ends or in the vicinity of both ends.
(C) It has an end disk which can rotate freely opposite to both ends inside the reactor.
(D) It has a plurality of opening discs arranged between the end discs and having an opening at the center thereof.
(E) It is provided between the end disk and the opening disk and between the opening disks, and is provided close to or in close contact with the inner peripheral wall surface of the reaction apparatus along the longitudinal direction of the reaction apparatus. It has a stirring blade having.   The horizontal reactor according to claim 1, wherein the shape of the through hole is selected from a perfect circle, an ellipse, and a polygon.

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