Connection Structure of Indirect Heating Device

Abstract

To easily prevent occurrence of an adverse effect caused by the thermal expansion of a connection unit of a simple configuration, disposed between indirect heaters.SOLUTION: The connection structure connecting indirect heaters consisting of a thin film indirect heater 1 extended in the horizontal direction and provided with a first raw material feed port 3a on one end and a first raw material discharge port 3b on the other end to indirectly heat a liquid raw material supplied from the first raw material feed port 3a and to subsequently discharge the same from the first raw material discharge port 3b, and of a screw type indirect heater 2 provided with a second raw material feed port 7a for the liquid raw material discharged from the first raw material discharge port 3b to be supplied therethrough, disposed below the thin film indirect heater 1 to communicate with the first raw material discharge port 3b and provided with a second raw material discharge port 7b on the other end, to indirectly heat the liquid raw material supplied from second raw material feed port 7a to subsequently discharge the solid component from the second raw material discharge port 7b, is characterized in that the first raw material discharge port 3b and the second raw material feed port 7a are connected by a discharge chute 20 that can change its vertical length by sliding in the vertical direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a connection structure of an indirect heating device for indirectly heating a liquid raw material.

Background Art

[0002] Conventionally, a drum that extends horizontally, has a raw material supply hole on one end side, and a raw material discharge hole on the other end side, a rotating shaft that rotates inside the drum, and a plurality of stirring blades that are provided on the rotating shaft and press the liquid raw material supplied from the raw material supply hole against the heated inner surface of the drum in a thin film state and dry it, and a solvent recovery hole that is provided above the drum and recovers the solvent evaporated from the liquid raw material in the drum while contacting the liquid raw material splashed up by the stirring blades are known (see, for example, Patent Documents 1 and 2). The supply port of a screw-type indirect heating device is hermetically connected to the raw material discharge hole of this thin film type indirect heating device.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the inventions of Patent Documents 1 and 2, the liquid raw material is heated and indirectly heated by a thin film type indirect heating device and a screw type indirect heating device, respectively.

[0005] Therefore, when thermal expansion occurs in the portion connecting the two, a structure for absorbing the thermal expansion (for example, a bellows structure) is required, or it is necessary to adjust the gap by a shim according to the heating temperature.

[0006] On the one hand, if the connecting part has a bellows structure, dead space will occur, and there is a risk that the internal fluid will be blocked in that part. In addition, adjusting the gap with a shim according to the heating temperature is a very troublesome operation.

[0007] The present invention has been made in view of such points, and an object thereof is to prevent the occurrence of adverse effects due to thermal expansion of the connecting part easily with a simple configuration.

Means for Solving the Problems

[0008] In order to achieve the above object, in the present invention, an upper and a lower indirect heating device are connected by a discharge chute that can slide in the vertical direction.

[0009] Specifically, in the first invention, A first indirect heating device that extends in the horizontal direction, has a first raw material supply hole on one end side, and a first raw material discharge hole on the other end side, and indirectly heats the liquid raw material supplied from the first raw material supply hole and discharges it from the first raw material discharge hole; A second indirect heating device provided below the first indirect heating device, having a second raw material supply hole communicating with the first raw material discharge hole and supplied with the liquid raw material discharged from the first raw material discharge hole, and having a second raw material discharge hole on the other end side, and indirectly heating the liquid raw material supplied from the second raw material supply hole and discharging the solid content from the second raw material discharge hole; The first raw material discharge hole and the second raw material supply hole are connected by a discharge chute that can slide in the vertical direction to change the length in the vertical direction, The discharge chute A first cylindrical portion in which the first raw material discharge hole is formed; A second cylindrical portion in which the second raw material supply hole having an inner diameter larger than the outer diameter of the first cylindrical portion is formed, and which is slidably fitted to the first cylindrical portion; A sealing member provided between the outer peripheral surface of the first cylindrical portion and the inner peripheral surface of the second cylindrical portion to seal the gap between the outer peripheral surface of the first cylindrical portion and the inner peripheral surface of the second cylindrical portion; Falling said The liquid raw material is in the second cylindrical portionupper It is configured so as not to collide with the end face.

[0010] According to the above configuration, even if dimensional changes in the vertical direction occur due to thermal expansion at the joint of each indirect heating device, the discharge chute can slide to absorb the dimensional changes, so there is no need to adopt a general metal expansion pipe such as a bellows structure or adjust the gap with a shim or the like. For this reason, the length of the discharge chute can be made shorter than that of a general metal expansion pipe, and the dead space at the connection part can be reduced, so that blockage of the internal fluid is suppressed. In addition, extra operations such as gap adjustment by shims due to the operating temperature become unnecessary, and the operation and stop operations of the indirect heating device can be simplified. 。

[0011] also By the relative sliding movement of the first cylindrical portion and the second cylindrical portion, dimensional changes in the vertical direction can be easily absorbed.

[0012] The 2 invention, in the 1 invention, The sealing member is an O-ring fitted into at least one of the first cylindrical portion and the second cylindrical portion.

[0013] According to the above configuration, the gap between the first cylindrical portion and the second cylindrical portion can be sealed with an extremely simple configuration.

[0014] The 3 invention, in the 2 invention, At least one of the first cylindrical portion and the second cylindrical portion is configured to be able to heat the liquid shape raw material by internally circulating a heat medium passing through the inside of the first indirect heating device or the second indirect heating device. .

[0015] According to the above configuration, temperature adjustment can also be performed in the discharge chute, so more reliable temperature adjustment of the indirect heating device can be performed.

Advantages of the Invention

[0016] As described above, according to the present invention, the first raw material discharge hole of the first indirect heating device and the second raw material supply hole of the second indirect heating device are connected by a discharge chute that can slide in the vertical direction to change the length in the vertical direction. Therefore, there is no need to provide a bellows structure, nor is it necessary to adjust the gap with a shim, and it is possible to easily prevent the occurrence of adverse effects due to thermal expansion of the connection part with a simple configuration.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0018] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0019] -Configuration of the Thin Film Type Indirect Heating Device and the Screw Type Indirect Heating Device- FIG. 1 shows a thin film type indirect heating device 1 as the first indirect heating device according to an embodiment of the present invention and a screw type indirect heating device 2 as the second indirect heating device connected to the thin film type indirect heating device 1. In FIG. 1, for easy viewing, the thin film type indirect heating device 1 and the screw type indirect heating device 2 are drawn as extending in parallel, but they may intersect perpendicularly in a plan view.

[0020] The thin-film indirect heating device 1 is a so-called horizontal thin-film evaporator and includes a hollow drum 3 extending in the horizontal direction (lateral direction). A first raw material supply hole 3a for supplying a liquid raw material is formed on the lower surface of one end side of the drum 3. A first raw material discharge hole 3b for discharging the raw material in which the solvent has evaporated to some extent and the viscosity has increased is provided on the lower surface of the other end side of the drum 3. A first jacket 4 through which a heat medium 15 such as steam, hot water, or oil circulates is provided on the outer periphery of the drum 3. Inside the drum 3, a rotating shaft 5 extending horizontally and rotated by a motor 5a is provided. The drum 3 and the rotating shaft 5 do not necessarily have to be completely horizontal and may be slightly inclined.

[0021] A plurality of spatula-shaped stirring blades 6 are provided on the outer periphery of the rotating shaft 5 at predetermined intervals. Although detailed description is omitted, for example, a pair of stirring blades 6 are provided at intervals of 180 degrees in the circumferential direction, and another pair of stirring blades 6, which are also spaced 180 degrees apart from this pair of stirring blades 6, are arranged at substantially equal intervals in the axial direction and shifted 90 degrees in the circumferential direction. By making the axial interval between the pair of stirring blades 6 equal to the length of the tip of the stirring blade 6, the liquid raw material supplied from the liquid first raw material supply hole 3a is pressed against the inner surface of the drum 3 heated by the first jacket 4 in a thin film state and dried while heading toward the first raw material discharge hole 3b. The pressed liquid raw material has its solvent vaporized and its viscosity gradually increases, and it is sent from the first raw material discharge hole 3b to the screw-type indirect heating device 2.

[0022] On the one hand, the screw-type indirect heating device 2 has a hollow casing 7 extending in the horizontal direction, and a second jacket 8 through which the heat medium 15 flows is provided on the outer periphery of the casing 7. On the upper side of one end of the casing 7, a second raw material supply hole 7a that is hermetically connected to the first raw material discharge hole 3b is provided. Inside the casing 7, a pair of horizontally extending hollow screws 9 are provided, and the heat medium 15 can also flow through these hollow screws 9. The pair of hollow screws 9 are arranged to mesh with each other, and the clearance with the inner surface of the lower part of the casing 7 is set small, and it has a self-cleaning function.

[0023] Then, by passing the heat medium 15 such as steam through the second jacket 8 and the inside of each hollow screw 9 and rotating the pair of hollow screws 9 in opposite directions to each other, the liquid raw material supplied from the second raw material supply hole 7a of the casing 7 is transferred by the hollow screw 9 toward the second raw material discharge hole 7b, and the liquid raw material is indirectly heated by conduction heating from the casing 7 and the hollow screw 9, and the solid content in the liquid raw material is discharged from the second raw material discharge hole 7b.

[0024] On the other hand, a solvent recovery hole 10 is provided above the drum 3. A solvent recovery pipe 11 is provided upward from this solvent recovery hole 10, and this solvent recovery pipe 11 is connected to a vacuum pump via a condenser (not shown). By driving this vacuum pump, the inside of the drum 3 and the casing 7 is made to be in a negative pressure state. For this reason, the gas containing the solvent vaporized inside the casing 7 flows toward the second raw material supply hole 7a as shown by the white arrow in FIG. 1, flows into the drum 3 from the first raw material discharge hole 3b, merges with the gas containing the solvent vaporized inside the drum 3, and is sucked into the solvent recovery hole 10.

[0025] The solvent recovery pipe 11 is made of, for example, a pipe member having a rectangular cross-section, and a pair of baffle plates 12 in the shape of a rectangular plate are provided on the lower end side thereof. These baffle plates 12 are made of, for example, stainless steel plates, are provided at intervals vertically so as to face each other, and the facing tips are each inclined downward.

[0026] Furthermore, a demister 13 through which the gas containing the evaporated solvent can pass may be disposed on the downstream side (upper side) of the two baffle plates 12. This demister 13 is composed of, for example, an aggregate in the form of a mesh of thin metal wires, and the lower surface is supported by, for example, a stainless steel punching plate 14.

[0027] And as a feature of the present embodiment, the first raw material discharge hole 3b and the second raw material supply hole 7a are connected by a discharge chute 20 that can slide in the vertical direction to change the length in the vertical direction.

[0028] Specifically, as shown in FIG. 2, this discharge chute 20 includes a cylindrical first cylindrical portion 21 in which the first raw material discharge hole 3b is formed, and a second cylindrical portion 22 having a circular cross-section in which the second raw material supply hole 7a is formed and that is slidably fitted to the first cylindrical portion 21 and has an inner diameter slightly larger than the outer diameter of the first cylindrical portion 21.

[0029] For example, the first cylindrical portion 21 is made of a SUS316L cylindrical tube with an inner diameter of about 365 mm, an outer diameter of 390 mm, and a wall thickness of 12.5 mm, and the second cylindrical portion 22 is made of a SUS316L cylindrical tube with an inner diameter of about 390 mm, an outer diameter of 415 mm, and a wall thickness of 12.5 mm. The linear expansion coefficient of SUS316L is 16.5×10-6 (1 / °C). The materials of the first cylindrical portion 21 and the second cylindrical portion 22 may also be SUS304, SUS316, etc. For example, the upper and lower intermediate portions of the first cylindrical portion 21 and the second cylindrical portion 22 may be divided and the divided portions may be joined to each other by flanges.

[0030] Between the first cylindrical portion 21 and the second cylindrical portion 22, an O-ring 24 is provided as a sealing member for sealing the gap between the first cylindrical portion 21 and the second cylindrical portion 22. This O-ring 24 is fitted into a sealing groove portion 23 that is continuously recessed in the circumferential direction on the outer periphery of the first cylindrical portion 21 with a small diameter. For example, a sealing groove portion 23 having a rectangular cross-section with a depth of about 5 mm is provided on the lower side of the outer periphery of the first cylindrical portion 21, and an O-ring 24 with an outer diameter of the cross-section of 8.4 mm is fitted into this sealing groove portion 23. This O-ring 24 can absorb thermal expansion or contraction of about 3 mm in the radial direction. The material of the O-ring 24 is not particularly limited, but it is composed of vinylidene fluoride-based (FKM), tetrafluoroethylene-perfluorovinyl ether-based (FFKM), polytetrafluoroethylene (PTFE), etc., which are excellent in heat resistance, chemical resistance, etc.

[0031] Note that the inner diameter of the first cylindrical portion 21 may be larger than the outer diameter of the second cylindrical portion 22. In this case, the O-ring 24 may be fitted into the sealing groove portion 23 provided on the outer periphery of the second cylindrical portion 22, and the first cylindrical portion 21 may be inserted from the outside thereof.

[0032] The vertical lengths of the first cylindrical portion 21 and the second cylindrical portion 22 are shorter than those of the conventional ones. For example, the length of the first cylindrical portion 21 is 35 mm and the length of the second cylindrical portion 22 is 84 mm.

[0033] -Operation of the thin-film type indirect heating device and the screw type indirect heating device- Next, the case where the thin-film type indirect heating device 1 and the screw type indirect heating device 2 are operated will be described.

[0034] First, a motor 5a or the like is driven to rotate the rotating shaft 5 and the hollow screw 9. At this time, a heat medium 15 such as steam or hot water is circulated through the first jackets 4, 8 and the hollow screw 9 to heat it to a predetermined temperature.

[0035] Next, a liquid raw material is supplied from the first raw material supply hole 3a. The liquid shapeThe raw material is, for example, a thermoplastic resin, and its viscosity is, for example, 1000 mPa·s. The liquid raw material supplied to the first raw material supply hole 3a contains a considerable amount of solvent immediately after supply and is vigorously bounced up by the stirring blade 6. Then, the gas containing the solvent evaporated from the liquid raw material in the casing 7 and the drum 3 contacts the liquid raw material bounced up by the stirring blade 6, so that the powdered raw material in the gas is incorporated into the liquid raw material. The solvent is not particularly limited.

[0036] The liquid raw material incorporating the powder material collides with one of the pair of baffle plates 12 and falls into the drum 3 due to its own weight.

[0037] And even if the gas passing through the pair of baffle plates 12 contains the liquid raw material in the form of droplets, when the gas passes through the demister 13, it collides with the thin metal wires, and due to the wettability of the metal wires and the capillary phenomenon of the gaps between the wires, they gather and flow down and fall.

[0038] Then, the gas containing the solvent from which the powdered raw material and the liquid raw material have been removed is efficiently recovered and cooled by a cooling condenser.

[0039] During such operation, at the discharge chute 20 which is the connecting part of the thin-film type indirect heating device 1 and the screw type indirect heating device 2, the liquid shape raw material and the solvent gas flow under a negative pressure of -0.5 to 0 kPaG. The temperature rises up to 250°C at maximum. For this reason, the first cylindrical part 21 and the second cylindrical part 22 are heated in the vertical direction respectively, and the first cylindrical part 21 and the second cylindrical part 22 together extend by, for example, about 3.5 mm at maximum.

[0040] However, in this embodiment, even if dimensional changes in the vertical direction occur due to thermal expansion in each of the indirect heating devices 1 and 2, the discharge chute 20 can slide to absorb the dimensional changes. Therefore, it is not necessary to employ a general metal expansion pipe such as a bellows structure or to adjust the gap using a shim or the like. For this reason, the length of the discharge chute 20 can be made shorter than that of a general metal expansion pipe, the dead space of the connecting portion can be reduced, and blockage of the internal fluid can be suppressed. In addition, extra operations such as gap adjustment using a shim according to the operating temperature become unnecessary, and the operation and stop operations of the indirect heating device can be simplified.

[0041] Particularly in this embodiment, the cylindrical first cylindrical portion 21 and the cylindrical second cylindrical portion 22 can slide relative to each other vertically, so that dimensional changes in the vertical direction can be easily absorbed.

[0042] Furthermore, in this embodiment, a sealing groove portion 23 is formed, and the gap between the first cylindrical portion 21 and the second cylindrical portion 22 can be sealed with a very simple configuration in which an O-ring 24 is fitted into the sealing groove portion 23.

[0043] Therefore, according to the thin film type indirect heating device 1 according to this embodiment, since the first raw material discharge hole 3b and the second raw material supply hole 7a are connected by a discharge chute 20 that can slide vertically to change the length in the vertical direction, it is not necessary to provide a bellows structure, nor is it necessary to adjust the gap using a shim or the like. With a simple configuration, it is possible to easily prevent the occurrence of adverse effects due to thermal expansion of the connecting portion.

[0044] (Other Embodiments) The present invention may be configured as follows with respect to the above embodiment.

[0045] That is, in the above embodiment, the O-ring 24 having a circular cross-section is used as the sealing member. However, as long as sealing between the first cylindrical portion 21 and the second cylindrical portion 22 is possible and the vertical sliding movement between the first cylindrical portion 21 and the second cylindrical portion 22 is not hindered, it may be configured with other sealing members such as an X-ring.

[0046] In the above embodiment, the first cylindrical portion 21 and the second cylindrical portion 22 are constituted by simple metal pipes. However, a jacket is provided on at least one of them, and a heat medium passing through the inside of the thin film type indirect heating device 1 or the screw type indirect heating device 2 is circulated inside, so that the liquid passing through the discharge chute 20 shape raw material may be configured to be heatable. By doing so, temperature adjustment can also be performed in the discharge chute 20, so that more reliable temperature adjustment of the indirect heating device can be performed, which is advantageous.

[0047] In the above embodiment, the liquid shape The indirect heating device for the purpose of drying the raw material was targeted, but other raw materials may be kneaded and reacted. In that case as well, dimensional changes due to temperature changes (not only in the vertical direction but also in the horizontal direction) can be absorbed.

[0048] Note that the above embodiments are essentially preferred examples and are not intended to limit the scope of the present invention, its applications, or uses.

Explanation of Reference Numerals

[0049] 1 Thin film type indirect heating device (first indirect heating device) 2 Screw type indirect heating device (second indirect heating device) 3 Drum 3a First raw material supply hole 3b First raw material discharge hole 4 First jacket 5 Rotating shaft 5a Motor 6 Stirring blade 7 Casing 7a Second raw material supply hole 7b Second raw material discharge hole 8 Second jacket 9 Hollow screw 10 Solvent recovery hole 11 Solvent recovery pipe 12 Baffle plate 13 Demister 14 Punching plate 15 Heat medium 20 Discharge chute 21 First cylindrical part 22 Second cylindrical part 23 Sealing groove part 24 O-ring

Claims

1. A first indirect heating device that extends horizontally, has a first raw material supply hole on one end side, and a first raw material discharge hole on the other end side, and indirectly heats the liquid raw material supplied from the first raw material supply hole and discharges it from the first raw material discharge hole; A second indirect heating device provided below the first indirect heating device, communicating with the first raw material discharge hole, having a second raw material supply hole to which the liquid raw material discharged from the first raw material discharge hole is supplied, and a second raw material discharge hole on the other end side, and indirectly heating the liquid raw material supplied from the second raw material supply hole and discharging the solid content from the second raw material discharge hole; The first raw material discharge hole and the second raw material supply hole are connected by a discharge chute that can slide in the vertical direction to change the length in the vertical direction; The discharge chute is A first cylindrical portion in which the first raw material discharge hole is formed; A second cylindrical portion in which the second raw material supply hole having an inner diameter larger than the outer diameter of the first cylindrical portion is formed and that is slidably fitted to the first cylindrical portion; A sealing member provided between the outer peripheral surface of the first cylindrical portion and the inner peripheral surface of the second cylindrical portion and sealing the gap between the outer peripheral surface of the first cylindrical portion and the inner peripheral surface of the second cylindrical portion; The liquid raw material that falls is configured not to collide with the upper end surface of the second cylindrical portion. A connection structure of an indirect heating device, characterized by the above.

2. The connection structure of the indirect heating device according to claim 1, characterized in that the sealing member is an O-ring fitted into at least one of the first cylindrical portion and the second cylindrical portion.

3. The connection structure of the indirect heating device according to claim 2, characterized in that at least one of the first cylindrical portion and the second cylindrical portion is configured to be able to heat the liquid raw material by internally circulating a heat medium that passes through the inside of the first indirect heating device or the second indirect heating device. The connection structure of the indirect heating device according to claim 2, characterized in that at least one of the first cylindrical portion and the second cylindrical portion is configured to be able to heat the liquid raw material by internally circulating a heat medium that passes through the inside of the first indirect heating device or the second indirect heating device. A connection structure of an indirect heating device, characterized by the above.

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