JP2003193061A - Pyrolyzing oven for organic compound pyrolyzing equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pyrolyzing oven for organic compound components of simplified structure with improved heating efficiency, having the mechanism of heating wastes in an oxygen-blocked atmosphere. <P>SOLUTION: This pyrolyzing oven has the following structure and mechanism; an oven body 2 is constructed of a vertical cylindrical body, wastes charged via a port 3 on the top are heated by a heating coil 8 while being moved toward a discharge port 6 at the bottom by falling by the aid of their own weight to pyrolyze the organic compounds in the wastes. Since the wastes move downward by their own weight, they can be packed throughout the oven, improving the externally heating efficiency of the oven, further, because of no need of any feed mechanism for moving the wastes, the structure of the oven is simplified. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic compound decomposition treatment apparatus for treating plastic waste by thermal decomposition, and more particularly to a thermal decomposition furnace for heating an object to be treated.

[0002]

2. Description of the Related Art Waste materials have been conventionally treated mainly by incineration, but the incineration processing causes adverse effects on the environment such as air pollution and soil pollution due to the discharged materials. In particular, plastic waste has a problem of generating dioxins when incinerated. Therefore, as a waste treatment means for suppressing the generation of dioxins, a technology for thermally decomposing organic compounds has been developed, and it is expected to be put to practical use and spread in the future. In this thermal decomposition technique, an organic compound is heated in a low oxygen (air) or oxygen-free (collectively referred to as "oxygen blocking") atmosphere to decompose it into oil or gas. When an organic compound burns in the presence of oxygen, it becomes carbon dioxide, water vapor, and a residue, but plastics such as PVC containing chlorine generate dioxins when burned.
When air (oxygen) is blocked and pyrolyzed, the production of dioxins, which are oxygen-containing compounds, is suppressed.

As a thermal decomposition furnace for thermally decomposing plastic waste in an oxygen-shielded atmosphere, there are conventionally known a continuous processing system such as a rotary system, a screw system, and a batch processing system such as a crucible system. The rotary type is one in which a hollow cylindrical pyrolysis furnace (rotary kiln) arranged horizontally is heated from the outside while rotating, and the waste in the furnace replaced with an inert gas is pyrolyzed. 11-5
(See Japanese Patent No. 6542). In the screw type, the waste is heated from the outside while being pumped by a screw feeder in a hollow cylindrical furnace to thermally decompose the waste (see, for example, JP-A-9-59310).

[0004]

The conventional continuous thermal decomposition furnace is usually a horizontal type, and the thermal decomposition furnace is rotated (rotary type) or pressure fed by a screw feeder (screw type). The object to be processed is moved in the furnace in the axial direction. However, such a conventional pyrolysis furnace has the following problems. In the rotary type, since the material to be treated is sent by the rotation of the kiln body, the filling rate in the furnace cannot be increased, and in reality, more than half of the upper part of the furnace is a space and the thermal efficiency is low. Further, if a feeding mechanism such as a screw feeder is provided in the furnace, it is necessary to further reduce the filling rate in the furnace, and the apparatus becomes large in terms of throughput, which is difficult to apply. On the other hand, the batch type has low processing efficiency. Movable parts such as the rotation support part and screw feeder of the rotary kiln are heavily worn and maintenance is difficult. The horizontal type pyrolysis furnace has a large installation space and the equipment becomes large.

An object of the present invention is to address these problems and improve the thermal efficiency of a pyrolysis furnace for pyrolyzing organic compounds.
The purpose is to simplify the structure and reduce the installation space.

[0006]

In order to solve the above-mentioned problems, the present invention relates to a pyrolysis furnace of an organic compound decomposition treatment apparatus for thermally decomposing an organic compound in an oxygen-shielded atmosphere, in which a vertical hollow cylinder is used. The body is constructed so that the object to be treated introduced from the upper inlet is dropped by its own weight to be thermally decomposed while moving to the outlet at the bottom (claim 1).
According to the first aspect, the object to be processed moves downward due to its own weight drop, so that the object to be processed can be filled in the entire furnace, the thermal efficiency becomes high, and the feeding mechanism for the movement is unnecessary. Also,
Since it is placed vertically, the installation space is small.

In the first aspect, it is preferable that the furnace body is provided with a slope in the furnace wall so that the cross-section expands downward (claim 2). As a result, catching due to hanging on the shelf is suppressed, and the weight of the object is easily dropped, so that the object to be processed can be moved more smoothly.

In the present invention, it is preferable that the furnace body is made of a metal (including a non-magnetic material) or a magnetic material and is induction-heated by a heating coil arranged outside (claim 3). Conventionally, the heat of combustion of oil or gas or the resistance heat of an electric heater is often used to heat the object to be processed, but by using induction heating, fine temperature control is possible and thermal efficiency is also increased. .

According to a third aspect of the present invention, it is preferable that the furnace body has a rectangular cross section. In induction heating of a pyrolysis furnace, the furnace wall is first heated by Joule heat of an induction current, and then the object to be processed is heated by radiant heat from the furnace wall and heat transfer from an atmospheric gas. In that case, by making the cross-sectional shape of the furnace body rectangular, the surface area inside the furnace is large and the distance from the furnace wall to the object to be processed is short, so that the objects to be processed in the furnace can be made uniform in a short time. The temperature can be raised. As a result, it becomes possible to efficiently heat the object to be treated in the central portion of the furnace.

In claim 3, the magnetic penetration depth of the heating coil is preferably set within the thickness of the furnace wall (claim 5). As described above, the induced current needs to flow only in the furnace wall of the pyrolysis furnace, and for that purpose, the magnetic penetration depth should not exceed the plate thickness of the furnace wall. This prevents the magnetic flux from entering the inside of the pyrolysis furnace, makes it difficult to directly receive induction heating even when a magnetic material is present in the furnace, and improves the heating efficiency of the pyrolysis furnace.

In the first aspect of the present invention, it is preferable that a bottom is provided with a cutting device for discharging the object to be processed in a fixed amount (claim 6). In order to efficiently and smoothly take out the objects to be dropped in the furnace under its own weight, it is preferable to discharge them in batches in a semi-batch manner. In that case, it is preferable that the cutting device is provided with a pusher for laterally pushing the object in the furnace at a constant height (Claim 7). It is preferable that the object to be processed is pushed out by the turning motion of the swing arm (claim 8).

[0012]

1 shows an embodiment of the present invention, FIG. 1 (A) is a vertical sectional view of a pyrolysis furnace, and FIG. 1 (B) is a sectional view taken along line BB thereof. . In FIG. 1, a furnace body 2 of a pyrolysis furnace 1 is composed of a vertical hollow cylindrical body having a rectangular cross section,
It is made of magnetic material (steel plate). The material of the furnace body 2 may be a magnetic material, a metal (including a non-magnetic material), or any material that can be induction-heated. The illustrated furnace body 2 has a height of about 5 as an example.
m, front and rear width approximately 0.4 m, left and right width approximately 1 m, furnace wall plate thickness 25 mm
Is configured. The thermal decomposition furnace 1 is provided with an input port 3 for an object to be treated, and the input port 3 is connected to an input conveyor 4. Immediately below the charging port 3, the distribution plate 5a swings left and right to move the object to be processed in the long side direction of the furnace space (see FIG. 1).
A distribution mechanism 5 that distributes in (left and right direction of (B)) is provided. A discharge port 6 for the object to be treated is provided at the bottom of the thermal decomposition furnace 1, and a cutting device 7 for discharging the object (residue) after the thermal decomposition is provided at the outlet 6. Cutting device 7
Has a pusher 7b formed of a swing arm in an airtight housing 7a, and pushes the object to be processed quantitatively while swinging the pusher 7b between a solid line position and a chain line position in the drawing.

In the pyrolysis furnace 1, the furnace wall is induction-heated by the heating coil 8 arranged outside, and the object to be treated in the furnace is heated by radiant heat from the furnace wall and heat transfer from the atmospheric gas.
The magnetic penetration depth of the heating coil 8 is set within the plate thickness of the furnace body 2 so that only the furnace wall is induction-heated. Since the furnace body 2 has a rectangular cross section, the front and rear direction (Fig. 4 (A))
Radiation heat from the furnace wall with a small width (horizontal direction) is easy to reach the object to be processed in the center of the furnace.
The pyrolysis gas (exhaust gas) generated from the object to be treated is discharged through the exhaust gas pipe 9.

The thermal decomposition furnace 1 is filled up with the object to be treated, and the object to be treated is heated and thermally decomposed while descending in the furnace during continuous operation. The movement of the object to be processed in the furnace is carried out by its own weight drop. Therefore, the rotating mechanism of the furnace body 2 and a feeding mechanism such as a screw are not required, and the structure is simple, and the entire space in the furnace is used for accommodating the object to be treated. Further, the furnace wall is provided with a slight slope (taper) so as to have a V-shape in the left-right direction of FIG. 1B, and the transverse cross section is formed in a divergent shape from the top toward the bottom. This suppresses clogging of the object to be processed,
It becomes easy to move due to its own weight. The residue of the object to be treated discharged from the thermal decomposition furnace 1 is sent to a residue extracting device (not shown) by the carry-out conveyor 10.

When the pyrolysis furnace 1 is started up, the inside of the furnace is replaced with an inert gas such as nitrogen to create an oxygen-blocking atmosphere. The atmosphere in this furnace is checked by an oxygen concentration meter (not shown), and the oxygen concentration is reduced to a predetermined value (for example, 1.0% or less). Then, the charging conveyor 4 is used to fill the thermal decomposition furnace 1 with the material to be processed until it is full. When the filling of the object to be treated is completed, the feeding conveyor 4 is stopped, the heating coil 8 is energized, and the object to be treated in the furnace is heated from top to bottom evenly until it reaches the thermal decomposition temperature, for example, 600 ° C (preheating). To do. Wait for the required time, and if the thermal decomposition of the object to be processed progresses,
Switch to normal operation (continuous operation). That is, the slicing device 7 is activated, the residue of the object to be processed is discharged from the furnace bottom by a fixed amount, and is carried out by the carry-out conveyor 10. The object to be processed in the furnace is
As it is discharged, it falls by its own weight and the level drops. Therefore, the loading conveyor 4 is activated and a new object to be processed is loaded into the thermal decomposition furnace 1. By balancing the input amount of the input conveyor 4 and the output amount of the cutting device 7, the input and output of the object to be processed can be balanced and the processing can be continued.

In the continuous operation, the object to be treated put in the upper part of the pyrolysis furnace 1 is heated and pyrolyzed while descending in the furnace, and the pyrolysis ends when it reaches the bottom of the furnace. Therefore, in the continuous operation, a temperature rising region in which the temperature of the object to be processed is gradually raised from the room temperature to the thermal decomposition temperature is set until the object to be processed is lowered to, for example, approximately half the height of the thermal decomposition furnace 1, and thereafter, The thermal decomposition temperature is set as a thermal decomposition region where thermal decomposition proceeds. To this end, in FIG. 1 (A), the heating coil 8
Is energized separately in the upper half portion 8a and the lower half portion 8b, a relatively large electric power is applied to the upper half portion 8a to raise the temperature of the object to be processed, and a lower electric power is applied to the lower half portion 8b. To maintain the pyrolysis temperature. In the preheating at the start-up described above, the same electric power is applied to the upper half portion 8a and the lower half portion 8b to uniformly heat the entire furnace to the pyrolysis temperature.

[0017]

As described above, according to the present invention, the pyrolysis furnace is constructed in a vertical type so that the object to be treated introduced into the furnace from the top is pyrolyzed while moving to the bottom by its own weight drop. As a result, the object to be treated can be filled in the entire furnace, high thermal efficiency can be obtained, and the mechanism for feeding the object to be treated is not required, and the furnace structure can be simplified. In that case,
By providing the furnace wall with a gradient so that the cross section of the furnace body expands downward, gravity drop becomes easier and the object to be processed moves more smoothly. Moreover, since the pyrolysis furnace is installed vertically, the installation space is small.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, (A) is a vertical sectional view of a pyrolysis furnace, and (B) is a sectional view taken along line BB thereof.

[Explanation of symbols]

1 Pyrolysis furnace 2 furnace body 3 slot 4 Input conveyor 5 Sorting mechanism 6 outlets 7 Cutting device 8 heating coils 9 Exhaust gas piping 10 Carry-out conveyor

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) F27D 11/06 F27D 11/06 Z 4K063 H05B 6/22 H05B 6/22 (72) Inventor Hideaki Tadano Kawasaki City, Kanagawa Prefecture No. 1-1 Tanabe Nitta, Kawasaki-ku Fuji Electric Co., Ltd. (72) Inventor Masanori Matsushita 1-1 No. Tanabe Nitta, Kawasaki-ku, Kawasaki-shi, Kanagawa Fuji Electric Co., Ltd. F-term (reference) 3K059 AB27 AB29 AD03 AD40 CD52 4F301 CA07 CA25 CA46 CA52 CA63 4H012 HB03 HB10 4K045 AA01 BA10 GB05 GD16 4K055 AA00 DA03 4K063 AA01 AA12 BA13 CA01 CA04 CA08 FA36

Claims (8)

[Claims] 1. A thermal decomposition furnace of an organic compound decomposition treatment apparatus for thermally decomposing an organic compound in an oxygen-shielded atmosphere, wherein a furnace body is constituted by a vertical hollow cylinder, and an object to be treated introduced through an upper inlet is provided. A pyrolysis furnace of an organic compound decomposition treatment apparatus, characterized in that it is pyrolyzed while being moved to the discharge port at the bottom by its own weight drop. 2. The thermal decomposition furnace for an organic compound decomposition treatment apparatus according to claim 1, wherein the furnace wall is provided with a gradient so that the cross section of the furnace body expands downward. 3. The thermal decomposition furnace for an organic compound decomposition treatment apparatus according to claim 1, wherein the furnace body is made of a metal or a magnetic material and is induction-heated by a heating coil arranged outside. 4. The thermal decomposition furnace for an organic compound decomposition treatment apparatus according to claim 3, wherein the furnace body has a rectangular cross-sectional shape. 5. The thermal decomposition furnace for an organic compound decomposition treatment apparatus according to claim 3, wherein the magnetic penetration depth of the heating coil is set within the plate thickness of the furnace wall. 6. The thermal decomposition furnace for an organic compound decomposition treatment apparatus according to claim 1, further comprising a cutting device provided at the bottom for discharging the object to be treated in a fixed amount. 7. The thermal decomposition furnace for an organic compound processing apparatus according to claim 6, wherein the cutting device is provided with a pusher for laterally pushing the object to be processed in the furnace at a constant height. 8. The apparatus for treating an organic compound according to claim 7, wherein the pusher is configured as a swing arm that swings about one end as a fulcrum, and the object to be treated is pushed out by the swing motion of the swing arm. Pyrolysis furnace.