JP2001311583A - Rotary kiln - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase a heat transfer area and improve a processing capability without making an entire large-sized rotary kiln of indirect heating system. SOLUTION: An inner cylinder 19 is stored concentrically within a lateral elongated outer cylinder 18 fixed and installed in such a way that an outer heating flow passage 20 is formed between it and the outer cylinder 18, and then the inner cylinder can be rotationally driven. A partition plate 29 having a double-structure is assembled in the inner cylinder 19 in such a way that it may extend in a radial direction from a center part of rotation. An inner space of the partition plate 29 of the double-structure is applied as an inner heating flow passage 30. Waste material 13 supplied into a pyrolysis chamber 19a is heated with hot air 11 flowed in the outer heating flow passage 20 and the inner heating flow passage 30 and further the material is processed with an entire circumferential surface of the pyrolysis chamber 19a being applied as a heat transfer surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an externally heated rotary kiln for pyrolyzing and gasifying waste such as municipal waste.

[0002]

2. Description of the Related Art In recent years, wastes are heated and pyrolyzed in an inert atmosphere, and the generated pyrolysis gas and pyrolysis residues (carbon and ash) are heated to a high temperature with a small amount of air in a combustion / melting furnace. A gasification and melting system has been developed in which ash in refuse is taken out as molten slag by burning it, and demonstration operation is being performed in some parts. In such a method, a rotary kiln is employed to thermally decompose the waste into gas, and the waste is indirectly heated and dried by heat from the outside to be thermally decomposed.

A rotary kiln of the indirect heating type using external heat used for pyrolysis gasification of waste is shown in FIG. Are rotatably supported by the fixedly arranged inlet tube 4 and outlet tube 5 via rotary joints 4a and 5a, and the outer tube 2 is moved about 3 degrees more on the outlet tube 5 side than on the inlet tube 4 side. The inner cylinder 3 is concentrically housed in the outer cylinder 2 so that a heating channel 6 is formed between the outer cylinder 2 and the outer cylinder 2. The inner cylinder 3 constitutes a kiln body 1 having a double cylinder structure, and both ends of the inner cylinder 3 are connected to a supply pipe 7 and a discharge pipe 8 each having a smaller diameter than the inner cylinder 3 so as to be connected to each other. 7 is located in the inlet tube 4 and the discharge tube 8 is located in the outlet tube 5.
Hot air 11 as a heating gas introduced from the hot air supply port 9 of the outlet tube 5 passes through the heating channel 6 and the hot air outlet 1 of the inlet tube 4.
In a state where the kiln body 1 is rotated at a low speed, the waste 13 charged into the charging hopper 12 is passed through the supply pipe 7 of the inlet cylinder 4 by a screw feeder type duster 14 in a state where the kiln body 1 is rotated at a low speed. By supplying hot air 11 from the outlet tube 5 side to the inlet tube 4 side through the heating flow path 6 formed between the inner and outer tubes of the kiln body 1 while gradually supplying the hot air into the tube 3, the inner tube The waste 13 in the inside 3 is heated, dried and thermally decomposed with the periphery of the inner cylinder 3 as a high-temperature heat transfer surface, and the generated pyrolysis gas 13a is passed through the discharge pipe 8 of the outlet cylinder 5 to separate the separation chamber 15. Then, it is taken out from the upper part and sent directly to the downstream combustion / melting furnace, and the pyrolysis residue 13b containing metals is taken out from the lower part after being transferred to the separation chamber 15 through the discharge pipe 8. Combustion after the metal separation process It is to be sent to the melting process. 7
Reference numerals a and 8a denote seal plates.

[0004]

However, since the rotary kiln is an indirect heating system in which only the peripheral surface of the inner cylinder 3 is used as a heat transfer surface, the diameter of the inner cylinder 3 must be reduced in order to increase the processing capacity. It is necessary to increase the length or length, and there is a problem that the whole becomes larger.

On the other hand, there is a method in which a heating tube is arranged in the inner cylinder 3 in order to increase the heat transfer area. However, in this method, waste is entangled with the heating tube, so that stable operation can be performed. There is a problem that it will not be possible.

Accordingly, the present invention is intended to increase the heat transfer area and increase the processing capacity of a rotary kiln of an indirect heating system using external heat without increasing the overall size.

[0007]

According to the present invention, in order to solve the above-mentioned problems, an outer cylinder having a hot air supply port at one longitudinal end and a hot air discharge port at the other end is installed horizontally. In the outer cylinder, the inner cylinder having a waste supply pipe connected to one end in the longitudinal direction and a pyrolysis residue discharge pipe connected to the other end is housed concentrically. Along with forming an outer heating flow path for circulating hot air between the wall surfaces, the supply pipe and the discharge pipe are rotatably penetrated and supported at one end and the other end of the outer cylinder,
The inner cylinder can be driven to rotate, and the inside of the inner cylinder is partitioned over the entire length by a partition plate extending in the radial direction from the center of rotation of the inner cylinder to define a plurality of thermal decomposition chambers in the circumferential direction. The partition plate has a double structure, and a space between the partition plates is formed as an inner heating flow path communicating with the hot air supply port and the hot air discharge port.

When waste is supplied into the inner cylinder through a supply pipe with the inner cylinder rotated at a low speed, the waste is sequentially supplied to each of the pyrolysis chambers of the inner cylinder. If hot air is allowed to flow through the heating flow path around each thermal decomposition chamber of the inner cylinder, the waste will pass through the entire peripheral surface of the thermal decomposition chamber while passing through each thermal decomposition chamber of the inner cylinder. And dried.

When the inner cylinder is supported by the outer cylinder so that the inner cylinder and the outer cylinder can be integrally rotated, the inner cylinder can be rotated stably, and the outer cylinder can be rotated by rotating the inner and outer cylinders. Since the heating channel also rotates, the hot air flowing into the outer heating channel from the hot air supply port can be uniformly dispersed in the circumferential direction, and the thermal decomposition performance can be further stabilized.

[0010] Further, by making the corner portion formed by the connecting portion of the partition plates at the center of rotation of the inner cylinder into an arc surface, the contact between the waste and the heat transfer surface can be performed more smoothly. become able to.

[0011] Further, by forming the partition plate into an uneven shape, the heat transfer area of the thermal decomposition chamber can be further increased.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 5 show an embodiment of the present invention, in which a hot air supply port 16 is provided at one longitudinal peripheral wall and a hot air discharge port 17 is provided at the other longitudinal peripheral wall. The provided horizontally long outer cylinder 18 is fixedly installed so as to be inclined such that the hot air supply port 16 side is lower than the hot air discharge port 17 side by about 3 degrees, and the outer cylinder 18 is provided between the outer cylinder 18 and the inner wall of the outer cylinder. The inner tube 19 is housed concentrically so that an outer heating channel 20 for flowing the hot air 11 is formed, and a supply pipe 21 having a smaller diameter than the inner tube 19 is provided at the center of both ends of the inner tube 19. Discharge pipe 22
And the supply pipe 21 is connected to the hot air outlet 1 of the outer cylinder 18.
7 and the discharge pipe 22 is rotatably penetrated and supported on the end face of the outer cylinder 18 on the side of the hot air supply port 16, respectively.
In addition, supporting rollers 23 each having a fixed position are provided on the outer peripheral surface portions of the supply pipe 21 and the discharge pipe 22 protruding outside the outer cylinder 18.
The tire 24 on the supply pipe 21 side (or the discharge pipe 22 side) is mounted.
Attach the sprocket 25 coaxially to the side surface of No. 4,
A chain 28 is endlessly wound around the sprocket 25 and a sprocket 27 attached to an output shaft of a driving device 26, and the rotational force generated by the driving of the driving device 26 is applied to the chain 28, the sprocket 25, and the tire 24 from the sprocket 27. Then, the inner tube 19 is rotated integrally with the supply pipe 21 and the discharge pipe 22.

Further, in the inner cylinder 19, four (four sets) of partitioning plates 29 having a double structure for maintaining a required interval are provided.
9 are arranged to extend in the radial direction from the rotation center (axial center), each outer end is air-tightly fixed to the inner wall surface of the inner cylinder 19, and each inner end of each partition plate 29 is airtightly integrated. To form four thermal decomposition chambers 19a having the same volume and having a sectoral cross section over the entire length in the longitudinal direction, and radiate between the thermal decomposition chambers 19a by the partition plate 29 having the double structure. Forming an inner heating channel 30 extending in the direction
The end face on the side of the discharge pipe 22 of 0 is a hot air inlet 30a,
The end faces on the supply pipe 21 side are respectively opened as hot air outlets 30 b so as to communicate with the hot air supply port 16 and the hot air discharge port 17.

As shown in detail in FIG. 3, the end of the inner cylinder 19 on the side of the discharge pipe 22 is formed in an arc shape on the outer periphery of the discharge pipe 22 so as to avoid the position of the hot air inlet 30a of the inner heating flow path 30. And a position where the inner heating channel 30 faces the inside of the discharge pipe 22 is closed by a cross-shaped closing plate 32, and only the respective pyrolysis chambers 19 a of the inner cylinder 19 communicate with the inside of the discharge pipe 22. In addition, as shown in detail in FIGS. 4 and 5, the position of the hot air outlet 30 b of the inner heating flow path 30 is provided on the end face of the inner cylinder 19 on the supply pipe 21 side, as shown in detail in FIGS. In addition to attaching the end plate 31 having the same arc shape as the discharge pipe 22 side avoiding the above, the position facing the supply pipe 21 of the partition plate 29 is retracted by a required amount,
At that position, the position where the inner heating flow path 30 faces the inside of the supply pipe 21 is closed with a disk-shaped closing plate 33 and a rectangular piece-shaped closing plate 34, respectively. 19a
Only, and the hot air 11 is allowed to flow through the outer heating channel 20 and the inner heating channel 30 so that the entire peripheral surface of each of the thermal decomposition chambers 19a serves as a heat transfer surface.

Further, a screw feeder-type duster 14 having a hopper 12 for charging waste 13 is inserted from the outer end face of the supply pipe 21 at the center of rotation of the supply pipe 21 and installed. Each pyrolysis chamber 19a through the supply pipe 21
And a pyrolysis gas 13a, which is pyrolyzed in each of the pyrolysis chambers 19a and discharged through the discharge pipes 22, and a pyrolysis residue at the outer end of the discharge pipe 22. Separation chamber 1 in which 13b is separated and taken out
5 is provided.

The closing plate 3 provided at the end of the inner cylinder 19
2 is for preventing the hot air 11 in the inner heating channel 30 from leaking into the discharge pipe 22.
This is to form a space for discharging the pyrolysis residue 13b in the pyrolysis chamber 19a into the discharge pipe 22. In addition, blocking plate 3
3 and 34, the hot air 11 in the inner heating channel 30 is supplied by the supply pipe 2.
The blocking plate 33 is formed in a disk shape so that the waste 13 supplied into the pyrolysis chamber 19a does not flow backward due to the rotation of the inner cylinder 19. It is to function as.

The drive unit 26 drives the inner cylinder 19 to supply the supply pipe 2
In a state where the waste 13 is rotated at a low speed integrally with the inner pipe 1 and the discharge pipe 22, the waste 13 is supplied to each of the pyrolysis chambers 19 a of the inner pipe 19 through the supply pipe 21 by the duster 14.
When the hot air 11 is caused to flow through the inner heating flow path 30 formed between the outer heating flow path 20 formed on the outer periphery of the inner tube 19 and each of the pyrolysis chambers 19a in the inner cylinder 19, the waste 13 While being passed through the chamber 19a, it is heated and dried by external heat, is thermally decomposed and gasified, passes through the discharge pipe 22, is separated into the pyrolysis gas 13a and the pyrolysis residue 13b in the separation chamber 15, and is taken out.

In the above description, the four pyrolysis chambers 19a having a fan-shaped cross section are heated from the outer peripheral surface by the hot air 11 flowing through the outer heating channel 20 and the hot air 11 flowing through the inner heating channel 30, respectively. Therefore, the heat transfer surface can be provided on the entire circumference, so that the heat transfer efficiency can be improved. In this case, for example, when the volume ratio of the waste 13 to be treated is the same as that of the inner cylinder having the same inner diameter as shown in FIG. 12, the heat transfer area is (π + 4) / π ≒ 2. 27 times. Accordingly, the processing capacity can be increased without increasing the size of the entire kiln. Further, the thermal decomposition chamber 19a
Is hollow and there is nothing that waste 13 is entangled with,
This is also advantageous compared to a method in which a heating tube is arranged in the inner cylinder.

FIGS. 6 and 7 show another embodiment of the present invention. As shown in FIG. 12, one end of the horizontally long outer cylinder 2 in the longitudinal direction is connected to the hot air discharge port 10. The other end of the outer cylinder 2 is rotatably supported via the rotary joints 4a and 5a. Cylinder 4
Tires 24 are attached to the outer peripheral surface portions of the outer cylinder 2 and the outlet cylinder 5, respectively, and the respective tires 24 are received by the support rollers 23 whose positions are fixed. Attach the large-diameter gear 36 at the position
A drive gear 38 rotated by a motor 37 meshes with the large-diameter gear 36 so that the outer cylinder 2 is received by the support roller 23 and rotated by the drive of the motor 37. An inner cylinder 19 having the same configuration as that shown in FIGS. An outer heating flow path 20 through which hot air 11 flows is formed, and the inner cylinder 19 and the outer cylinder 2 are attached to a fixing member 35 disposed at appropriate positions in the circumferential direction at both ends in the longitudinal direction of the inner cylinder 19. So that the inner cylinder 19 can rotate integrally with the outer cylinder 2. Further, a supply pipe 21 and a discharge pipe 22 having a smaller diameter than the inner cylinder 19 are provided at the center of both ends of the inner cylinder 19. The supply pipe 21 is located in the inlet pipe 4 and the discharge pipe 22 is located in the outlet pipe 5.
0 and the inner heating flow path 30 communicate with the hot air supply port 9 and the hot air discharge port 10. In addition, 21
Reference numerals a and 22a denote seal plates, and other structures are the same as those shown in FIGS. 1 to 5, and the same parts are denoted by the same reference numerals.

According to this embodiment, when the outer cylinder 2 is rotated by the driving of the motor 37, the inner cylinder 19 is integrally rotated via the fixing member 35, so that the outer heating channel 20 is also rotated. Therefore, the hot air 11 flowing from the hot air supply port 9 into the outer heating channel 20 can be uniformly dispersed in the circumferential direction, and the thermal decomposition performance of the waste 13 can be further stabilized.

FIG. 8 shows still another embodiment of the present invention. In the same configuration as that shown in FIGS. 1 to 5 or FIGS. The corners, which are connecting portions between the inner ends of the partition plate 29 having a double structure, which are formed so as to be divided into four pyrolysis chambers 19a in the directions, are formed as arc surfaces 29a without forming a 90-degree angle. The inside corner portion of each thermal decomposition chamber 19a is formed in a cylindrical shape as a whole.

When configured as shown in FIG.
By the action of a, the contact between the waste 13 and the heat transfer surface in the inner corner portion of each of the pyrolysis chambers 19a can be performed more smoothly, so that the waste 13 is more uniformly heated and dried. Can be.

FIG. 9 shows still another embodiment of the present invention. In a configuration similar to that shown in FIG. 1 to FIG. 5 or FIG. 6 and FIG. In the same direction. In addition,
Like the one shown in FIG. 8, the inner corner portion of each pyrolysis chamber 19a may be an arc surface 29a.

When configured as shown in FIG.
Is curved, the area of the inner heating channel 30 can be increased as compared with those shown in FIG. 1 to FIG. 5 or FIG. 6 and FIG. Become.

FIG. 10 shows still another embodiment of the present invention. In a configuration similar to that shown in FIG. 1 to FIG. 5 or FIG. 6 and FIG. It is processed so as to have irregularities on both sides. Also in this case, as in the case shown in FIG. 8, it is optional to make the inner corner portion of each of the thermal decomposition chambers 19a an arc surface 29a.

When the structure shown in FIG. 10 is used, the partition plate 29 can be provided more than the structure shown in FIGS. 1 to 5 or FIGS.
, The heat transfer area of each thermal decomposition chamber 19a can be increased.

It is to be noted that the partition plate 29 processed into a waveform as shown in FIG. 10 may be adopted in the embodiment shown in FIG.
Further, in each of the above embodiments, the case where four pyrolysis chambers 19a are formed in the circumferential direction is shown.
For example, a multi-chamber structure of five, six, seven, etc. may be used. In the embodiment, the hot air inlet 30 a and the hot air outlet 30 b of the inner heating channel 30 are opened at the end surface of the inner cylinder 19. However, as shown in FIG. 11, the end face of the inner cylinder 19 is closed with a ring-shaped end plate 31a, and the inner cylinder 1 is closed.
A hot air inlet 30a and a hot air outlet 30b may be opened in the peripheral surface of the end portion of the inner cylinder 9. Further, the inner cylinder 1 shown in FIG.
9 may be employed as the drive mechanism of FIG. 6 or the chain / sprocket type of FIG. 1 may be employed as the drive mechanism of the outer cylinder 2 shown in FIG. It is needless to say that the use of the heat treatment other than 13 is optional, and that various changes can be made without departing from the scope of the present invention.

[0029]

As described above, according to the rotary kiln of the present invention, the outer cylinder having the hot air supply port at one longitudinal end and the hot air discharge port at the other end is installed horizontally. The inner cylinder connected to a waste supply pipe at one longitudinal end and a pyrolysis residue discharge pipe connected to the other end is concentrically housed, and the outer wall of the inner cylinder and the inner wall of the outer cylinder are connected. Along with forming an outer heating flow path through which hot air flows, the supply pipe and the discharge pipe are rotatably penetrated and supported at one end and the other end of the outer cylinder,
The inner cylinder can be driven to rotate, and the inside of the inner cylinder is partitioned over the entire length by a partition plate extending in the radial direction from the center of rotation of the inner cylinder to define a plurality of thermal decomposition chambers in the circumferential direction. Since the partition plate has a double structure and an inner heating flow passage communicating between the partition plate and the hot air supply port and the hot air discharge port, the entire peripheral surface of the thermal decomposition chamber is used as a heat transfer surface to heat waste,
Since drying can be performed and the heat transfer area can be increased, it is possible to increase the processing capacity without increasing the size of the kiln as a whole. By configuring so that the cylinder can rotate integrally, the inner cylinder can be rotated stably and the outer heating channel can be rotated, so that hot air flowing from the hot air supply port into the outer heating channel can be heated. Can be uniformly dispersed in the circumferential direction, the thermal decomposition performance of waste can be more stabilized, and the corner part by the connecting part of the partition plates at the center of rotation of the inner cylinder has an arcuate surface. With this configuration, the contact between the waste and the heat transfer surface can be improved, the waste can be more uniformly heated and dried, and the partition The board is processed into irregularities. It makes advantageous to be able to further increase the heat transfer area and an excellent effect and the like.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of a rotary kiln of the present invention.

FIG. 2 is an enlarged view in the direction of arrows AA in FIG. 1;

FIG. 3 is an enlarged view in the direction of arrows BB in FIG. 1;

FIG. 4 is an enlarged perspective view taken along the line CC in FIG. 1;

5 is a view in the direction of arrows DD in FIG. 4;

FIG. 6 is a schematic diagram showing another embodiment of the present invention.

FIG. 7 is a view as seen in the direction of arrows EE in FIG. 6;

FIG. 8 is a schematic sectional view of an inner cylinder showing still another embodiment of the present invention.

FIG. 9 is a schematic sectional view of an inner cylinder showing still another embodiment of the present invention.

FIG. 10 is a schematic sectional view of an inner cylinder showing still another embodiment of the present invention.

FIG. 11 is an external view of an inner cylinder showing still another embodiment of the present invention.

FIG. 12 is a schematic view showing an example of a conventional rotary kiln.

[Explanation of symbols]

 2 Outer tube 4 Inlet tube 5 Outlet tube 9 Hot air supply port 10 Hot air discharge port 11 Hot air 13 Waste 16 Hot air supply port 17 Hot air discharge port 18 Outer cylinder 19 Inner cylinder 19a Thermal decomposition chamber 20 Outer heating flow path 21 Supply pipe 22 Discharge Pipe 26 Drive device 29 Partition plate 29a Arc surface 30 Inside heating channel

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) F27B 7/36 B09B 3/00 ZAB (72) Inventor Yoshimaru Suzuki 2-1-1 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries, Ltd. Tokyo 1st Factory F-term (reference) 4D004 AA46 AC04 CA24 CB09 CB31 4K061 AA08 BA12 CA02 CA08 CA27

Claims (4)

[Claims] 1. An outer cylinder provided with a hot air supply port at one longitudinal end and a hot air discharge port at the other end is installed horizontally, and a waste supply pipe is connected to one longitudinal end of the outer cylinder. The other end is connected to the inner tube connected to the discharge pipe of the pyrolysis residue, and the outer tube is concentrically housed to form an outer heating channel through which hot air flows between the outer wall surface of the inner tube and the inner wall surface of the outer tube. Together, the supply pipe and the discharge pipe are rotatably penetrated and supported at one end and the other end of the outer cylinder,
The inner cylinder can be driven to rotate, and the inside of the inner cylinder is partitioned over the entire length by a partition plate extending in the radial direction from the center of rotation of the inner cylinder to define a plurality of thermal decomposition chambers in the circumferential direction. A rotary kiln having a structure in which a partition plate has a double structure and an inner heating flow path communicating between the partition plate and the hot air supply port and the hot air discharge port is provided. 2. An outer cylinder having one end in the longitudinal direction rotatably supported on an inlet cylinder having a hot air discharge port and the other end rotatably supported on an outlet cylinder having a hot air supply port, respectively. The inner cylinder is concentrically arranged in the cylinder to form an outer heating flow path for flowing hot air between the inner wall surface of the outer cylinder and the outer wall surface of the inner cylinder, and the inner cylinder is integrated with the outer cylinder. The outer cylinder is supported so as to be rotatable, and both ends of the inner cylinder are connected to the small-diameter supply pipe and the discharge pipe arranged in the inlet cylinder and the outlet cylinder, respectively. A plurality of thermal decomposition chambers are defined in the circumferential direction by partitioning the entire length with a partition plate extending radially from the rotation center of the inner cylinder, and the hot air supply port is formed between the partition plates by forming the partition plate into a double structure. A rotary kiln having an internal heating flow passage communicating with a hot air outlet . 3. The rotary kiln according to claim 1, wherein a corner portion formed by a connecting portion between the partition plates at a rotation center portion of the inner cylinder has an arc surface. 4. The rotary kiln according to claim 1, wherein the partition plate is processed into irregularities.