JP3369456B2 - Carbonization device and carbonization method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carbonization apparatus and a carbonization method capable of carbonizing combustible waste.

[0002]

2. Description of the Related Art As a conventional carbonization treatment apparatus, for example, Japanese Patent Laid-Open Nos. 8-245966 and 6-145668.
Japanese Patent Publication, Japanese Patent Publication No. 5-81634, Japanese Patent Laid-Open No. 59-1
There are those disclosed in Japanese Patent No. 45282 and Japanese Patent Laid-Open No. 57-96084. That is, the waste is heated to carbonize it, the combustible gas generated by the carbonization is burned in the combustion chamber, and the heat is used to heat the waste.

[0003]

However, since the combustible gas generated by carbonization does not always occur uniformly from the start of generation to the end of generation, the conventional carbonization apparatus and the carbonization treatment method treat the generated combustible gas. There is a problem that it is difficult to control combustion for completely burning and heating for sufficiently carbonizing wastes while saving fuel, and it is difficult to perform efficient carbonization.

The present invention has been made by paying attention to such a conventional problem, and it is possible to easily control the combustion of the combustible gas and the heating by the fuel according to the generation of the combustible gas due to carbonization. It is an object of the present invention to provide a carbonization apparatus and a carbonization method capable of realizing efficient carbonization.

[0005]

To achieve the above object, a carbonizing apparatus according to the present invention comprises a heating chamber, a carbonizing chamber, a reburning chamber, a heating chamber burner, a reburning chamber burner, a reburning blower, and a heating blower. The heating chamber is provided around the carbonization chamber so that the carbonization chamber can be heated; the carbonization chamber is a primary gas flow communicating with the inlet of the object to be treated and the reburn chamber. The reburn chamber has a secondary gas flow path communicating with the heating chamber; the heating chamber burner is provided to burn the combustible gas inside the heating chamber; The reburning blower is provided to be capable of burning the combustible gas inside the reburning chamber; the reburning blower is provided to introduce the gas generated in the carbonizing chamber into the reburning chamber through the primary gas flow path; Pass the gas inside the reburn chamber through the secondary gas flow path. Is provided so as to be introduced into the heating chamber; the sensor is provided so as to detect the temperature in the vicinity of the primary gas flow path; the control device is provided with the heating chamber burner and the The combustion power of the reburn chamber burner and the operations of the reburn blower and the heating blower are controlled.

In the carbonization apparatus according to the present invention, the material to be treated is charged into the carbonization chamber through the charging port to burn the heating chamber burner,
The carbonization chamber is heated from the surroundings. The object to be treated is heated in the carbonization chamber to generate combustible gas. The generated combustible gas is
It is sent to the reburn chamber through the primary gas flow path by the reburn blower. In the reburn chamber, a part of the combustible gas is burned by the reburn chamber burner. The remaining combustible gas and the heated gas in the reburn chamber are sent to the heating chamber by the heating blower through the secondary gas flow path. In the heating chamber, the remainder of the combustible gas is burned by the heating chamber burner and heats the carbonization chamber together with the heated gas from the reburning chamber. The sensor detects the temperature in the vicinity of the primary gas flow path, and the control device controls the combustion power of the heating chamber burner and the reburning chamber burner and the operation of the reburning blower and the heating blower according to the temperature detected by the sensor. Since the generation of combustible gas due to carbonization is affected by the heating temperature, it is possible to easily control the combustion of the combustible gas and the heating by the fuel, and to efficiently perform the carbonization process.

A carbonization apparatus according to a second aspect of the present invention is the carbonization apparatus according to the first aspect, wherein the heating chamber burner introduces a first burner, a second burner, and external air into the heating chamber. The burner comprises a first burner fan for assisting combustion of the burner and a second burner fan for assisting combustion of the second burner by introducing external air into the heating chamber, and the reburn chamber burner includes a third burner and external air. Is introduced into the reburn chamber to assist combustion of the third burner, and the first burner, the second burner, and the third burner fan are provided.
Each of the burner, the first burner fan, the second burner fan and the third burner fan can operate in at least two levels of strength and weakness; the controller controls the first burner, the third burner fan according to the temperature detected by the sensor. Controlling the combustion power of the second burner and the third burner, the operation of the first burner fan, the operation of the second burner fan and the third burner fan, the operation of the reburning blower, and the operation of the heating blower. , Characterized.

In the carbonizing apparatus according to the second aspect of the present invention, the heating chamber burner has a first burner, a first burner fan, a second burner and a second burner fan, and the reburn chamber burner has a third burner.
The burner and the third burner fan are provided, and each of them can operate in at least two stages of strength and weakness, so that the combustion power of the heating chamber burner and the reburn chamber burner can be adjusted in stages.

A carbonization apparatus according to a third aspect of the present invention is the carbonization apparatus according to the second aspect, wherein the controller controls the first burner, the second burner, and the third burner at the start of carbonization of the workpiece. The combustion power of the burner is increased, the operation of the first burner fan, the second burner fan and the third burner fan is increased, and the reburning blower and the heating blower are stopped; ~ 140
When a temperature of ° C is detected, the combustion power of the first burner and the second burner is weakened, the operation of the first burner fan and the second burner fan is weakened, and the reburning blower and the heating blower are weakened. When the sensor detects a temperature of 170 to 190 ° C. during carbonization, the second burner is stopped, the combustion power of the third burner is weakened, and the operation of the third burner fan is weakened; When the sensor detects a temperature of 300 to 330 ° C. during carbonization, the combustion power of the second burner is weakened; when the carbonization of the workpiece is completed, the first burner and the second burner are stopped,
Increasing the combustion power of the third burner, and increasing the operation of the first burner fan, the second burner fan and the third burner fan; a predetermined time after stopping the first burner and the second burner Then stop the third burner;
After a lapse of a predetermined time after stopping the third burner, the first burner fan, the second burner fan and the third burner fan are stopped, and the reburning blower and the heating blower are stopped. And

In the carbonization apparatus according to the third aspect of the present invention, when the sensor detects a temperature of 130 to 140 ° C. and when the sensor detects a temperature of 170 to 190 ° C. from the start of carbonization of the object to be treated, When the sensor detects a temperature of 300 to 330 ° C., when the carbonization of the object to be processed is completed, after a predetermined time from stopping the first burner and the second burner, and when the third
The combustion power of the heating chamber burner and the reburning chamber burner and the operation of the reburning blower and the heating blower are controlled separately for a predetermined time after the burner is stopped. Thereby, an efficient carbonization process can be specifically realized.

The carbonization method according to the present invention of claim 4 is
The heating chamber burner is burned in a heating chamber provided around the carbonization chamber to heat the carbonization chamber, the gas generated in the carbonization chamber is introduced into the reburn chamber by a reburn blower, and the reburn chamber burner is used to reburn the gas. Burn some of the combustible gas inside the chamber,
A carbonization method in which the remaining combustible gas and the heated gas inside the reburn chamber are introduced into the heating chamber by a blower for heating; the combustion power of the heating chamber burner is arranged in descending order of temperature. Adjustable up to 3 heating levels, the combustion power of the reburn chamber burner can be adjusted to two levels, high and low; the temperature of the gas introduced from the carbonization chamber to the reburn chamber is detected by a sensor; At the start of carbonization, the combustion power of the heating chamber burner is set to the first level, the combustion power of the reburning chamber burner is set to a high level, and the reburning blower and the heating blower are stopped; ~
When the temperature of 140 ° C. is detected, the combustion power of the heating chamber burner is set to the second level, and the reburning blower and the heating blower are operated;
When the temperature of 0 to 190 ° C. is detected, the combustion power of the heating chamber burner is set to the third level, and the combustion power of the reburning chamber burner is set to a low level;
When the temperature of 30 ° C. is detected, the combustion power of the heating chamber burner is set to the second level; when the carbonization of the workpiece is completed,
The heating chamber burner is stopped, and the combustion power of the reburning chamber burner is set to a high level; a predetermined time after the heating chamber burner is stopped, the reburning chamber burner is stopped; the reburning chamber burner is stopped. After a predetermined time, the reburning blower and the heating blower are stopped.

In the carbonization method according to the present invention, the combustion power of the heating chamber burner and the reburning chamber burner and the operation of the reburning blower and the heating blower are staged according to the temperature detected by the sensor from the start of carbonization of the object to be treated. Can be controlled in a specific manner, and an efficient carbonization treatment can be specifically realized.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of the present invention. As shown in FIG. 1, the carbonization device includes a main body 1
Inside, there are provided a heating chamber 2, a carbonization chamber 3, a reburn chamber 4, a heating chamber burner 5, a reburn chamber burner 6, a reburn blower 7, a heating blower 8, a sensor 9 and a control device 10. The side surface of the main body 1 has a gap between the heating chamber 2, the carbonization chamber 3, and the reburn chamber 4.

The heating chamber 2 surrounds the carbonization chamber 3 so as to be able to heat the carbonization chamber 3 and is provided around the carbonization chamber 3. The carbonization chamber 3 is
It has a primary gas flow path 3b and a charcoal outlet 3c which communicate with the input port 3a of the object to be treated and the reburn chamber 4. An automatic locking device (not shown) is provided at the charging port 3a and the charcoal discharging port 3c. The automatic locking device automatically locks the charging port 3a and the charcoal discharging port 3c by the start of carbonization of the object to be processed, and automatically locks when all the operations are stopped after a predetermined time has passed after the carbonization process. To release. A stirring device 3d is provided inside the carbonization chamber 3. Stirrer 3d
Is rotated by a motor to stir the object to be treated inside the carbonization chamber 3. The reburn chamber 4 is provided above the heating chamber 2. The reburn chamber 4 has a secondary gas flow path 4a communicating with the heating chamber 2.
have.

The heating chamber burner 5 includes a first burner 5a and a second burner 5a.
It comprises a burner 5b, a first burner fan 5c and a second burner fan 5d. The first burner fan 5c introduces external air into the heating chamber 2 to assist the combustion of the first burner 5a. The second burner fan 5d introduces external air into the heating chamber 2 to assist the combustion of the second burner 5b. Each of the first burner 5a, the second burner 5b, the first burner fan 5c, and the second burner fan 5d can operate in two levels of strength. As a result, the heating chamber burner 5 can adjust the combustion power to the first to third heating levels in the descending order of temperature.
First burner 5a, second burner 5b, first burner fan 5
The c and the second burner fan 5d are provided so as to burn the combustible gas (carbonized gas) inside the heating chamber 2. The carbonization chamber 3 has an indirect heating structure that does not directly receive the flame of the heating chamber burner 5.

The reburn chamber burner 6 comprises a third burner 6a and a third burner fan 6b. 3rd burner fan 6b
Introduces outside air into the reburn chamber 4 to assist the combustion of the third burner 6a. The third burner 6a and the third burner fan 6b can each operate in two levels of strength. As a result, the reburn chamber burner 6 can adjust the combustion power to two levels, high and low. The third burner 6 a and the third burner fan 6 b are provided so as to burn the combustible gas inside the reburn chamber 4.

The reburning blower 7 is provided so as to introduce the gas generated in the carbonization chamber 3 into the reburning chamber 4 through the primary gas passage 3b. The heating blower 8 is provided so as to introduce the gas inside the reburn chamber 4 into the heating chamber 2 through the secondary gas passage 4a.

The sensor 9 is provided so as to detect the temperature in the vicinity of the primary gas passage 3b. The sensor 9 is connected to the control device 10. The control device 10 controls the first burner 5a and the second burner 5b according to the temperature detected by the sensor 9.
And the combustion power of the third burner 6a, the first burner fan 5
c, the second burner fan 5d and the third burner fan 6b
Operation, reburning blower 7 operation and heating blower 8
The operation of is automatically controlled.

That is, the control device 10 increases the combustion power of the first burner 5a, the second burner 5b, and the third burner 6a at the start of carbonization of the object to be treated, and the first burner fan 5
c, the second burner fan 5d and the third burner fan 6b
The combustion power of the heating chamber burner 5 is set to the maximum
The level is set, and the reburning blower 7 and the heating blower 8 are stopped. At this stage, all the water is evaporated from the object to be treated. In the heating chamber 2, the odor generated from the object to be treated is decomposed and the combustible gas is completely incinerated.

When the sensor 9 is carbonized, the control device 10
When the temperature of 0 to 140 ° C. is detected, the combustion power of the first burner 5a and the second burner 5b is weakened, the operation of the first burner fan 5c and the second burner fan 5d is weakened, and the combustion of the heating chamber burner 5 is performed. The power is brought to the second level, and the reburning blower 7 and the heating blower 8 are operated. Heating chamber burner 5
The reason why the combustion power of 1 is lowered from the first level to the second level is that when the heating temperature rises rapidly, the thermal decomposition of the object to be treated progresses rapidly and a large amount of combustible gas is generated. At this stage, the thermal decomposition of the object to be treated gradually progresses, the generation of combustible gas also gradually increases, and the temperature inside the heating chamber 2 gradually rises.

When the sensor 9 is carbonized, the control device 10 is set to 17
When the temperature of 0 to 190 ° C. is detected, the second burner 5b is stopped, the combustion force of the third burner 6a is weakened, the operation of the third burner fan 6b is weakened, and the combustion force of the heating chamber burner 5 is changed to the first. Set to 3 levels. The reason why the combustion power of the heating chamber burner 5 is lowered from the second level to the third level is that most of the objects to be treated undergo thermal decomposition at this temperature and a large amount of combustible gas is generated.

When the sensor 9 is carbonized, the control device 10 controls
When the temperature of 0 to 330 ° C. is detected, the combustion power of the second burner 5b is weakened to bring the combustion power of the heating chamber burner 5 to the second level. The combustion power of the heating chamber burner 5 is changed from the third level to the second level.
The reason why the temperature is raised to the level is to keep the rate of temperature rise inside the heating chamber 2 constant and to completely thermally decompose all the objects to be treated.

The controller 10 stops the first burner 5a and the second burner 5b when the carbonization of the object to be treated is completed, and makes the combustion power of the third burner 6a strong, and the first burner fan 5
c, the second burner fan 5d and the third burner fan 6b
Strengthen the operation of. At this stage, the combustible gas remaining inside the carbonization chamber 3 is burned after the object to be treated is completely pyrolyzed.

The controller 10 stops the first burner 5a and the second burner 5b and, after a predetermined time, stops the operation of the third burner 6a.
Stop a. The control device 10 stops the first burner fan 5c, the second burner fan 5d, and the third burner fan 6b, and stops the reburning blower 7 and the heating blower 8 after a predetermined time has elapsed since the third burner 6a was stopped. Then, the operation ends. For a predetermined time after stopping the third burner 6a,
The operation of the first burner fan 5c, the second burner fan 5d and the third burner fan 6b remains strong, the reburning blower 7 and the heating blower 8 are operating, and the heating chamber 2 and the carbonization chamber 3 rapidly To be cooled. At the end of the operation, the temperature of the sensor 9 is set to about 80 ° C.

Next, the operation will be described. In the carbonization apparatus, the object to be treated is charged into the carbonization chamber 3 through the charging port 3a, the heating chamber burner 5 is burned, and the carbonization chamber 3 is heated from the surroundings. The object to be treated is, for example, food waste from home or combustible industrial waste, but is not limited to waste and may be wood for charcoal production, for example. The heating chamber burner 5 has a first burner 5a, a first burner fan 5c, a second burner 5b and a second burner fan 5d, each of which can operate in two strong and weak stages. The first to third heating levels can be adjusted in stages. The charging port 3a and the charcoal outlet 3c are automatically locked by an automatic locking device (not shown) when carbonization of the object to be treated is started. Therefore, the charging port 3a and the charcoal discharging port 3c
It is possible to prevent accidental opening due to accidental opening.

The object to be treated is heated in the carbonization chamber 3 to generate combustible gas. The temperature of thermal decomposition of the object to be treated differs depending on its type, and combustible gas due to carbonization is gradually generated from those which are easily thermally decomposed. Some of the objects to be processed are about 70
Thermal decomposition begins at around ℃. The generated combustible gas is sent to the reburn chamber 4 through the primary gas flow path 3b by the reburn blower 7. In the reburn chamber 4, the reburn chamber burner 6 burns a part of the surplus combustible gas in the heating chamber 2 at a high temperature.
The reburn chamber burner 6 has a third burner 6a and a third burner fan 6b, which can be operated in two stages of strength and weakness respectively, so that the combustion power of the reburn chamber burner 6 can be adjusted in two levels, high and low. is there.

The remaining combustible gas and the heated gas in the reburning chamber 4 are sent to the heating chamber 2 by the heating blower 8 through the secondary gas passage 4a. In the heating chamber 2, the remaining burnable gas is burned by the heating chamber burner 5, and the carbonization chamber 3 is heated together with the heated gas from the reburning chamber 4. The temperature inside the heating chamber 2 gradually rises due to the combustion of the fuel and the generated combustible gas by the heating chamber burner 5. Heating chamber 2
As the temperature inside the container rises, the thermal decomposition of the object to be processed gradually progresses, the combustible gas continues to be generated, and the thermal decomposition of the object to be processed ends, whereby the generation of the combustible gas is completed. in this way,
Since the combustible gas generated from the object to be processed is used for heating the object to be processed, the fuel required for heating can be significantly reduced.

The sensor 9 detects the temperature in the vicinity of the primary gas flow path 3b, and the control unit 10 controls the combustion power of the heating chamber burner 5 and the reburning chamber burner 6 and the reburning blower 7 according to the temperature detected by the sensor 9. And the operation of the heating blower 8 is controlled stepwise. That is, the control device 10 detects when the sensor 9 detects a temperature of 130 to 140 ° C. from the start of carbonization of the object to be processed, when the sensor 9 detects a temperature of 170 to 190 ° C., and when the sensor 9 detects 300 to 330. When the temperature of ° C is detected, when the carbonization of the object to be treated is completed, a predetermined time after stopping the first burner 5a and the second burner 5b, and a predetermined time after stopping the third burner 6a. The combustion power of the heating chamber burner 5 and the reburning chamber burner 6 and the operation of the reburning blower 7 and the heating blower 8 are controlled separately. Table 1 shows the control contents of the control device 10.

[0029]

[Table 1]

Since the generation of combustible gas due to carbonization is affected by the heating temperature, it is possible to easily control the combustion of the combustible gas and the heating by the fuel, and to carry out an efficient carbonization treatment specifically. Can be realized.

The automatic lock device automatically releases the lock when a predetermined time has elapsed after the carbonization process and all operations have been stopped. After releasing the automatic locking device, the charcoal outlet 3c
Take the charcoal from. The resulting charcoal can be used for fuel, water purification, and various other purposes. The carbonization equipment can make the equipment compact, and is suitable as a waste treatment machine not only in urban areas but also in small-scale business establishments.

[0032]

According to the carbonizing apparatus and the carbonizing method of the present invention, the combustion power of the heating chamber burner and the reburning chamber burner and the operation of the reburning blower and the heating blower are controlled according to the temperature detected by the sensor. Therefore, according to the generation of the combustible gas due to the carbonization, the control of the combustion of the combustible gas and the control of the heating by the fuel can be easily performed, and the efficient carbonization process can be realized.

In particular, according to the carbonizing apparatus of the present invention of claim 2, the combustion power of the heating chamber burner and the reburning chamber burner can be adjusted stepwise.

Particularly, according to the carbonization apparatus of the present invention of claim 3, the combustion power of the heating chamber burner and the reburn chamber burner and the reburn blower according to the temperature detected by the sensor from the start of carbonization of the object to be treated. Also, the operation of the heating blower can be controlled stepwise to specifically realize the efficient carbonization treatment.

[Brief description of drawings]

FIG. 1 is a front view (A), a right side view (B), a left side view (C) and a plan view (D) of a carbonization apparatus according to an embodiment of the present invention.

[Explanation of symbols]

1 body 2 heating chambers 3 carbonization chamber 4 Reburn room 5 heating chamber burner 6 Reburning room burner 7 Reburner blower 8 Blower for heating 9 sensors 10 Control device

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI F23G 5/027 ZAB F23G 5/16 ZABB 5/16 ZAB B09B 3/00 ZAB (56) Reference JP-A-3-239793 (JP) , A) JP-A-3-240925 (JP, A) JP-A-50-90605 (JP, A) JP-A-48-69129 (JP, A) JP-A-8-104880 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) C10B 53/00 B09B 3/00 302 B09B 3/00 C10B 41/00 F23G 5/027 F23G 5/16

Claims (4)

(57) [Claims] 1. A heating chamber, a carbonizing chamber, a reburning chamber, a heating chamber burner, a reburning chamber burner, a reburning blower, a heating blower, a sensor, and a controller, and the heating chamber is capable of heating the carbonizing chamber. The carbonization chamber is provided around the carbonization chamber, and the carbonization chamber has an inlet for the object to be treated and a primary gas flow path communicating with the reburn chamber, and the reburn chamber is a secondary gas flow communicating with the heating chamber. A passage, the heating chamber burner is provided to burn the combustible gas inside the heating chamber, the reburn chamber burner is provided to burn the flammable gas inside the reburn chamber, the reburn blower The gas generated in the carbonization chamber is added to the 1
The heating blower is installed so as to be introduced into the reburn chamber through a secondary gas flow path, and the heating blower is installed so as to introduce gas inside the reburn chamber into the heating chamber through the secondary gas flow path. The control device is provided to detect the temperature in the vicinity of the next gas flow path, and the control device is configured to detect the combustion power of the heating chamber burner and the reburning chamber burner according to the temperature detected by the sensor, and the reburning blower and the heating blower. A carbonization device characterized by controlling the operation of the carbonization device. 2. The heating chamber burner includes a first burner, a second burner, a first burner fan for introducing external air into the heating chamber to assist combustion of the first burner, and external air for the heating chamber. A second burner fan that is introduced into the reburn chamber to assist the combustion of the second burner. The reburn chamber burner introduces a third burner and external air into the reburn chamber to introduce the third burner.
It comprises a third burner fan for assisting combustion of the burner, and the first burner, the second burner, the third burner, the first burner fan, the second burner fan and the third burner fan are each at least strong and weak. The control device is operable in stages, and the control device is responsive to the temperature detected by the sensor, the combustion power of the first burner, the second burner, and the third burner, the first burner fan, the second burner fan, and The carbonization device according to claim 1, wherein the operation of the third burner fan, the operation of the reburning blower, and the operation of the heating blower are controlled. 3. The control device increases the combustion power of the first burner, the second burner and the third burner at the start of carbonization of the object to be treated, and the first burner fan and the second burner are strengthened. When the operation of the fan and the third burner fan is strengthened, the reburning blower and the heating blower are stopped, and the sensor detects a temperature of 130 to 140 ° C. during carbonization, the first burner and the second burner The combustion power of the burner is weakened, the operation of the first burner fan and the second burner fan is weakened, the reburning blower and the heating blower are operated, and the sensor operates at a temperature of 170 to 190 ° C. during carbonization. When it is detected, the second burner is stopped, the combustion force of the third burner is weakened, the operation of the third burner fan is weakened, and the sensor detects the temperature of 300 to 330 ° C. during carbonization. Degree is detected, the combustion force of the second burner is weakened, and when the carbonization of the object to be treated is completed, the first burner and the second burner are stopped, and the combustion force of the third burner is increased, Intensifying the operation of the first burner fan, the second burner fan, and the third burner fan, stopping the third burner after a predetermined time from stopping the first burner and the second burner, and After a lapse of a predetermined time after stopping the third burner, the first burner fan, the second burner fan, and the third burner fan are stopped, and the reburning blower and the heating blower are stopped. The carbonization device according to claim 2. 4. A heating chamber burner is burned in a heating chamber provided around the carbonization chamber to heat the carbonization chamber, and gas generated in the carbonization chamber is introduced into the reburning chamber by a reburning blower.
By a part of the combustible gas inside the reburn chamber is burned by the reburn chamber burner, the remaining gas of the flammable gas inside the reburn chamber and the heated gas are introduced into the heating chamber by a blower for heating. Then, the combustion power of the heating chamber burner is set to the first to the third in descending order of temperature.
It can be adjusted to a heating level, the combustion power of the reburning chamber burner can be adjusted to two levels, high and low, and the temperature of the gas introduced from the carbonizing chamber to the reburning chamber is detected by a sensor to carbonize the object to be treated. At the start, the combustion force of the heating chamber burner is set to the first level, the combustion force of the reburning chamber burner is set to a high level, the reburning blower and the heating blower are stopped, and the sensor is 130 to 130 when carbonized. When a temperature of 140 ° C was detected, the combustion power of the heating chamber burner was set to the second level, the reburning blower and the heating blower were operated, and the sensor detected a temperature of 170 to 190 ° C during carbonization. At this time, the combustion force of the heating chamber burner is set to the third level, the combustion force of the reburning chamber burner is set to a low level, and the sensor detects a temperature of 300 to 330 ° C. during carbonization. , Setting the combustion power of the heating chamber burner to the second level, stopping the heating chamber burner when the carbonization of the object to be treated is completed, setting the combustion power of the reburning chamber burner to a high level, and stopping the heating chamber burner A predetermined time after that, the reburning chamber burner is stopped, and after a predetermined time after the reburning chamber burner is stopped, the reburning blower and the heating blower are stopped.