JPH0938618A - Treatment of shredder dust and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the corrosion of a device, to make shredder dust pollution-free, to reduce its volume and to recycle the dust by specifying respective dry distillation conditions in a method for subjecting the dust to low-temp. dry distillation and washing away the chlorine- components included in the residues of this low-temp. dry distillation, then subjecting the residues of the washing to high-temp. dry distillation. SOLUTION: The entire part of the treating device is composed of a low-temp. dry distillation system A, a washing system B and a high-temp. dry distillation system. The inside of the furnace body 12 of the low-temp. dry distillation device 10 is first maintained in a nonoxidizing atmosphere and, thereafter, the shredder dust 1 is charged from a charging system 11 into the furnace body and is dry distilled at a low temp. of 250 to 350 deg.C at the time of treating the shredder dust 1, by which the plastics are thermally decomposed and the chlorine is removed. Next, solid contents are captured in a dust collector 20 and the low-temp. dry distillation gas is subjected to water cooling and condensing in a condenser 30. The low-temp. dry distillation gas is scrubbed in a scrubber 50, by which the gaseous hydrogen chloride is completely removed. In succession, the residues of the low-temp. dry distillation are washed in a washing device 90 and, thereafter the residues of the washing are charged into a high-temp. dry distillation device 110 where the residues are subjected to the high-temp. dry distillation at 450 to 600 deg.C in the nonoxidizing atmosphere.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shredder dust processing method and apparatus for detoxifying, reducing the volume and recycling of shredder dust.

[0002]

2. Description of the Related Art There is a method for disposing of discarded automobiles, home electric appliances, etc. by dismantling recyclable parts by dismantling and then shearing and crushing them with a shredder device to produce shredder dust. The shredder dust is a mixture of plastic, rubber, fiber, glass, earth and sand, metal and the like, and particularly contains a large amount of polyvinyl chloride used as a covering material for wiring.

The majority of such shredder dust is currently disposed of in landfill.

[0004]

However, there is a problem in landfill disposal that it is difficult to secure a disposal site. Therefore, there is a demand for incineration treatment that can be expected to reduce the volume.

However, since a large amount of polyvinyl chloride is mixed in the shredder dust, if an ordinary incineration process, for example, an incineration process at 600 to 800 ° C. is carried out, the device using hydrogen chloride gas generated will be used. There is a problem that corrosion occurs.

The present invention has been made in view of the above circumstances, and dechlorination of the shredder dust is performed to prevent the occurrence of device corrosion, and the shredder dust is rendered harmless.
It is an object of the present invention to provide a shredder dust processing method and apparatus capable of reducing the volume and recycling.

[0007]

A method for treating shredder dust according to claim 1, wherein the shredder dust is obtained by a low temperature carbonization step of carbonizing the shredder dust in a non-oxidizing atmosphere at 250 ° C. or higher and 350 ° C. or lower, and the low temperature carbonization step. And a high temperature carbonization step of carbonizing the cleaning residue obtained by the cleaning step at 450 ° C. or more and 600 ° C. or less in a non-oxidizing atmosphere. I am trying. In the shredder dust processing method according to claim 2, claim 1
The shredder dust treatment method described above is characterized in that the high temperature dry distillation gas obtained in the high temperature dry distillation step is condensed to obtain a dry distillation liquid, and then the dry distillation liquid is separated into oil and water to obtain a dry distillation oil. A method for treating shredder dust according to a third aspect is characterized in that, in the method for treating shredder dust according to the second aspect, the high-temperature dry distillation gas from which the dry distillation liquid has been removed by the condensation operation is obtained as a fuel. In the method for treating shredder dust according to claim 4, in the method for treating shredder dust according to claim 1, 2 or 3, the high temperature carbonization residue obtained by the high temperature carbonization step is introduced into a smelting furnace to remove metal components. It is characterized by recovering and obtaining carbide as fuel.

In the apparatus for treating shredder dust according to claim 5, the shredder dust is charged, and the low temperature carbonization device for carbonizing the shredder dust at 250 ° C. or higher and 350 ° C. or lower is connected to the rear side of the low temperature carbonization device. A first gas cleaning means for cleaning the gas discharged from the low temperature carbonization device, and a gas connected to the rear side of the first gas cleaning means and cleaned by the first gas cleaning means. A first evacuation means for evacuating the gas, a cleaning means for cleaning the low-temperature carbonization residue generated in the low-temperature carbonization apparatus to form a cleaning residue, and the cleaning residue being charged to remove the cleaning residue by 4 times.
A high temperature carbonization device for carbonization at 50 ° C. or more and 600 ° C. or less; second gas cleaning means connected to the rear side of the high temperature carbonization device for cleaning gas discharged from the high temperature carbonization device; The second gas cleaning means connected to the rear side of the second gas cleaning means.
And a second exhaust means for exhausting the gas cleaned by the gas cleaning means. Claim 6
The shredder dust processing apparatus according to claim 5, wherein the gas discharged from the low temperature carbonization apparatus is connected between the low temperature carbonization apparatus and the first gas cleaning means. It is connected between the first condenser for condensing to generate a dry distillation liquid and discharging the remaining gas toward the first gas cleaning means, and the high temperature carbonization device and the second gas cleaning means. A second condenser for condensing the gas discharged from the high temperature carbonization device to generate a carbonized liquid and discharging the remaining gas toward the second gas cleaning means;
And an oil / water separation unit that is respectively connected to the second condenser and performs oil / water separation of the dry distillation liquid generated by the condenser. In the shredder dust processing apparatus according to claim 7,
Alternatively, in the shredder dust treatment device according to claim 6, one or both of the low-temperature carbonization device and the first gas cleaning device and the high-temperature carbonization device and the second gas cleaning device may be provided with A dust collecting means for collecting solids contained in the gas discharged from the low-temperature or high-temperature carbonization device is connected, and the first exhaust means and the second exhaust means are connected.
The first bubbling tank and the second bubbling are provided on the rear side of each of the exhaust means for bubbling the gas exhausted from the first exhaust means and the second exhaust means and then exhausting the gas to the rear side. A tank is connected, and an afterburner for heating gas discharged from the bubbling tank is connected to the rear side of the first bubbling tank.

[Operation] In the low temperature carbonization step, the chlorine content contained in the shredder dust is vaporized as hydrogen chloride gas. Further, a part of this hydrogen chloride gas is fixed in the low temperature dry distillation residue as a metal chloride. After that, in the washing step, the low temperature dry distillation residue is washed,
The chlorine content fixed in the low temperature carbonization residue was removed, and in the end,
Chlorine is removed from the shredder dust. The washing residue obtained by the washing process undergoes a high-temperature dry distillation process, causing thermally decomposable components in the wash residue to become high-temperature dry distillation gas and a high-temperature dry distillation residue with a small volume. Volume can be reduced. The high-temperature carbonization gas obtained by the high-temperature carbonization step contains oil, and the carbonization oil is obtained through the condensation process and the oil-water separation process, and the shredder dust can be recycled. Furthermore, the high-temperature dry distillation gas from which the dry distillation oil has been removed by the condensation operation is flammable and can be obtained as a fuel. When the high-temperature carbonization residue obtained by the high-temperature carbonization step is introduced into the smelting furnace, the metal components are recovered and carbides are obtained as fuel to further recycle the shredder dust.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows an embodiment of a shredder dust treating apparatus of the present invention, which is mainly composed of a low temperature carbonization system A, a cleaning system B and a high temperature carbonization system C.

The low temperature carbonization system A is a low temperature carbonization device 1.
0, a dust collector 20, a condenser 30, an oil / water separation tank 40, a scrubber 50, an exhaust fan 60, a bubbling tank 70, and an afterburner 80.

The low temperature carbonization apparatus 10 is composed of, for example, a rotary kiln, and is provided with a charging system 11 including a conveyor 11a and a double damper 11b, a furnace body 12, a carbonization residue discharge system 13, and an inert gas introducing section (not shown). It is a thing.

The dust collector 20 (dust collector) is, for example, a gravity settling type dust collector, which is connected to the rear side of the low-temperature carbonization device 10 and contains the low-temperature carbonization gas discharged from the low-temperature carbonization device 10. The solid content contained in is collected. The dust collector 20 is provided with a gas inlet 21 and a gas outlet 22 and an outlet 23 for the collected solids.

The capacitor 30 (first capacitor) is
For example, it is a water-cooled type, which is provided with a cooling pipe 32 in the casing 31 for water cooling, and is connected to the rear side of the dust collector 20. In addition to the gas inlet 33 and the gas outlet 34, the condenser 30 is provided with an outlet 35 for taking out a liquefied component liquefied by cooling / condensation of the low temperature carbonization gas discharged from the dust collector 20. There is.

The oil / water separation tank 40 (oil / water separation means) is connected to the outlet 35 of the condenser 30 and is for storing the liquefied component liquefied by condensation and separating it into oil and water. The oil separated here is stored in the oil storage tank 4
Stored in 1.

The scrubber 50 (first gas cleaning means) is
Which is connected to the gas outlet 34 of the condenser 30,
For example, a circulation facing type shower mechanism 51 is provided to perform alkali cleaning or water cleaning on the low temperature carbonization gas. The scrubber 50 is provided with a gas inlet 52 and a gas outlet 53.

The exhaust fan 60 (first exhaust means) is connected to the gas outlet 53 of the scrubber 50 and sucks low-temperature carbonization gas, so that the pressure in the furnace body 12 becomes a predetermined value. That is, the gas suction amount is controlled based on the pressure measured by the pressure sensor 14. The sucked low temperature carbonization gas is exhausted from the exhaust port 61.

Bubbling tank 70 (first bubbling tank)
Is connected to the exhaust port 61 of the exhaust fan 60, the low temperature carbonization gas flowing from the gas inlet 71 is bubbled by passing through the pool water 72, and then the gas outlet 7
Spill out of 3.

The afterburner 80 is a bubbling tank 7
It is connected to the gas outlet 73 of 0 and heats and burns the low temperature carbonization gas. Afterburner 80,
A demister 81 is provided before the input to dehumidify.

The cleaning device 90 (cleaning means) forming the cleaning system B is a device for cleaning metal chlorides with water to remove chlorine. The subsequent drying treatment may be performed in the sun or a drier.

The high temperature carbonization system C comprises a high temperature carbonization device 11
0, dust collector 120 (dust collector), condenser 130 (second condenser), oil water separation tank 140 (oil water separation means), scrubber 150 (second gas cleaning means), exhaust fan 160 (second exhaust gas) Means), a bubbling tank 170
(Second bubbling tank). These configurations correspond to the low temperature carbonization device 10 and the dust collector 2 respectively.
0, condenser 30, oil-water separation tank 40, scrubber 50,
It is similar to the exhaust fan 60 and the bubbling tank 70.

Next, with reference to FIGS. 1 and 2, an embodiment of a processing method using the shredder dust processing apparatus will be described.

The low temperature carbonization process A'is carried out by using the low temperature carbonization system A, and comprises a low temperature carbonization process S1, a condensation process S2, a gas cleaning process S3, and a heating process S4.

In the low temperature carbonization step S1, the shredder dust 1 is charged by the charging system 11 in a non-oxidizing atmosphere in which an inert gas such as nitrogen gas is introduced into the furnace body 12, and the low temperature of 250 ° C. to 350 ° C. It is carried out by dry distillation. In this step, the plastic contained in the shredder dust 1 is thermally decomposed to remove chlorine, and in particular, polyvinyl chloride is thermally decomposed to remove chlorine. Through this step, chlorine in the plastic, particularly chlorine in polyvinyl chloride, becomes hydrogen chloride gas and vaporizes. Part of this hydrogen chloride gas reacts with the metal in the shredder dust to form metal chloride. That is, the low-temperature carbonization gas contains hydrogen chloride gas, and the low-temperature carbonization residue is a solid content that does not cause thermal decomposition in this temperature range. It is chloride.

The temperature of the low temperature carbonization is preferably 250 ° C. or higher and 350 ° C. or lower. This is because, in this temperature range, the thermal decomposition of polyvinyl chloride sufficiently occurs, and the temperature of the entire system can be suppressed to such a low level that does not cause device corrosion due to hydrogen chloride gas. If the carbonization temperature is less than 250 ° C, the thermal decomposition of polyvinyl chloride may be insufficient, and the carbonization temperature will be 35%.
If the temperature exceeds 0 ° C., the temperature of the entire system becomes too high, which may cause device corrosion due to hydrogen chloride gas, which is not preferable.

Also in the dust collector 20, the solid content is collected and taken out from the outlet 23.
Similar to the low temperature dry distillation residue taken out from the dry distillation residue discharge system 13 of the low temperature dry distillation apparatus 10, it is treated as a low temperature dry distillation residue.

The condensing step S2 is performed in the condenser 30, water-cooling and condensing the low temperature dry distillation gas to remove the low boiling point gas, and liquefy with the water to obtain a dry distillation liquid. This dry distillation liquid is taken out together with water from the outlet 35 of the condenser 30, and oil / water separation is performed in the oil / water separation tank 40 to recover the dry distillation oil.

The gas cleaning step S3 is performed in the scrubber 50, and the low-temperature dry distillation gas is subjected to cleaning such as alkali cleaning and water cleaning to completely remove the hydrogen chloride gas in the low-temperature dry distillation gas.

The heating step S4 is performed in the afterburner 80 for the low temperature carbonization gas discharged from the scrubber 50 and passing through the exhaust fan 60 and the bubbling tank 70. The temperature of the low temperature carbonization gas is, for example, 1200 to 130.
By heating to about 0 ° C., combustible components such as carbon content contained in the low temperature carbonization gas are burned. At this time, the bubbling tank 70 is interposed between the exhaust fan 60 and the afterburner 80, whereby the flame on the rear side of the afterburner 80 is blocked from being transmitted to the front side (exhaust fan 60 side).

The cleaning process (cleaning step) B'is performed in the cleaning device 90 for the low temperature carbonization residue obtained from the low temperature carbonization device 10 and the dust collector 20.
Utilizing the fact that most of the metal chloride in the low temperature carbonization residue is water-soluble, the chlorine content is removed by, for example, washing with water, and the low temperature carbonization residue becomes a cleaning residue. Subsequently, the cleaning residue is dried in the sun or by a dryer.

Summarizing the processes up to this point focusing on the chlorine content, in the low temperature carbonization process A ', the chlorine content in the shredder dust becomes hydrogen chloride gas due to the thermal decomposition in the low temperature carbonization process S1, and the gas cleaning process S3. Is removed at. The hydrogen chloride gas fixed to the metal component in the shredder dust is removed by the cleaning in the cleaning process B ′. That is, dechlorination of shredder dust has been achieved in the processes described above.

The high temperature carbonization process C'is performed using the high temperature carbonization system C, and the high temperature carbonization process S6, the condensation process S7, the oil / water separation process S8, and the gas cleaning process S9 are performed.
It is composed of

The high temperature carbonization step S6 is carried out in the same manner as the low temperature carbonization step S1. The difference is that the feed material is a cleaning residue and the carbonization temperature. The dry distillation temperature is set to 450 ° C. or higher and 600 ° C. or lower. This is because in this temperature range, thermal decomposition of the plastic sufficiently occurs, and the temperature of the entire system is suppressed to such a low temperature that vaporization of the low melting point metal does not occur. If the dry distillation temperature is less than 450 ° C, the thermal decomposition of the plastic may be insufficient, and if the dry distillation temperature exceeds 600 ° C, the low melting point metal may be volatilized, which is not preferable. In this step, a gas containing a gasified carbon compound is obtained as the high-temperature carbonization gas, and a metal-containing carbide is left as the high-temperature carbonization residue.

In this high temperature carbonization step S6, since chlorine has already been removed, hydrogen chloride will not be generated and the equipment will not be corroded.

The solids are also collected in the dust collector 120, and thereafter, the solids are treated as a high temperature carbonization residue like the high temperature carbonization residue from the high temperature carbonization device 110. At this point, the plastic occupying most of the volume of the shredder dust is gasified as a high-temperature carbonization gas or left as a high-temperature carbonization residue, and the volume reduction is achieved.

The condensing step S7 is carried out in the condenser 130, where the high temperature dry distillation gas is water-cooled and condensed, and the carbon compounds having a low boiling point among the carbon components contained in the high temperature dry distillation gas are liquefied together with water to obtain a dry distillation liquid. To be This dry distillation liquid is taken out from the outlet of the condenser 130, sent to the oil / water separation tank 140, and provided for the oil / water separation step S8.

The oil / water separation step S8 is performed in the oil / water separation tank 140. In the oil / water separation tank 140, the oil and water are separated from the dry distillation liquid, and the separated oil, that is, the dry distillation reusable as fuel is carried out. Oil is stored in the oil storage tank 41.

The gas cleaning step S9 is performed in the scrubber 150, and the high temperature carbonization gas containing the high boiling point carbon compound which is not condensed in the condensation step S7 is subjected to cleaning such as alkali cleaning and water cleaning, The hot dry distillation gas is purified, and a combustible dry distillation gas (fuel) suitable for reuse is obtained.

Even when combustible dry distillation gas is burned as fuel in the rear side of the bubbling tank 170, the bubbling tank 170 is provided, so that the front side of the flame due to the combustible dry distillation gas (exhaust fan 160 side) Is cut off.

In the above high temperature carbonization process C ',
Dry distillation oil can be recovered by condensation of high temperature dry distillation gas and separation of oil and water, and clean combustible dry distillation gas with flammability can be obtained by containing carbon, and eventually shredder dust can be used as fuel (recycling). Has been achieved. In this case, the dry distillation oil is obtained also in the low temperature dry distillation process A ′, but the high temperature dry distillation process C ′ has a higher dry distillation oil recovery efficiency because of the difference in the dry distillation temperature.

On the other hand, by introducing the high temperature dry distillation residue into the smelting furnace, the metal component can be recovered.

The present invention is not limited to the above embodiment, but may be embodied as the following embodiments. (A) Use only one of the carbonization devices instead of using the low temperature carbonization device and the high temperature carbonization device, that is,
Dry-distillation at low temperature using shredder dust as input material, then cleaning the low-temperature dry-distillation residue by a cleaning means, and performing high-temperature carbonization with one of the carbonization devices as the input material. In this case, only one of the gas cleaning means and the exhaust means need be used, and the device cost can be reduced. (B) Use a device other than a rotary kiln as the low-temperature carbonization device 10. (C) As the dust collector 20, use a dust collector other than the gravity settling type. (D) Use a gas scrubber other than the scrubber 50, 150. (E) SOx, NOx behind the afterburner 80
To add a processing device such as.

[0044]

According to the shredder dust processing method and apparatus of the present invention, the following effects can be obtained. According to the method for treating shredder dust according to claim 1, in the low temperature carbonization step, the chlorine content contained in the shredder dust is removed by the gas cleaning means after being contained in the low temperature carbonization gas as hydrogen chloride gas, and The chlorine content of the hydrogen chloride gas, which becomes a metal chloride and is fixed in the low temperature dry distillation residue, can be removed in the cleaning step to achieve dechlorination of the shredder dust.
Furthermore, the washing residue that has undergone the washing process can be made into a high-temperature dry-distillation residue having a small volume by the high-temperature dry-distillation process, and the volume of shredder dust can be reduced. According to the method for treating shredder dust according to claim 2, after condensing the oil component in the high temperature carbonization gas obtained by the high temperature carbonization process, oil-water separation can be performed and recovered as carbonized oil, and the shredder dust can be recycled. Can be achieved. According to the method for treating shredder dust according to the third aspect, the high-temperature dry distillation gas from which the dry distillation oil has been removed by the condensation operation can be obtained as a fuel, and the shredder dust can be recycled. According to the method for treating shredder dust according to claim 4, by introducing the high temperature carbonization residue obtained by the high temperature carbonization step into the smelting furnace, the metal components are recovered and the shredder dust is further recycled. Can be achieved. According to the shredder dust treatment device of claim 5, a low temperature and high temperature carbonization device, first and second gas cleaning means, first and second exhaust means, and low temperature carbonization residue cleaning means are provided. Since it is provided, dechlorination and volume reduction of shredder dust can be achieved. According to the shredder dust processing apparatus of claim 6, since the condenser and the oil / water separation means are provided, the oil / water separation can be performed after the oil content in the dry distillation gas is condensed and recovered as the dry distillation oil. Recycling can be achieved. According to the shredder dust processing device of the seventh aspect, since the shredder dust has the dust collecting means, it is possible to prevent the dry distillation residue from being scattered to the rear side, so that the processing can be thoroughly performed. In addition, since it is equipped with an afterburner, it is possible to prevent the emission of carbon content. Further, since the bubbling tank is connected, the transmission of flame to the front side on the afterburner side located on the rear side can be blocked.

[Brief description of drawings]

FIG. 1 is an apparatus configuration diagram showing an embodiment of a shredder dust processing apparatus of the present invention.

FIG. 2 is a flow sheet showing an embodiment of a processing method using the shredder dust processing apparatus of the present invention.

[Explanation of symbols]

 1 Shredder dust 10 Low temperature carbonization device 20 Dust collector (dust collecting means) 30 Condenser (first condenser) 40 Oil-water separation tank (oil-water separation means) 50 Scrubber (first gas cleaning means) 60 Exhaust fan (first Exhaust means 70 Bubbling tank (first bubbling tank) 80 Afterburner 90 Cleaning device (cleaning means) 110 High temperature carbonization device 120 Dust collector (dust collecting means) 130 Condenser (second condenser) 140 Oil-water separation tank (oil-water separation) Means) 150 scrubber (second gas cleaning means) 160 exhaust fan (second exhaust means) 170 bubbling tank (second bubbling tank) S1 low temperature carbonization process B'cleaning process (cleaning process) S6 high temperature carbonization process

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasunari Ikeda 1-297 Kitabukuro-cho, Omiya-shi, Saitama Mitsubishi Materials Corporation

Claims (7)

[Claims] 1. A low-temperature carbonization step of dry-distilling shredder dust in a non-oxidizing atmosphere at 250 ° C. to 350 ° C., and a cleaning step of removing chlorine contained in the low-temperature carbonization residue obtained by the low-temperature carbonization step, And a high temperature carbonization step of carbonizing the cleaning residue obtained by the cleaning step in a non-oxidizing atmosphere at 450 ° C. or higher and 600 ° C. or lower, to treat shredder dust. 2. The shredder according to claim 1, wherein the high temperature carbonization gas obtained in the high temperature carbonization step is condensed to obtain a carbonization liquid, and then the carbonization liquid is separated into oil and water to obtain a carbonization oil. How to dispose of dust. 3. The method for treating shredder dust according to claim 2, wherein the high-temperature dry distillation gas from which the dry distillation liquid has been removed by the condensing operation is obtained as a fuel. 4. The shredder dust according to claim 1, 2 or 3, wherein the high temperature carbonization residue obtained in the high temperature carbonization step is introduced into a smelting furnace to recover metal components and obtain carbides as fuel. Processing method. 5. A low-temperature carbonization device which is charged with shredder dust and carbonizes the shredder dust at 250 ° C. or higher and 350 ° C. or lower, and a gas which is connected to the rear side of the low-temperature carbonization device and is discharged from the low-temperature carbonization device. First gas cleaning means for cleaning the first gas cleaning means, and first exhaust means connected to the rear side of the first gas cleaning means for discharging the gas cleaned by the first gas cleaning means, Cleaning means for cleaning the low temperature dry distillation residue generated in the low temperature dry distillation apparatus to obtain a cleaning residue;
A high temperature carbonization device for carbonization at a temperature of 00 ° C. or less, a second gas cleaning means connected to the rear side of the high temperature carbonization device for cleaning gas discharged from the high temperature carbonization device, and the second gas. A shredder dust treatment device, comprising: a second exhaust unit connected to the rear side of the cleaning unit to exhaust the gas cleaned by the second gas cleaning unit. 6. A gas which is connected between the low-temperature carbonization device and the first gas cleaning means and which is discharged from the low-temperature carbonization device is condensed to generate a carbonization liquid, and the remaining gas is mixed with the first gas. The first condenser discharged to the gas cleaning means, the high temperature carbonization device and the second gas cleaning means are connected to condense the gas discharged from the high temperature carbonization device to generate a carbonized liquid. A second condenser that discharges the remaining gas toward the second gas cleaning means, and an oil water that is connected to each of the first and second condensers and separates the dry distillation liquid produced by the condenser from oil water The shredder dust processing apparatus according to claim 5, further comprising a separating unit. 7. The low-temperature or high-temperature carbonization device is provided in one or both of the low-temperature carbonization device and the first gas cleaning device and between the high-temperature carbonization device and the second gas cleaning device. Dust collecting means for collecting the solid content contained in the discharged gas is connected, and the first exhaust means is provided on the rear side of each of the first exhaust means and the second exhaust means. And a first bubbling tank and a second bubbling tank for bubbling the gas discharged from the second exhaust means and then exhausting the gas to the rear side are connected to the rear side of the first bubbling tank. The shredder dust processing device according to claim 5 or 6, further comprising an afterburner connected to heat the gas discharged from the bubbling tank.