WO2007069449A1

WO2007069449A1 - Method and facility for the disposal of plastics waste

Info

Publication number: WO2007069449A1
Application number: PCT/JP2006/323665
Authority: WO
Inventors: Mitsuo Masunari; Yoshihiro Hamaguchi
Original assignee: Orient Instrument Computer Co., Ltd.
Priority date: 2005-12-12
Filing date: 2006-11-28
Publication date: 2007-06-21
Also published as: JP2009051867A

Abstract

The invention aims at reducing the volume of plastics wastes of various forms, particularly medical plastics waste containing a large amount of used bulky articles such as films or containers, nearly steadily and continuously and thereby recovering fuel oil efficiently. The invention relates to a disposal facility (1) for plastics waste which is provided with a volume reduction plant (2) and a pyrolysis plant (8). The volume reduction plant (2) is constituted of a treatment tank (3), a superheated steam feeder (4), and a screw feeder (5) for the treatment tank. The superheated steam feeder (4) is constituted of the first superheated steam feeder (4a) for feeding superheated steam into the treatment tank (3) and the second superheated steam feeder (4b) for feeding superheated steam to the inside of the shaft of the screw feeder (5) though the shaft tip and ejecting the superheated steam toward the outside of the shaft which is filled with the substance to be treated from the inside of the shaft. The substance to be treated is melted by the superheated steam ejected from the second superheated steam feeder (4b), fed into the pyrolysis plant (8), and gasified therein through pyrolysis. Thus, fuel oil is recovered.

Description

Specification

Method and apparatus for processing plastic waste

Technical field

TECHNICAL FIELD [0001] The present invention relates to a plastic waste processing method and processing apparatus. More specifically, the present invention can recover high-quality fuel waste plastic oil such as medical plastic waste containing many bulky containers. The present invention relates to a plastic waste processing method and processing apparatus.

Background art

Conventionally, used plastic waste has been either landfilled or incinerated. When landfilling, container-like waste is bulky, so a large landfill site is required to dispose of the waste that is discharged in large quantities. However, securing landfill sites has become difficult year by year, and it is virtually impossible to continue landfill disposal in the future.

On the other hand, in the case of incineration, about 10, the combustion of plastic having a high calorie OOOkcalZkg is required stoichiometric amount of air of about 12m ³ per LKG, yet is Oite the actual incineration 20 m ³ or more air Since it was used, there was a problem that the surrounding environment was greatly polluted. In addition, the remaining heat is hardly used at present, which is not preferable in terms of energy efficiency.

Also, in Japan, it is difficult to permit installation of small incinerators, making it unsuitable for the treatment of plastic waste that is widely dispersed, and there is a major problem that the risk of dioxin generation is always attached. I had it.

[0003] In view of such problems, many techniques for recovering fuel oil by converting plastic waste into pyrolysis oil have been proposed.

Many of the techniques proposed in the past employ a method in which melted plastic is introduced into a treatment tank and the treatment tank is heated also by an external force. (For example, see Patent Document 1 below).

[0004] However, in such a method, carbon accumulates in the treatment tank and inhibits heat conduction. The current situation is that it is difficult to drive for a long time.

Moreover, the external heating method has a heat dissipation of 40 to 60%, so the heat efficiency is very poor and it is not an economically good method.

[0005] As a technique created in view of such problems, there is a technique disclosed in Patent Document 2 below.

Patent Document 2 describes a volume reduction device for reducing the volume by spraying superheated steam on an object to be treated as plastic waste, superheated steam generating means for generating superheated steam, and volume reduction by the volume reduction device. A plastic waste treatment apparatus comprising: a thermal decomposition apparatus that accommodates the treated object inside and thermally decomposes by contacting with the superheated steam generated by the superheated steam generation means; The

[0006] This disclosed technique is a method in which superheated steam is introduced into a processing apparatus and the processing apparatus is heated from the inside, so that many of the problems of the external heating method described above can be solved. It was excellent.

However, in the disclosed technique of Patent Document 2, the plastic waste supplied into the volume reduction device is melted by the superheated steam supplied from the superheated steam generator, but the screw feeder As the temperature was lowered at the tip when it was transferred through, the fluidity was lowered and smooth transfer became difficult, and the process had to be temporarily stopped.

Therefore, it has been difficult for the processing apparatus disclosed in Patent Document 2 to continuously process various plastic wastes supplied in various forms.

Patent Document 1: Japanese Patent Laid-Open No. 6-41546

Patent Document 2: Japanese Patent Application Laid-Open No. 2004-359897

Disclosure of the invention

Problems to be solved by the invention

[0009] The present invention has been made in view of the above circumstances, and is a medical plastic that contains a large amount of plastic waste supplied in various forms, particularly bulky materials such as used film and containers. It is an object of the present invention to provide a plastic waste processing method and processing apparatus capable of reducing the volume of waste almost continuously and recovering it as fuel oil. Means for solving the problem

[0010] One aspect of the present invention includes the following steps (1) to (4):

(1) A process of containing a plastic waste to be treated in a treatment tank of a volume reduction device and bringing it into contact with superheated steam,

(2) A step of taking out the object to be processed melted in step (1) to the outside of the processing tank with a screw feeder for the processing tank,

(3) Step of supplying the object to be processed taken out in step (2) to a pyrolysis apparatus and heating and pyrolyzing it to obtain pyrolysis gas,

(4) The process of supplying the pyrolysis gas obtained in step (3) to the condenser and liquefying it to recover the oil,

In the step (2), the force of the tip of the shaft provided in the screw feeder for the processing tank is separately supplied with superheated steam to the inside of the shaft. This is a plastic waste treatment method in which the material to be treated is ejected toward the outside of the shaft and superheated steam is brought into contact with the material to be treated.

[0011] This aspect relates to a method for treating plastic waste, and includes the above steps (1) to (4). In the method for treating plastic waste of this aspect, in step (2), the tip force of the shaft provided in the screw feeder for the treatment tank is supplied separately to the inside of the shaft, and superheated steam is filled from the inside of the shaft with the treatment object. It is ejected to the outside of the shaft, and superheated steam is brought into contact with the workpiece. In this aspect of the plastic waste processing method, the force at the tip of the shaft is also supplied to the inside of the shaft to the screw feeder for the processing tank that transfers the object to be processed melted by the superheated steam in the volume reduction device. Since jetting is performed from the inside of the shaft toward the outside of the shaft that is filled with the object to be processed, the temperature of the object to be processed may be lowered at the tip of the screw feeder for the processing tank, resulting in a decrease in fluidity. Is prevented. Therefore, it is possible to continuously process various plastic wastes supplied in various forms, especially medical plastic wastes containing a lot of bulky films and containers.

The “tip portion of the shaft” includes both a tip portion located on the discharge port side and a tip portion located on the inlet side of the processing tank screw feeder. [0013] Preferably, the distal end portion of the shaft is located on a discharge port side of the processing tank screw feeder.

[0014] According to this preferable aspect, it is possible to more reliably prevent a temperature drop of the object to be processed at the tip portion of the screw feeder for the processing tank.

[0015] Preferably, the superheated steam supplied from the tip of the shaft has a higher pressure than the superheated steam supplied into the processing tank.

[0016] In this preferable aspect, the superheated steam that also supplies the force at the tip of the shaft of the screw feeder for the processing tank has a higher pressure than the superheated steam supplied into the storage tank. By virtue of the powerful structure, the superheated steam can be reliably brought into contact with the object to be processed in the screw feeder, and the molten resin can be transferred very smoothly.

[0017] Preferably, the step (3) further includes a step of taking out a thermal decomposition residue generated by the thermal decomposition to the outside with a thermal feeder for a thermal decomposition apparatus, and in this step, the screw feeder for the thermal decomposition apparatus is Force of the tip of the shaft provided Superheated steam is supplied to the inside of the shaft, ejected from the inside of the shaft toward the outside of the shaft filled with pyrolysis residue, and superheated steam is brought into contact with the pyrolysis residue.

[0018] In this preferable aspect, the method further includes a step (3) of taking out the thermal decomposition residue generated by the 1S thermal decomposition to the outside with a screw feeder for a thermal decomposition apparatus. In this process, superheated steam is supplied into the shaft of the thermal cracker screw feeder. With this configuration, the temperature inside the screw feeder for the pyrolysis device is prevented from lowering, and the pyrolysis residue can be continuously taken out and processed. Here, the “tip portion of the shaft” includes both a tip portion located on the discharge port side and a tip portion located on the inlet side of the screw feeder for the thermal decomposition apparatus.

[0019] Preferably, the pyrolysis gas to be condensed discharged from the condenser in the step (4) is taken into the deodorizer and burned by the burner, and the high-temperature gas generated in the deodorizer is heat-exchanged. Water is converted to steam, and the steam generated by the heat exchanger is superheated to supply superheated steam to be supplied into the volume reducing device, superheated steam to be supplied to the screw feeder for the processing tank, and It is used as at least one superheated steam selected from the group consisting of superheated steam supplied to the screw feeder for pyrolysis equipment. [0020] In this preferable aspect, in order to generate superheated steam to be supplied into the volume reduction device, superheated steam to be supplied to the screw feeder for the treatment tank, or superheated steam to be supplied to the screw feeder for the thermal decomposition device, Since it is possible to use the high-temperature gas generated inside the deodorizing device, it is possible to effectively use thermal energy. The superheated steam to be used can be any one of superheated steam supplied to the volume reduction device, superheated steam supplied to the screw feeder for the treatment tank, and superheated steam supplied to the screw feeder for the thermal decomposition device. It's okay or two or more.

[0021] Here, "superheated steam supplied to the processing tank screw feeder" means superheated steam supplied from the tip of the shaft provided in the processing tank screw feeder to the inside of the shaft. Similarly, “superheated steam to be supplied to the pyrolysis device screw feeder” means superheated steam supplied to the inside of the shaft of the shaft provided in the screw feeder for the thermal decomposition device.

[0022] Another aspect of the present invention includes a processing tank for storing a processing object made of plastic waste, and a superheated steam supply device for supplying superheated steam to the processing object stored in the processing tank. And a volume reducing device having a processing tank screw feeder for taking out the processing object melted by contact with the superheated steam supplied from the superheated steam supply apparatus to the outside of the processing tank, and supplying the superheated steam supply The apparatus supplies the superheated steam to the inside of the first superheated steam supply device for supplying superheated steam into the processing tank and the shaft force shaft of the shaft provided in the processing tank screw feeder. This is a plastic waste treatment device having a second superheated steam supply device that ejects the shaft filled with the treatment material toward the outside.

[0023] This aspect relates to a plastic waste processing apparatus, a processing tank for storing a processing object made of plastic waste, and superheated steam for the processing object stored in the processing tank. A volume reduction device having a superheated steam supply device for supplying the processing tank, and a processing tank for the processing tank for taking out the processing object melted by contact with the superheated steam supplied from the superheated steam supply device to the outside of the processing tank. To do. Further, in the plastic waste processing apparatus of this aspect, the superheated steam supply device has a first superheated steam supply device and a second superheated steam supply device. And the 1st superheated steam supply device is a processing tank. The second superheated steam supply device supplies the superheated steam to the inside of the shaft of the shaft provided in the processing tank sta- ble feeder, and the workpiece from the inside of the shaft. Is ejected toward the outside of the shaft filled with In the plastic waste processing equipment of this aspect, superheated steam is supplied from the tip of the shaft to the inside of the shaft to the screw feeder for the processing tank that transfers the material melted by the superheated steam in the volume reduction device. Since the shaft is filled with the object to be processed and can be ejected toward the outside of the shaft, the temperature of the object to be processed decreases at the tip of the screw feeder for the processing tank, and the fluidity may decrease. Is prevented. Therefore, it is possible to continuously process various plastic wastes supplied in various forms, particularly medical plastic wastes containing a lot of bulky films and containers.

[0024] Preferably, the second superheated steam supply device can supply superheated steam at a higher pressure than the first superheated steam supply device.

In this preferable aspect, the second superheated steam supply device can supply superheated steam at a higher pressure than the first superheated steam supply device. By virtue of the powerful structure, the superheated steam can be reliably brought into contact with the object to be processed in the screw feeder for the processing tank, and the molten resin can be transferred very smoothly.

[0026] Preferably, a thermal decomposition apparatus having a storage tank for taking in an object to be processed taken out by the processing tank screw feeder and thermally decomposing it, and taken out from the thermal decomposition apparatus A dehalogenation device incorporating a metal catalyst that takes in a pyrolysis gas and removes halogen components contained in the gas, and a condenser that takes in the gas that has passed through the dehalogenation device and liquefies it. The pyrolysis apparatus has a pyrolysis apparatus screw feeder for taking out pyrolysis residue to the outside, and the superheated steam supply apparatus superheats steam from the tip end of the shaft included in the pyrolysis apparatus screw feeder to the inside of the shaft. And can be ejected from the inside of the shaft toward the outside of the shaft filled with the pyrolysis residue.

[0027] The processing apparatus of this preferred aspect includes a thermal decomposition apparatus having a storage tank for taking in an object to be processed extracted by a processing tank screw feeder and thermally decomposing it. The thermal decomposition apparatus is a thermal decomposition apparatus for taking out the thermal decomposition residue to the outside. The superheated steam supply device is equipped with a screw feeder for installation, and the tip portion of the shaft provided in the screw feeder for the pyrolysis device supplies superheated steam to the inside of the shaft and is filled with pyrolysis residue from the inside of the shaft. It can be ejected toward the outside of the shaft. With this configuration, the temperature inside the screw feeder for the thermal decomposition apparatus is prevented from being lowered, and the thermal decomposition residue can be continuously taken out and processed.

[0028] Further, the processing apparatus of this aspect preferably includes a dehalogenation apparatus and a capacitor. With this configuration, it is possible to dehalogenate the pyrolyzed gasification object and to improve the decomposition properties of the recovered fuel oil.

[0029] Preferably, the deodorizing device that takes in the condensed pyrolysis gas discharged from the condenser force and burns it with a burner, and heat that converts water into steam using the high-temperature gas generated inside the deodorizing device. And a steam supply passage for supplying the steam generated by the heat exchanger to the superheated steam supply device in order to turn the steam generated by the heat exchanger into superheated steam.

[0030] In this preferable aspect, steam is generated using the high-temperature gas generated inside the deodorizing apparatus, and the steam is supplied to the superheated steam supply apparatus, so that the thermal energy can be effectively used. The steam supplied to the superheated steam supply device may be supplied to the first superheated steam supply device, the second superheated steam supply device, or to the third superheated steam supply device. It may be supplied. Also, not only one of these but also two or more may be supplied.

[0031] Preferably, the treatment tank of the volume reduction device and the storage tank of the thermal decomposition device are made of metal, and ceramics are welded to the inside thereof.

[0032] According to this preferable aspect, damage due to heat and corrosion of the treatment tank of the volume reduction device and the storage tank of the pyrolysis device can be prevented, and the operation can be continued for a long period of time. Become.

The invention's effect

[0033] According to the plastic waste processing method of the present invention, it is possible to prevent the fluidity from being lowered due to the temperature of the processing object being lowered at the tip of the processing tank screw feeder. Therefore, it is possible to continuously process various plastic wastes supplied in various forms, especially medical plastic wastes containing a lot of bulky films and containers. Become.

[0034] The same applies to the plastic waste processing apparatus of the present invention, and various plastic wastes can be continuously processed. Brief Description of Drawings

FIG. 1 is a schematic view showing a configuration of a plastic waste processing apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an internal structure of a screw feeder for a processing tank.

FIG. 3 is a cross-sectional view showing an internal structure of a screw feeder for a thermal decomposition apparatus.

Explanation of symbols

[0036] 2 Volume reduction device

3 Treatment tank

4 Superheated steam supply device

4a First superheated steam supply device

4b Second superheated steam supply device

5 Screw feeder for processing tank

7 Metal catalyst device (dehalogenation device)

8 Pyrolysis device

9 Screw feeder for pyrolysis equipment

10 Containment tank

14 capacitors

19 Deodorizer

20 heat exchanger

22 burner

43 Steam supply path

51 shaft

56 Tip

61 Processing equipment (Plastic waste processing equipment)

91 shaft BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the plastic waste processing method and processing apparatus of the present invention will be described with reference to the drawings as appropriate.

In the plastic waste processing method and processing apparatus of the present invention, the plastic waste to be treated is a container-like or film-like waste made of thermoplastic resin, and specifically, medical waste. Goods (eg, infusion containers, chemical containers, syringe cylinders, chemical bags, etc.) are suitable treatment targets.

A processing device 61 shown in FIG. 1 is a plastic waste processing device, and includes a volume reduction device 2 and a thermal decomposition device 8. When processing plastic waste such as medical waste made of thermoplastic resin (hereinafter referred to as “processed object”) with the processing device 61, the process object is placed in the loading container 1 and lifted ( For example, it is lifted by a lifting type equipment as shown in FIG.

[0039] The volume reduction device 2 includes a treatment tank 3 that accommodates an object to be treated, a superheated steam supply device 4 that supplies superheated steam to the object to be treated contained in the treatment tank 3, and the superheater. It consists of a processing tank screw feeder 5 for taking out the object to be processed melted by contact with superheated steam supplied from the steam supply device 4 to the outside of the processing tank 3.

[0040] The superheated steam supply device 4 includes a first superheated steam supply device 4a and a second superheated steam supply device 4b. The first superheated steam supply device 4 a is provided below the processing tank screw feeder 5 and supplies superheated steam into the lower force processing tank 3 of the processing tank screw feeder 5. That is, the first superheated steam supply device 4a is used in the above-described step (1). On the other hand, the second superheated steam supply device 4b is directed from the outlet tip of the treatment tank screw feeder 5 (tip on the discharge port side) through the shaft 51 toward the center of the treatment tank screw feeder 5. Superheated steam is supplied and ejected from the inside of the shaft 51 toward the outside of the shaft 51 filled with the workpiece. That is, the treatment tank screw feeder 5 and the second superheated steam supply device 4b are used in the aforementioned step (2).

As shown in FIG. 2, the processing tank screw feeder 5 includes a shaft 51 having a screw and a casing 50 surrounding the shaft 51. Inside of shaft 51 is one of them A superheated steam introduction space 55 extending from the tip 56 to the vicinity of the center is formed. The tip 56 is open and functions as a superheated steam inlet 52 communicating with the superheated steam introduction space 55. Furthermore, a plurality of superheated steam jets 53 communicating with the superheated steam introduction space 55 are provided on the surface of the shaft 51.

During operation of the processing tank screw feeder 5, the object to be processed fills the gap between the shaft 51 and the casing 50, and is transferred from the processing tank 3 to the tip 56 in the direction of the force. That is, the tip 56 is located on the discharge port side of the workpiece.

In the present embodiment, superheated steam is supplied from the superheated steam inlet 52 when the workpiece is transferred. Then, the superheated steam is taken into the shaft 51 from the superheated steam inlet 52 and guided toward the proximal end of the shaft 51. In other words, the supplied superheated steam proceeds toward the central portion inside the shaft 51, and the superheated steam introduction space 55 is filled with the superheated steam. The superheated steam taken into the shaft 51 (that is, the superheated steam introduction space 55) is jetted out of the shaft 51 through a plurality of superheated steam outlets 53 provided in the shaft 51. In other words, superheated steam is ejected toward the gap between the shaft 51 and the casing 50. As a result, the object to be processed that fills the gap between the shaft 51 and the casing 50 near the discharge port of the screw feeder 5 for the processing tank (that is, near the tip 56 of the shaft 51) is heated by the superheated steam. Thus, the molten state is reliably maintained up to the discharge port, and continuous and smooth transfer can be performed.

In this embodiment, the superheated steam inlet 52 is provided at the tip 56 located on the discharge outlet side of the workpiece, but the superheated steam inlet is provided at the tip on the inlet side of the workpiece. Implementations are possible.

[0043] The superheated steam supplied from the first superheated steam supply device 4a into the treatment tank 3 is dissolved in the treatment object by contacting the treatment object accommodated in the treatment tank 3, thereby reducing the volume. The dissolved object to be processed is taken out by the processing tank screw feeder 5 and supplied to the thermal decomposition apparatus 8.

[0044] The temperature of the superheated steam supplied from the first superheated steam supply device 4a into the treatment tank 3 and the temperature of the superheated steam supplied from the second superheated steam supply device 4b to the screw feeder 5 for the treatment tank are It is set to about 500 ° C to 550 ° C. The second superheated steam supply device 4b is configured to supply superheated steam at a higher pressure than the first superheated steam supply device 4a!

[0045] The thermal decomposition apparatus 8 is used in the above-mentioned step (3), and the storage tank 10 for taking in the object to be processed supplied by the screw feeder 5 for the processing tank and thermally decomposing it. And a screw feeder 9 for a thermal decomposition apparatus for taking out thermal decomposition residues (medical injection needles, glass, metals and decomposition residues) to the outside. Then, superheated steam is supplied toward the center of the pyrolyzer screw feeder 9 through the inside of the shaft 91 at the tip of the screw feeder 9 for the pyrolyzer, and the workpiece is filled from the inside of the shaft. It is possible to eject the shaft 9 toward the outside. In FIG. 1, the second superheated steam supply device 4b described above is used when superheated steam is supplied to the shaft 91. However, a third superheated steam supply device may be separately provided and used. .

As shown in FIG. 3, the screw feeder 9 for a thermal decomposition apparatus includes a shaft 91 having a screw and a casing 90 surrounding the shaft 91. Inside the shaft 91, a superheated steam introduction space 95 is formed from the tip end 96 of the shaft 91 to the vicinity of the center. The tip 96 is open and functions as a superheated steam inlet 92 communicating with the superheated steam introduction space 95. Further, a plurality of superheated steam jets 93 communicating with the superheated steam introduction space 95 are provided on the surface of the shaft 91.

During operation of the screw feeder 9 for the pyrolysis device, the pyrolysis residue fills the gap between the shaft 91 and the casing 90 and is transferred from the storage tank 10 toward the power side (base end side) (leftward in FIG. 1). The That is, the tip 96 is located on the side opposite to the workpiece outlet.

In the present embodiment, superheated steam is supplied from the superheated steam inlet 92 when transferring the pyrolysis residue. Then, the superheated steam is introduced into the shaft 91 from the superheated steam inlet 92 and guided toward the proximal end of the shaft 91. In other words, the supplied superheated steam proceeds toward the central portion of the shaft 91, and the superheated steam introduction space 95 is filled with superheated steam. The superheated steam taken into the shaft 91 (that is, the superheated steam introduction space 95) is filled. Is ejected from the plurality of superheated steam outlets 93 provided in the shaft 91 to the outside of the shaft 91. To do. In other words, superheated steam is jetted toward the gap between the shaft 91 and the casing 90. As a result, the thermal decomposition residue that fills the gap between the shaft 91 and the casing 90 in the vicinity of the tip of the screw feeder 9 for the thermal decomposition apparatus (that is, in the vicinity of the tip 96 of the shaft 91) is heated by the superheated steam. Thus, it is smoothly transferred and continuously discharged from the rotary valve 11 provided at the power side (base end side) outlet of the thermal cracker screen feeder 9 to the residue receiver 39.

[0047] The superheated steam taken into the shaft 91 of the pyrolysis device screw feeder 9 is supplied to both the upper opening partial force of the casing 90 of the pyrolysis device screw feeder 9 and the inside of the storage tank 10, and the storage tank The object to be processed supplied inside 10 is pyrolyzed.

[0048] Above the storage tank 10 of the pyrolysis apparatus 8, a metal catalyst (such as iron oxide) for dehalogenating the pyrolyzed gasification object and reforming the decomposition properties of the recovered fuel oil. ), And an explosion-proof valve 13 that also serves as the take-out / take-in port for the metal catalyst device 7.

[0049] The treatment tank 3 of the volume reduction apparatus 2 and the storage tank 10 of the thermal decomposition apparatus 8 are made of metal, and heat-resistant and corrosion-resistant ceramics are welded inside! RU

As a result, the treatment tank 3 and the storage tank 10 are prevented from being damaged by heat and corrosion, and the operation can be continued for a long period of time.

[0050] The pyrolysis gas taken out from the pyrolysis device 8 through the metal catalyst device 7 is supplied to the capacitor 14 to be liquefied (the above-mentioned step (4)).

The condenser 14 includes a temperature adjusting device 15 that automatically controls the temperature of the off-gas temperature sensor 17 by catching the temperature of the off gas temperature sensor 17 and a nozzle 12 that sprays water in a fine mist form. In addition, a recovery tank 18 for recovering the regenerated fuel oil that has been liquefied is provided at the lower portion, and a liquid level gauge 16 is provided in the recovery tank 18.

[0051] The recovery tank 18 is connected to a fuel oil recovery pump 25 that operates when the liquid level detected by the liquid level gauge 16 exceeds a certain level, and the oil transferred by the fuel oil recovery pump 25 is To the three-phase separation centrifuge 23.

The oil separated by the centrifugal separator 23 is sent to the fuel tank 24, and the separated water is supplied to the vicinity of the burner 22 in the deodorizing device 19 and forcibly vaporized. Sent to sludge tank 37.

[0052] The deodorizing device 19 can take the gas to be condensed after the fuel oil is recovered in the condenser 14 into the inside and burn it by the burner 22 installed in the lower part inside. The deodorizer 19 includes a heat exchanger 20 that converts water into steam using the high-temperature gas generated in the deodorizer 19 when heated by the burner 22, and a secondary to assist combustion by the burner 22. And a metal combustion auxiliary device 21 for high-temperature complete combustion.

[0053] The heat exchanger 20 converts the water supplied from the water inlet 40 into steam having a pressure within lkgZcm ² , and this steam is supplied to the second superheated steam supply device 4b via the steam supply path 43. The

[0054] The steam supplied to the second superheated steam supply device 4b is heated by the burner 28 when it flows through the in-furnace coil-type heat exchanger 27 provided therein, so that the high-temperature superheated steam (500 It is supplied from the superheated steam outlet 29 via the superheated steam passages 30 and 31 to the processing tank screw feeder 5 and the thermal cracker screw feeder 9 respectively.

[0055] Combustion off-gas generated by the burner 28 in the second superheated steam generator 4b is introduced into the combustion gas inlet 34 below the pyrolysis device 8 via the combustion off-gas path 33, and the heat decomposition device 8 is introduced from the bottom. Can be heated. This makes it possible to effectively use thermal energy, and the exhaust gas is processed in a deodorizing furnace 19. On the other hand, a part of the combustion off-gas is branched and introduced into the inside from the combustion gas inlet 35 at the lower part of the volume reduction device 3 and used as a heat source.

[0056] The volume reduction device 3 may be filled with bad odors when the workpiece is melted. Therefore, this is taken out by the blower 36 and guided to the inside of the deodorizing device 19, and the deodorizing device 19 The exhaust gas after the high temperature treatment and the treatment is discharged from the exhaust pipe 38.

[0057] In the treatment apparatus 61 of the present embodiment, the screw feeder 9 for the thermal decomposition apparatus in the thermal decomposition apparatus 8 even when a medical infectious waste that can become a special industrial waste is mixed in the object to be processed. Because the pyrolysis residue is completely sterilized by the high-temperature superheated steam (over 500 ° C) ejected from the superheated steam outlet 93, it is no longer a special industrial waste.

The sterilized pyrolysis residue is discharged as industrial waste and collected in the residue receiver 39, but the metals and glasses contained in it can be separated and reused effectively. The

Industrial applicability

INDUSTRIAL APPLICABILITY The present invention can be suitably used for recovering high-quality medical plastic waste power fuel oil containing a large amount of bulky containers and films.

Claims

Claims [1] The following steps (1) to (4):

In the step (2), the force of the tip of the shaft provided in the screw feeder for the processing tank is separately supplied with superheated steam to the inside of the shaft. A plastic waste treatment method in which the material to be treated is ejected toward the outside of the shaft and superheated steam is brought into contact with the material to be treated.

2. The processing method according to claim 1, wherein a tip end portion of the shaft is located on a discharge port side of the processing tank screw feeder.

[3] The processing method according to claim 1 or 2, wherein the superheated steam supplied from the tip of the shaft is set to a pressure higher than that of the superheated steam supplied into the processing tank.

[4] The step (3) further includes a step of taking out a thermal decomposition residue generated by the thermal decomposition to the outside with a screw feeder for a thermal decomposition device, and in this step, a shaft of the shaft included in the thermal feeder for the thermal decomposition device 4. Tip force Supplying superheated steam to the inside of the shaft, ejecting it from the inside of the shaft toward the outside of the shaft filled with pyrolysis residue, and bringing the superheated steam into contact with the pyrolysis residue. The processing method as described in.

[5] In the step (4), the pyrolyzed gas to be condensed which has also been discharged from the condenser is introduced into the deodorizer and burned by a burner, and the high temperature gas generated in the deodorizer is transferred to the heat exchanger. The water is converted into steam, the steam generated by the heat exchanger is superheated, superheated steam supplied into the volume reducing device, superheated steam supplied to the screw feeder for the processing tank, and the thermal decomposition Superheated steam power supplied to the screw feeder for equipment 5. The treatment method according to claim 4, wherein the treatment method is used as at least one superheated steam selected from the group

[6] A processing tank for storing a processing object made of plastic waste, a superheated steam supply device for supplying superheated steam to the processing object stored in the processing tank, and the superheated steam supply device A volume reducing device having a processing tank screw feeder for taking out the object to be processed melted by contact with the supplied superheated steam to the outside of the processing tank, and the superheated steam supply device is heated in the processing tank. The first superheated steam supply device that supplies steam and the tip force of the shaft provided in the processing tank screw feeder Supply superheated steam to the inside of the shaft, and fill the workpiece from the inside of the shaft to the outside of the shaft A plastic waste treatment device having a second superheated steam supply device that is ejected toward the surface.

7. The processing apparatus according to claim 6, wherein the second superheated steam supply device can supply superheated steam at a higher pressure than the first superheated steam supply device.

[8] A thermal decomposition apparatus having a storage tank for taking in an object to be processed which has also been taken out by the processing tank screw feeder and thermally decomposing it, and a thermal decomposition taken out from the thermal decomposition apparatus A dehalogenation device incorporating a metal catalyst that removes a halogen component contained in the gas by taking in the gas, and a capacitor that liquefies the gas that has passed through the dehalogenation device. The apparatus has a pyrolysis device screw feeder for taking out the pyrolysis residue to the outside, and the superheated steam supply device supplies the superheated steam to the inside of the shaft of the shaft provided in the pyrolysis device screw feeder. 8. The processing apparatus according to claim 6, wherein the processing apparatus is capable of ejecting from the inside of the shaft toward the outside of the shaft filled with pyrolysis residue.

[9] A deodorizer that takes in the pyrolyzed gas to be condensed discharged from the condenser and burns it with a burner, and converts water into steam using a high-temperature gas generated inside the deodorizer 9. The processing apparatus according to claim 8, further comprising: a heat exchanger; and a steam supply path that supplies the steam generated by the heat exchanger to the superheated steam supply apparatus so that the steam is generated as superheated steam.

10. The processing apparatus according to any one of claims 6 to 9, wherein the processing tank of the volume reduction device and the storage tank of the thermal decomposition apparatus are made of metal, and ceramics are welded to the inside thereof.