JPH10245567A - Treatment apparatus for waste plastic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a treatment apparatus adapted so that e.g. a treatment for converting mixed waste plastics into an oil may be continuously performed without pretreatment such as dehydrochlorination. SOLUTION: This apparatus is provided with a preliminary reactor 1 for performing a pretreatment such as dehydrochlorination and a main reactor 2 for performing oil conversion treatment, etc., contiguous to the reactor 1. The reactor 1 is provided with a reaction section 11 for subjecting waste plastics or the like to a reaction such as dehydrochlorination by heating them in the course of their descension along a conical heating surface 14 to convert them into a product of pretreatment, agitating means 15a and 15b for agitating the waste plastics on the heating surface, a transferring section 12 contiguous to the reaction section and a discharging section 20 for delivering the product of pretreatment from the section 12 to the reactor 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for treating waste plastics, and more particularly to a waste plastics mixed with plastics which release hydrogen chloride or cyan by heating such as polyvinyl chloride, ABS resin or polyacrylonitrile. The present invention relates to a processing apparatus capable of continuously performing an oiling process, a fuel gasifying process, and the like to a preliminary process such as dehydrochlorination.

[0002]

2. Description of the Related Art Waste plastics include oily plastics represented by polyethylene and polystyrene, and non-oilable plastics represented by polyvinyl chloride and polyethylene terephthalate. Is much larger. Therefore, it can be said that it is the most desirable method for treating waste plastic to convert waste plastic into oil at a reasonable cost for recycling.

[0003] However, in practice, the technology of turning waste plastic into oil at a reasonable cost has not yet been put to practical use.
There are two main causes. One of them concerns the liquefaction itself. For example, a large amount of carbon is generated during oily cracking, so that control of oily cracking, particularly control of the cracking temperature, cannot be performed effectively, and an oily product having a desired composition cannot be efficiently recovered. For this reason, it is not possible to perform oiling treatment at a reasonable cost. Regarding this, the present inventor has already proposed one of the solutions as Japanese Patent Application No. 6-324855.

[0004] Another problem is a problem in the case of treating a mixed waste plastic mixed with polyvinyl chloride or the like. Polyvinyl chloride releases hydrogen chloride upon heating, and this hydrogen chloride significantly shortens the life of the treatment equipment, especially the main component of oil treatment reactors, which account for a large proportion of the total equipment cost. This greatly increases the cost of oiling treatment and the like. Therefore,
In the case of mixed waste plastics, it is necessary to perform a preliminary treatment such as dehydrochlorination prior to the oiling treatment. The efficiency of the pretreatment has a considerable effect on the cost of the entire treatment such as oiling.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been developed so that the oily treatment of mixed waste plastics can be performed continuously with the preliminary treatment such as dehydrochlorination. In particular, it is an object of the present invention to provide a processing apparatus capable of efficiently performing a preliminary treatment prior to an oiling treatment.

[0006]

The processing apparatus according to the present invention comprises a pre-reactor and a main reactor. After performing pre-treatment such as dehydrochlorination in the pre-reactor, it is continuously connected to the main reactor. It basically has a structure that performs oiling treatment and the like. The pre-reactor has a mortar-shaped heating surface that is inclined downward toward a communication hole provided in the center, and the waste plastic is heated while flowing down the waste plastic along the heating surface. A reaction section which causes a reaction such as hydrogen to be a pre-processed product, a stirring means for stirring waste plastic on a heating surface of the reaction section, connected to the reaction section via the communication hole, and flows down the heating surface. It has a transfer unit for receiving incoming pre-processed products and transferring the pre-processed products by a built-in transfer means, and a sending unit for sending out the pre-processed products from the transfer unit and supplying the pre-processed products to the main reactor.

The mortar-shaped heating surface in the prereactor of such a processing apparatus can be heated in a state in which the waste plastic is made in a thin layer and is directly adhered to the heating surface, and the heating efficiency is high. Also, it is excellent in releasing gas generated by dehydrochlorination and the like. The stirring means also helps the waste plastic to contact the heating surface efficiently,
It helps to separate and separate gases and carbides generated by dehydrochlorination from waste plastics. For this reason, a reaction such as dehydrochlorination can be efficiently generated in the preliminary reactor of the present invention.

Further, the pre-reactor in the present invention has a transfer section, and a pre-processed product having undergone dehydrochlorination or the like is supplied to the main reactor via this transfer section.
For this reason, the supply amount of the pretreatment material to the main reactor can be quantified. This makes it easier to control oily cracking and the like in the main reactor and leads to efficient recovery of oily substances having a desired composition.

Further, the pre-reactor according to the present invention utilizes the chlorine generated by dehydrochlorination to form a metal chloride,
It functions more effectively when this metal chloride is used as a catalyst for oily cracking in the main reactor. For example, chlorides of metals such as aluminum, iron, tin, and zinc are effective catalysts for oily decomposition and fuel gasification of plastics. Therefore, these metals are mixed into waste plastics to carry out dehydrochlorination. At this time, metal chlorides are formed, and these are used as such as catalysts for oily cracking to achieve more rational and efficient treatment. can do.

In the case of such an oiling method, the pre-reactor according to the present invention heats the waste plastic while stirring it in a thin layer state, so that the metal chloride can be more efficiently used. Can be generated. In addition, since the pre-processed material is transported in the transfer unit by the transport means, during this time, the chlorine remaining in the pre-processed product is further reacted with the metal to promote the production of metal chlorides. In addition, the generated metal chloride can be uniformly dispersed in the pre-treated material, and the catalytic effect can be exhibited more efficiently.

The above-mentioned pre-reactor may be further provided with a transfer section thereof and a non-liquefied component recovery section for separating and collecting non-liquefied components from the pre-processed material. In this way, it is possible to efficiently treat waste plastic mixed with non-degradable plastic.

The above-mentioned preliminary reactor is used not only as a part of a waste plastic decomposition treatment apparatus but also as a dehydrochlorination apparatus for performing a dehydrochlorination treatment prior to a waste plastic incineration treatment, for example. be able to. In other words, incineration of waste plastics containing chlorine-containing plastics such as polyvinyl chloride has problems such as the generation of highly toxic dioxins. It is preferable to carry out dehydrochlorination prior to incineration. The prereactor according to the invention is useful as a treatment device for hydrogen chloride. Therefore, the processing apparatus for dehydrochlorination treatment or the like according to the present invention is used for applying dehydrochlorination or the like to chlorine-containing plastics and the like contained in waste plastics prior to decomposing and oiling waste plastics or incineration. Therefore, it has a mortar-shaped heating surface that is inclined downward toward the communication hole provided in the center portion, and is heated while allowing waste plastic to flow down along the heating surface, so that the dehydrochloride or the like is heated. A reaction section which causes a reaction to be a pre-processed product, a stirring means for stirring waste plastic on a heating surface of the reaction section, and a preparatory means which is connected to the reaction section via the communication hole and flows down the heating surface. It is provided with a sending section for sending the processed material to a device for cracking and oiling treatment or incineration treatment.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A processing apparatus according to a first embodiment of the present invention includes a pre-reactor 1 and a main reactor 2 as shown in FIG. The pre-reactor 1 has a structure in which the inner frame 3 having a funnel shape as a whole and having a sealed structure is covered with an outer frame 4 having a similar heat insulating structure to form a hot air passage 5 therebetween. And The inner frame 3 is provided with a supply port 6 for supplying waste plastic to a reaction section described later and a discharge port 7 for extracting gas from the reaction section, and the outer frame 4 is shown in the hot air passage 5. Burner connection ports 8 and 8 for feeding high-temperature hot air with a non-burner and an exhaust port 9 for discharging the hot air are provided.

The mortar-shaped upper part of the inner frame 3 forms a reaction part 11, and the cylindrical lower part forms a transfer part 12. These reaction unit 11 and transfer unit 1
2 is connected via a communication hole 13 at the lower end of the reaction section 11. The reaction section 11 uses a mortar-shaped slope having a downward slope toward the communication hole 13 as a heating surface 14, and the heating surface 14 receives heating energy from the hot air passage 5. Further, the reaction section 11 is provided with a stirring blade 1 that operates to sweep the heating surface 14.
5a and 15b are provided as stirring means. This stirring blade 15
a and 15b connect the inner frame 3 to a rotating shaft 16 provided so as to vertically penetrate the center of the inner frame 3, and perform the above operation in response to the rotation of the rotating shaft 16 by the motor 17.

The transfer section 12 is provided with a screw conveyor 18 as transfer means. The screw conveyor 18 is formed by connecting a screw blade 19 to the rotating shaft 16. The transfer section 12 is provided with a delivery section 20 at the lower end thereof.

Although various types can be used as the main reactor 2, an oiling reactor as shown in FIG. 2 is preferably used. This oiling reactor has a structure in which an outer cylinder 22 and an inner cylinder 23 are combined so as to form a reaction chamber 24 therebetween. The inner cylinder 23 has a conveying blade 25 on its outer periphery and gears 26, 26.
It is configured to be rotated by a drive source 27 via 6, 6. The inside of the inner cylinder 23 forms a hot air passage 28, and heats the reaction chamber 24 from the inside by high-temperature hot air blown by a burner 29. Then, the reaction chamber 24 is connected from the pre-reactor 1 through the receiving port 30 connected to the delivery section 20.
Is transported continuously in the direction of the arrow X in the reaction chamber 24 by the rotation of the inner cylinder 23, and is heated and decomposed and vaporized during the transport, and the vaporized substance is discharged from the vaporized material outlet. It is sent out from 31 and is cooled by a collecting device (not shown) and collected as oil.

An example in which a mixed waste plastic containing polyvinyl chloride is treated using such a continuous treatment apparatus will be described below. The solid waste plastic, which has been cut or reduced in advance, is supplied with a metal for chloride formation, for example, aluminum chips, and the like at a constant amount by a predetermined amount.
Supplied from The waste plastic supplied in this manner is spread over the entire heating surface 14 by being made into a thin layer by the stirring blades 15a and 15b, and accordingly, aluminum chips are uniformly dispersed in the waste plastic. I do. Then, by being heated to 250 to 350 ° C. by the heating surface 14, polyvinyl chloride in the waste plastic causes a dehydrochlorination reaction, and reacts with the generated hydrogen chloride to convert aluminum into aluminum chloride. Excess hydrogen chloride gas is extracted from the extraction port 7 to a recovery device (not shown).

Through such a reaction, the solid waste plastic gradually softens and becomes a pretreated material having fluidity. The pre-processed material slowly flows down along the heating surface 14 and enters the transfer unit 12 through the communication hole 13. The pre-processed material that has entered the transfer unit 12 is sent downward by the screw conveyor 18 over a certain period of time. During this time, the chlorine remaining in the pre-processed product reacts with aluminum to further promote the production of aluminum chloride, and at the same time, the generated aluminum chloride is uniformly dispersed in the pre-processed product. During this time,
By further heating, non-liquefied components are removed to liquefy and produce a liquid phase polymer. The pretreated material sent downward in this manner is sent out from the sending section 20 to the main reactor 2. The oiling treatment in the main reactor 2 is performed as described above, and at this time, the above-mentioned aluminum chloride acts as a catalyst for oily cracking, so that the cracking can proceed efficiently.

As shown in FIG. 3, the prereactor in the processing apparatus according to the second embodiment of the present invention has a transfer section 41 provided with a non-liquefied component recovery section 42 at the lower end thereof. The non-liquefied component recovery unit 42 is for recovering non-liquefied components contained in the pre-processed product as pellet-like solids, and includes a pumping unit 43 and a storage unit 44.

The pressure feeding section 43 is formed by reducing the diameter of the lower end of the transfer section 41, and is used for feeding a non-liquefied component at a large pressure by a high-pressure screw conveyor 18s provided integrally with the screw conveyor 18. Function. The non-liquefied component S that is pumped by receiving the strong pumping force of the pumping unit 43 is stored in the storage unit 44 by being pelletized or the like. On the other hand, the liquid-phase polymer L generated as described above from the pre-processed material stays in the clean water state on the non-liquefied component S that is densely packed in the pumping unit 43, and is discharged from the main reactor through the sending unit 46. Leaked to

[0021]

As described above, according to the present invention, the preliminary treatment prior to the oiling treatment can be efficiently performed,
It is possible to improve the efficiency of liquefaction treatment of mixed waste plastics containing polyvinyl chloride or the like.

[Brief description of the drawings]

FIG. 1 is a simplified cross-sectional view showing a prereactor which is a main part of a processing apparatus according to a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional side view schematically showing a main reactor in the processing apparatus according to the first embodiment of the present invention.

FIG. 3 is a sectional view schematically showing a main part of a pre-reactor in a processing apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Preliminary reactor 2 Main reactor 11 Reaction part 12, 41 Transfer part 13 Communication hole 14 Heating surface 15a, 15b Stirring blade (stirring means) 18 Screw conveyor (transfer means) 20,46 Delivery part 42 Non-liquefied component recovery part

Claims (3)

[Claims] 1. A pre-reactor and a main reactor are provided, and after a pre-treatment such as dehydrochlorination is performed in the pre-reactor, an oiling treatment or the like is continuously performed in the main reactor. A waste plastic treatment apparatus, wherein the preliminary reactor has a mortar-shaped heating surface that is inclined downward toward a communication hole provided in a central portion, and the waste plastic flows down along the heating surface. A reaction section which causes a reaction such as the above-mentioned dehydrochlorination by heating while making it a pre-processed product,
Stirring means for stirring the waste plastic on the heating surface of the reaction section, transfer which is connected to the reaction section via the communication hole, receives the pretreated material flowing down the heating surface, and transfers it by the built-in transfer means. A processing apparatus, comprising: a feeding section for feeding a pre-processed material from a transfer section and a feeding section for feeding the pre-processed product to the main reactor. 2. The processing apparatus according to claim 1, wherein the transfer unit includes a non-liquefied component recovery unit for separating and collecting the non-liquefied component from the pre-processed material. 3. A treatment apparatus for subjecting chlorine-containing plastics and the like contained in the waste plastics to dehydrochlorination or the like prior to the decomposition and oiling treatment or the incineration treatment of the waste plastics, which is provided in a central part. It has a mortar-shaped heating surface that is inclined downward toward the hole, and a reaction such as the above-mentioned dehydrochlorination is caused by heating while causing waste plastic to flow down along the heating surface to produce a pre-processed product. , A stirring means for stirring the waste plastic on the heating surface of the reaction section, connected to the reaction section via the communication hole, and the pretreated material flowing down the heating surface is subjected to decomposition oiling treatment or incineration treatment. A processing unit comprising a sending unit for sending out to a device for processing.