JPH01148517A - Method for disposing used plastic bottle - Google Patents

Abstract

PURPOSE:To contrive to improve the sorting work and crushing efficiency by a method wherein a plurality of plastic materials, which are made separable by thermally shrinking used plastic bottles, are sorted in response to their qualities of material and finally sorted plastic materials are respectively crushed. CONSTITUTION:Plastic bottles are sent with a feeding conveyer 1 to a heating device 2 so as to be thermally shrunk by being sprayed with heated water during their transport under rotation. At this time, the fitting state of a stand to a PET bottle main body is disengaged by the difference between their thermal shrinkage factors due to the difference between their qualities of material. Further, metal caps easily come out. Furthermore, the plastic bottles go to small pieces through thermal shrinkage. After that, transparent bottles, green bottles and stands are sorted manually and sent through a large number of chutes 4, which are arranged at both sides of a sorting conveyer 3, onto respective conveyers 5a-5c so as to be ground to the predetermined sizes with grinders 6a-6c in order to be sent to filling machines 15a-15c for sacking by means of air chutes 7a-7c.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a processing method for processing used plastic bottles into recycled plastic materials.
In particular, it is suitable for processing plastic bottles that have a reinforcing member called a hook on the bottom.

(Prior Art) In recent years, one-way plastic bottles have been widely used as containers for soft drinks and alcoholic beverages in place of conventional glass bottles.

In particular, conventional plastic bottles were relatively small, but recently plastic bottles have become larger, such as 1 to 1.5 square meters, and bottles that need to withstand high internal pressure, such as carbonated drinks, and even larger bottles. are colored to protect the contents, etc.
Their types are also diversifying.

Such plastic bottles are discarded after use, but from the perspective of effective resource utilization, attempts are being made to crush and refine them and recycle them as plastic raw materials.

As such a used plastic bottle processing apparatus, Japanese Utility Model Publication No. 61-38672 (name: waste bottle processing apparatus) has been known.

This device uses a pulverizer to crush used plastic bottles, and then uses dry and wet separators to separate them from foreign substances such as paper and aluminum attached to the used bottles.

(Problem to be solved by the invention) However, in the above-mentioned conventional technology, used plastic bottles are directly fed into a crusher, and as plastic bottles have diversified in recent years, their constituent materials have become increasingly diverse. If different types of plastics are simply put into a crusher, they will be mixed together and it will be difficult to sort them out, which has the major drawback that the recycled plastic raw materials will be of low quality with lots of impurities. Ta.

In particular, bottles made of polyethylene terephthalate, commonly called PET bottles, are available in transparent versions and those with a coloring agent called green to protect the contents.
Since a black protective member made of high-density polyethylene called a hakama is also crushed, if these were put into a crusher and crushed, it would be impossible to separate each material afterward.

However, it is not possible to manually remove the metal caps that are screwed into the mouth of the pot or bottle before loading the crusher, since the pot itself is fitted into the PET bottle and cannot be easily removed. The cap was screwed in, so you had to turn it to remove it, which was a hassle.

Moreover, since used bottles are empty and bulky, only a small number of bottles must be fed into the crusher at a time, resulting in poor crushing efficiency.

The present invention solves the problems of the prior art as described above, and provides a method for processing used plastic bottles in which each plastic material can be easily sorted prior to pulverization, and the pulverization efficiency of the pulverizer is excellent. purpose.

[Structure of the Invention] (Means for Solving the Problems) The method for processing used plastic bottles of the present invention heat-shrinks a used plastic bottle made of a plurality of plastic materials, and separates each plastic material separately. The present invention is characterized in that a plurality of separable plastic materials are sorted according to their materials, and each of the sorted plastic materials is pulverized.

(Function) In the present invention having the above-mentioned configuration, the plastic bottle is heated and shrunk by the heating device before sorting the plastic materials, so that the PET bottle body and the hook that are fitted together can be easily separated. The cap screwed into the mouth can also be easily removed.

Furthermore, as the overall volume is reduced through heat shrinkage, it becomes possible to feed large quantities of plastic bottles into the crusher.
Grinding efficiency is also improved.

(Example) Hereinafter, an example of the present invention will be specifically described based on the plan view of FIG. 1 and the side view of FIG. 2.

(2) Supply process In the present invention, plastic bottles to be treated are fed to a heating device 2 by a supply conveyor 1.

(2) Heating shrinkage process The heating device 2 has a configuration shown in FIGS. 3 and 4, for example.

That is, on the support roller 22 provided on the frame 21,
A horizontal perforated drum 20 is rotatably provided by a motor 23 also provided on a frame 21.

The perforated drum 20 is made of punched metal, wire mesh, or the like so that the heated water sprinkled inside the drum is discharged from the bottom of the drum.

A spiral feeding blade 24 is provided on the inner surface of the perforated drum 20 to transport a plastic bottle placed inside. Further, between the feeding blades 24, a plurality of bolts 25 for stirring the plastic bottle inside the perforated drum 20 are protruded at predetermined intervals.

The supply conveyor 1 is located at the entrance of the perforated drum 20.
A charging chute 2G for charging plastic bottles into the perforated drum 20 from the end of the perforated drum 20 is provided. A sorting conveyor 3 is arranged to transport the shrunken plastic bottles to be discharged.

A support member 27 extending in the direction of the rotational axis of the drum is provided at the center of the drilling tram 20, and a heated water dispersion device 30 is provided on the support side 27. This spraying device 30 is connected to a recovery tank 33 disposed below the perforated drum 20 via a water supply pipe 31 and a pump 32. A water supply pipe 34 of heated water heated to a high temperature and a drain pipe 35 are connected to the recovery tank 33 . As an example, the recovery tank 33 is divided into five sections along the axial direction of the perforated drum, and the central three sections are heated.
Others are heated by residual heat.

This heating device is equipped with the above-mentioned perforating drum 20 for transporting plastic bottles while rotating, and a spraying device 30 for spraying heated water onto the drum. It is heated and shrunk when it comes into contact with water. At this time, due to the difference in heat shrinkage rate between the PET bottle body and the hook due to the difference in materials, the fitting state of the two may come off or come off easily. Also, since the metal cap that is screwed onto the mouth does not shrink, the mouth of the bottle contracts inside the cap, making it easier to remove the cap from the mouth. Further, due to heat shrinkage, the plastic bottles 1 to 1 are crushed and their bulk becomes smaller. Sprinkling heated water will also remove dirt and foreign matter from the surface of the plastic bottle.
Labels, etc. will be removed.

■Sorting process Heat-shrinked plastic bottles are processed using a perforation drum 20.
and is sent to the sorting conveyor 3 installed at the subsequent stage. On both sides of the sorting conveyor 3, there are a large number of shoes
The input ports of the shoes 1 to 4 are open, and these shoes 1 to 4 are connected to the transparent small bowl conveyor 5a, the green bowl conveyor 5b, and the hook conveyor 5C provided at the lower stage of the sorting conveyor 3, respectively. There is. Therefore, the plastic bottles sent to the sorting conveyor 3 are manually sorted into transparent bottles, green bottles, and pots, and then sent through chutes onto the respective conveyors 5a to 5C.

(1) Grinding process At the end of each of the conveyors 5a to 5C, grinders 68 to 6C are provided, and each material sent there is ground to a predetermined size (for example, about 1.Q mm square).

Air chutes 7a to 7G are connected to the outlet portions of the crushers 6a to 6G, respectively, and among these air chutes 1 to 7G for pots are directly connected to a filling machine 15G for bagging.

φ ■ Defibration process transparent bottle 1 ~ air chute 5a for green small bottle,
5b is connected to disintegrators 8a and 8b.

That is, since the crushed products of transparent bottles and green bottles have labels or other foreign matter attached to them that could not be removed in the sorting process, these foreign matters are removed by rubbing them with a disintegrator.

The disintegration 18a, 8b consists of, for example, a screw conveyor having a structure as shown in FIG. It is stirred by arm 82. In addition, the casing 80 is provided with a water supply port 83 and a drain port 84 to facilitate the removal of foreign matter, and also to remove plastic waste that should sink due to air bubbles adhering to the surface of the crushed material during specific gravity separation in the next process. prevent it from floating.

■Floating separation process At the latter stage of the disintegrators 3a and 3b are specific gravity separators 9a and 9.
b is provided. This specific gravity separation device is also used in the prior art described above, but while PFT bottles sink in water with a specific gravity of less than 1, labels made of polyethylene film and containers made of high-density polyethylene have a specific gravity of less than 0.
Since it sinks in water with a value of about 95 to 0.97, the two are poured into a water tank and separated by floating.

■Washing and dehydration process A washing and dehydration device 10 is installed after the specific gravity separation devices 9a and 9b.
A and 10b are provided, and this washing and dehydrating device washes foreign matter such as label valves remaining in the crushed Plus Deck and dehydrates it. These washing and dehydrating devices 1e
a, 10b are connected to filling machines 15a, 15b by air chutes 11a, 11b, and the washed and dehydrated plastics are sent to these filling machines 15a, 15b and packed into bags.

(Other Examples) The present invention is not limited to the above-mentioned examples, but also includes other examples such as those described below.

■Use a heat-shrinking device that immerses used plastic bottles in heated water.

■As a heating device, use a device that passes a conveyor that transports plastic bottles through a warm air tunnel.

■ Even if it is attached to a pot, it can be passed through a disintegrator, gravity separator, and washing-drying machine, just like transparent bottles and green bottles.

■After cleaning and dehydration, the crushed plastic is further processed into pellets.

■More or fewer than the number of plastic materials to be sorted.

[Effects of the Invention] As described above, according to the present invention, when recycling a used plastic bottle made of a plurality of PlusDeck materials, the entire bottle is heated and shrunk before being sorted by its constituent materials. This makes it possible to easily separate and classify the constituent materials that fit into each other, and the efficiency of the sorting work is greatly improved. Furthermore, since the volume of the bottle is reduced by heat shrinkage, there is also the advantage that crushing efficiency is improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the processing method of the present invention, FIG. 2 is a side view of the same, FIG. 3 is a sectional view showing an embodiment of the heat shrinking apparatus used in the present invention, and FIG. 4 5 is a front view of the same as above, and FIG. 5 is a sectional view showing one embodiment of the disintegrating machine used in the present invention. DESCRIPTION OF SYMBOLS 1... Supply conveyor, 2... Heating device, 3... Sorting conveyor, 4... Chute, 5a-5G... Conveyor, 68-6C... Crushing machine, 7a-7G... Air chute, 3a, 8b...disintegrator, 9a, 9b...
Specific gravity separator, 10a, 10c... washing and dehydrating device, 11
a, 11b...air chute, 158~15G...
Filling machine, 20... Perforated drum, 30... Spraying device, 33... Recovery tank.

Claims (1)

[Claims] (1) Used plastic bottles made of multiple plastic materials are heated and shrunk to make them separable into individual plastic materials, and these separable plastic materials are sorted and sorted according to their materials. A method for processing used plastic bottles, which comprises pulverizing each plastic material.