JPH09277258A - Plant for converting waste plastic to resources - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily collect treated waste plastic in the future to again utilize the same as resources by compressing, crushing and drying waste plastic from which impurities such as a metal and the like are removed to fuse the same under heating and cutting the fused waste plastic to adjust the shape thereof to bag and pack the waste plastic before storing the same. SOLUTION: In a plant, the waste plastic received in the plant is cut and unpacked to be flatly leveled and iron refuse is magnetically separated and metal/earth and rocks other than iron are subsequently separated in a first separation tank. Continuously, the waste plastic is compressed to separate hollow containers made of a metal such as A in a second separation tank. After the above mentioned impurities are separated, the waste plastic is crushed to be supplied to a vibration screen to be arranged in its size and shape. The waste plastic passed through the vibration screen is supplied to a next moisture separating/drying process. The dried and crushed waste plastic pieces are once stored and subsequently passed through respective processes of heating, quantitative cutting, molding and washing/cooling to be converted to resources. The plastic converted to resources is stored and successively bagged and packed to be fed out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste plastic resource recycling plant (hereinafter referred to as a plant), more specifically, waste plastics (hereinafter referred to as waste plastics) that are household wastes, which are separately collected. To burn
Without discarding as it is, impurities such as metals are separated and removed, compression crushed and dried, heat fusion is performed, cutting is performed, the shape is adjusted, and the product is packaged in a bag, and stored together.
The present invention relates to a plant for recycling waste plastic so that it can be easily collected and reused as a resource in the future when resources will be exhausted.

[0002]

2. Description of the Related Art Today, with the development of the petrochemical industry, plastic products are abundant in daily life and provide great convenience to our daily lives. Plastic products that have once fulfilled their purpose of use are discharged in large quantities as domestic waste, and the treatment thereof has become an issue today.

Generally, a plastic is obtained by polymerizing petroleum naphtha as a starting material, or a low molecular weight polymer 6 thereof.
Since it is a high molecular compound that is copolymerized with 0 to 70% of other compounds and 40 to 30% of other compounds, recycling of the waste plastic that has been separated and recovered is depolymerized and returned to the original petroleum naphtha for reuse as a raw material. There are two possible methods: recycling or recycling as plastic. Regarding recycling, this method is used for recycling metals having a single composition, and iron is iron, copper is copper, and aluminum (hereinafter referred to as Al) even if manufacturing makers are different. Al
It is used as a reproduction. On the other hand, the recycling of plastics is almost impossible with the exception of a very few cases where polyethylene of the same manufacturer is recycled into food bags and sheets. This is because, even with the same plastic, the manufacturing method, molecular weight, composition, etc. differ depending on the manufacturer.

On the other hand, if a method of decomposing the waste plastics separated and recovered into the original petroleum naphtha and other compounds is selected, a plant as large as that for polymerizing the plastics using petroleum naphtha as a starting material is required. To do. But,
At present, it is much cheaper to polymerize plastics using petroleum naphtha as a starting material than to recycle waste plastics, so a large investment is made to construct a plant for disassembling waste plastics. I can't think of that.

However, the petroleum reserves of fossil fuels are finite and may be depleted, so that the supply thereof is not guaranteed forever. Since it is not economically feasible at present, it is fully expected that waste plastic that will not be reused as a raw material for plastic polymerization will be focused on as a resource in the future, and the road to its utilization will be opened.

Currently, the plastic usage fee in Japan is about 1 kg per person per month, and about 70% of it is for household use. About 70% of this 500gr is recovered, and in addition to being reused in food bags and sheets, most of the rest is incinerated along with garbage, and part of it is in the state of being recovered. It may be discarded as it is or used for landfill. Not only is it bulky to dispose of as it is, or to be used for landfill, but since plastic has high corrosion resistance, it remains semi-permanently without decomposition. Although it may be bulky or remain for landfill use, it is environmentally problematic if it is left on the ground without being decomposed semipermanently.

Further, in the case of incineration, a large amount of carbon dioxide gas is generated, and the carbon dioxide content% of the atmosphere is increased, which causes the global warming phenomenon. As mentioned above, the amount of plastics collected per capita in Japan is about 0.5 kg per month, and the population of 120 million people is about 72 per year.
It becomes 50,000t. It is nothing more than a waste of resources to smoke or throw away most of this large amount of collected waste plastic. The "Containers and Packaging Recycling Law" came into effect in April 1997, and is planned to be applied to plastics after the grace period of 3 years has passed. Recycling of plastics is a pressing issue.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and its purpose is to prepare for when fossil fuel oil reserves are exhausted and supply thereof becomes difficult. Since it is not economically feasible right now, by providing a plant that recycles waste plastic that is not reused so that it can be used as a resource in the future, it can be discarded or landfilled as it has been in the conventional manner. The purpose is to avoid waste of resources and environmental problems by replacing the waste plastics used for industrial purposes or by burning treatment.

[0009]

[Means for Solving the Problems] And, the purpose is to receive waste plastics, cut and unpack, iron scrap magnetic separation process, non-ferrous metal / debris separation process, compression process, non-ferrous metal hollow container separation process such as Al, crushing. Process, vibration sieving sorting process, water separation
Achieved by a waste plastic recycling plant that has a drying process, a waste plastic dry crushed piece storage tank, a continuous heating extrusion process, a quantitative cutting process, a molding process, a washing and cooling process, a recycled plastic storage tank, and a bag packing process. it can.

[0010]

With the above construction, in the invention of claim 1, the waste plastics separated and collected are received by the plant, cut and unpacked, and are flattened uniformly on the conveyor. Are magnetically selected and removed. Next, metals other than iron and debris are separated and removed in the water tank due to the difference in specific gravity. The waste plastic from which iron, metals other than iron, and debris has been separated and removed is crushed through a compression process and the hollow container made of non-ferrous metal such as Al is crushed and dropped into the second water tank. Separated and removed. Then 1
It is carried to the next crusher, crushed and washed, and then dropped into the third separation tank, and the hot plastic water is drained from the waste plastic crushed pieces.
The waste plastic crushed pieces from which the hot water has been drained are screened by a vibration sieving and sorting machine and sent to the next water separation / drying step. It should be noted that the large-sized one that does not pass through the sieve is further crushed and washed by the secondary crusher, and then subjected to the vibrating screen sorter until it passes the screen. In the next water separation / drying process, hot air is blown to the waste plastic crushed pieces that have passed through the sieve in the rotary perforated drum conveyor to evaporate the water to be blown off, dried in a dryer and temporarily stored in a storage tank. To do. The waste plastic dry crushed pieces temporarily stored are sent to a continuous heating / pressurizing extruder by an air conveyor, where they are pressure-fused and integrated to quantitatively cut them, put them in a mold, and save the resources. Mold it so that it is convenient to use. The recycled waste plastic thus molded is finally washed and cooled in a water tank, passed through a recycled waste plastic storage tank, packed in a bag, and carried out.

If the discharged waste plastics are stored together by dividing one corner of the garbage disposal site, they can be easily collected and reused as plastics or other raw materials when a need arises in the future. it can.

[0012]

Next, an embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited to these examples.

FIG. 1 is a process diagram of the plant 1 of the present invention. The plant 1 is not designed to treat food waste, so it receives the separated waste plastic, cuts and unpacks it to flatten it, separates the iron scraps by magnetic separation, and then the first separation. Separate metal and debris other than iron in a tank. Subsequently, in the compression step, the hollow container made of non-ferrous metal such as Al is separated in the second separation tank. When the above contaminants are separated, they are crushed in a crushing step, and sieved in a vibrating sieving and sorting step so as to have a predetermined size. Those that do not pass the sieving are crushed again in the secondary crushing step, returned to the vibrating sieving and sorting step, sieved, and repeated until they pass. Those that have passed the vibrating and sieving process are sent to the next water separation and drying process. The dried crushed pieces of waste plastic that have undergone the water separation / drying step are temporarily stored and then recycled as resources through a continuous heating extrusion step, a quantitative cutting step, a molding step, and a washing / cooling step. The recycled plastics are stored and sequentially carried out through a bag packing process.

The upper part of FIG. 2 shows the steps of receiving, cutting, unpacking and magnetic separation of the waste plastic of the plant 1. Waste plastics such as empty cans and PET bottles that have been separated and collected are carried in by trucks, excavators, etc., and then reciprocating conveyors.
It is thrown into No. 2 and is sent out to the vibrating type conveyor-3 by a fixed amount. The waste plastic is spread evenly on the vibratory conveyor-3, and the waste plastic packed in the bag is cut and unpacked by the roller 4 installed on the conveyor-3, and the next conveyor belt conveyor-5 is installed. Sent to.
A person is assigned to this belt conveyor 5 to manually remove paper scraps and wood chips that cannot be removed by the plant 1. In the magnetic separator 6, an electromagnet is incorporated in a belt conveyor that rotates around it, and the electromagnet works on the conveyor belt conveyor 5 to adsorb and pick up iron scraps in the waste plastic, and the conveyor belt 7 is conveyed to the conveyor belt 7. Then, the electricity is cut off and the absorbed iron scraps are released. The scrap iron scraps are conveyed to the end of the conveyor belt conveyor-7 and fall,
It is removed from the system as stored iron scrap 8. The waste plastic from which the iron scraps have been removed is conveyed to the end of the conveyor belt conveyor-5, falls from the gap formed between the conveyor belt conveyor-5, and is sent to the next metal / debris separation process other than iron. .

An arrow A shows the flow to the metal / debris separation process other than iron at the center of the middle stage of FIG. 2 and the compression process at the right end thereof. The waste plastic from which the iron scraps have been removed falls from the end of the conveyor belt conveyor 5 into the first separation tank 9. The first separation tank 9 is filled with water, and metals other than iron, which has a heavy specific gravity, and debris sink, and light waste plastics and the like float up. Metals and debris other than sinking iron are ladder type conveyor-10
Are transported to the end of the conveyor belt conveyor 11 and released outside the system as metals and debris 12 other than the stored iron. The light waste plastics and the like that have floated in the first separation tank 9 are captured by the stitch type discharge conveyor-13, conveyed to the conveyor belt conveyor-14, and dropped from the end of the conveyor-14 to the hopper of the roller15, It is compressed by the roller 15 and falls into the second separation tank 16.

The lower part of FIG. 2 shows the steps from the second separation step to the non-ferrous metal hollow container separation step such as Al to the drying step.
The second separation tank 16 is filled with water, and the light waste plastic floats, but the compressed and crushed container made of non-ferrous metal such as Al sinks. This is because the hollow container has a low specific gravity, but the volume is reduced by being compressed by the roller 15 and the original specific gravity of the metal is restored. The container made of non-ferrous metal such as compressed Al that has settled on the bottom of the second separation tank 16 is scooped up by a ladder type conveyor 17 and is conveyed and discharged by a conveyor belt conveyor 18 to be stored outside the system as non-ferrous metal 19 such as Al. To be removed. The waste plastic floating on the water surface of the second separation tank 16 is scooped up by the mesh belt conveyor 20 to convey the conveyor belt.
21 and the primary crusher 2 at the end of the conveyor -21
Fall to 2.

The primary crusher 22 is a shredder type, and crushes the waste plastic that has dropped while receiving hot water from the hot water supply device 23. To prevent the waste plastic from burning on the cutting teeth of the shredder due to the frictional heat generated during crushing, and to clean the contents of the hollow container, 40 ~
Hot water of 60 ℃ is supplied. The crushed pieces of waste plastic fall into the saucer tank of the third separating tank 24 below. A mesh belt conveyor 26 is laid along the bottom and the inclined side wall of the tank 24, receives the falling waste plastic crushed pieces here, and drains the water for hot water supply while cutting the water for hot water supply and along the inclined side wall of the third separation tank 24. It is pulled up and transferred to the conveyor belt conveyor 26. A drain port (not shown) is provided at the bottom of the third separation tank 24, and water is drained to the outside of the system from here.

The waste plastic crushed pieces transferred to the conveyor belt conveyor-26 are vibrated and sieved from the end thereof by the vibrating screen sorter 2.
Fall to 7. The waste plastic crushed pieces are then sized to a certain shape. In other words, the oversize that does not pass through this sieve is the conveyor belt conveyor-2.
8 is also carried to the shredder type secondary crusher 29, where it is crushed again while receiving hot water from the hot water supply device 30, dropped into the fourth separation tank 31, and a mesh belt conveyor laid at the bottom thereof. It is pulled up while draining the hot water at 32, and the conveyor belt conveyor 33 conveys the conveyor belt conveyor 26 in the previous step of the vibrating and screening machine 27.
To be returned as indicated by arrow B. Here, it joins the main stream from the third separation tank 24 and is sieved again. If it still does not pass, it is crushed again, and finally passes and proceeds to the next step.

The waste plastic crushed pieces that have passed through the vibrating screen sorter 27 are dropped onto the under-sieving draw-out conveyor 34, drawn out, transferred to the conveyor belt conveyor 35, and mounted on the conveyor belt conveyor 35 to rotate. It is conveyed to the perforated drum conveyor-36. In the rotary perforated drum conveyor 36, hot air is blown from the warm air blower 37 in the direction opposite to the rotating direction, and the waste plastic crushed pieces are drained and roughly dried. The waste plastic crushed pieces that have passed through the rotary perforated drum conveyor-36 and have been drained and roughly dried are carried by the conveyor belt conveyor-38 to the multi-stage dryer 39, and from the multi-stage dryer 39 to the storage tank 40. Is conveyed as indicated by arrow C.

FIG. 3 is an explanatory view of the final process of the plant 1 from the temporary storage after the drying process to the bag packing process. After being dried by the multi-stage dryer 39, it is temporarily stored in the storage tank 40. Fine particles of the waste plastic crushed pieces in a dry state may be suspended in the air or stacked to generate high-voltage static electricity, which may cause a lightning accident or an ignition accident. Grounding of the tank 40 should be sufficient.

The waste plastic crushed pieces stored in the storage tank 40 are taken out by the air conveyor 41, fed into the hopper of the continuous heating / pressurizing extruder 42, and heated in the main heating / pressurizing extruder 42. Fused, continuously extruded by pressure, and recycled. The waste plastic that has been recycled into resources is cut into a fixed amount by the fixed amount cutting device 43,
It is molded into a regular shape by the molding device 44 in consideration of convenience of handling. The formed waste plastic is washed and cooled in the washing cooling water tank 45, pulled up by the ladder type conveyor 46 laid along the bottom and the inclined side wall of the water tank 45, transferred to the conveyor belt conveyor 47, and shipped or shipped. It is temporarily stored in the storage tank 48 until bagged packaging. The recyclable waste plastic temporarily stored in the storage tank 48 is pulled out by the pull-out conveyor 49, and then the bag packing apparatus 50.
They are packed in bags and shipped in bulk. In addition,
In order to take out the waste plastic crushed pieces from the storage tank 40 described above, it is possible to use a screw conveyor instead of the air conveyor 41.

[0022]

As described above, according to the plant 1 of the present invention, in preparation for the depletion of fossil fuel oil reserves,
Waste plastic that is not reused now due to economic unprofitability is provided as a resource recovery plant to be used as a resource in the future. Alternatively, waste of resources and environmental problems can be avoided as an alternative to waste by incineration.

[Brief description of drawings]

FIG. 1 is a process diagram of a plant 1.

FIG. 2 is an explanatory diagram of a first half process of the plant 1 from a process of receiving, cutting, unpacking, magnetic separation of waste plastic to a drying process.

FIG. 3 is an explanatory diagram of a final process of the plant 1 from storage after the drying process to bagging and packaging process.

[Explanation of symbols]

1 Plant 2 Reciprocating Type Conveyor 3 Vibration Type Conveyor 4 Cutting Unpacking Roller 5, 7, 11, 14, 18, 21, 26, 28, 33,
35, 38, 47 Conveyor Belt Conveyor 6 Magnetic Separator 8 Storage Iron Scrap 9 First Separation Tank 10, 17, 46 Ladder Type Discharge Conveyor 12 Stored Metals and Debris Other Than Iron 13, 20, 25, 32 Mesh belt conveyor -15 Compression roller 16 Second separation tank 19 Non-ferrous metal such as stored aluminum 22 Primary crusher 23, 30 Hot water supply device 24 Third separation tank 27 Vibrating screen sorter 29 Secondary crusher 31 Fourth separation tank 34 Under-sieve drawing conveyor-36 Rotary perforated drum conveyor-37 Warm air blower 39 Dryer 40, 48 Storage tank 41 Air conveyor-42 Continuous heating / pressurizing extruder 43 Quantitative cutting device 44 Molding device 45 Washing cooling water tank 49 Drawer Conveyor-50 Bagging and Packing Equipment

Claims (1)

[Claims] 1. A waste plastic receiving / cutting / unpacking / iron scrap magnetic separation process, a metal / debris separation process other than iron, a compression process, a non-ferrous metal hollow container separation process such as aluminum, a crushing process,
Vibrating and sieving process, water separation / drying process, waste plastic dry crushed piece storage tank, continuous heating extrusion process, quantitative cutting process, molding process, washing and cooling process, recycling waste plastic storage tank, and bag packing process Waste plastic recycling plant characterized by.