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2025 edition
March, 2025 issue Let's reduce plastic waste by recycling!　-Environmentally friendly behavior from Yokohama~

The text is from here.

March, 2025 issue Let's reduce plastic waste by recycling!　-Environmentally friendly behavior from Yokohama~

Last updated on March 1, 2025.

　From April, plastic disposal procedures will change in all 18 wards. In addition to conventional plastic containers and packaging, products made of plastic alone will be collected and recycled as plastic resources.
　This time, we covered the flow until the collected plastic waste was reborn as "plastic resources". Here are some points that we can work on in our daily lives!
In addition, in public information Yokohama March issue (outside site), we introduce plastic disposal procedures.

Why do we have to reduce plastic waste?

　Plastics are lightweight, durable, and easy to process, so they are widely used in daily necessities and containers and packaging. Super shopping bags, food trays, detergent containers, egg packs, etc. There are no days we can't see in our lives.
　It is such a convenient plastic, but when burned, it generates a large amount of greenhouse gases such as carbon dioxide. If greenhouse gases increase too much, the earth will gradually be warmed up. This is the so-called "global warming." As global warming progresses, extreme weather events such as intense heat, droughts and torrential rainfalls will increase, making it difficult for many animals and plants, including humans, to live.

Image provided: PIXTA (Pixta)

Image provided: Kanagawa Coastal Beautification Foundation

　So if you don't burn it, that's not the case. Littered or illegally dumped plastic garbage is not naturally decomposed and remains in the sea, rivers, and mountains. It will not disappear at all. Animals and fish can eat plastic waste, which has a significant impact on ecosystems.
　It is now very important to reduce the amount of plastic waste produced by humans with human hands.

How do I reduce plastic waste?

　The city of Yokohama contains approximately 140,000 tons of plastic waste annually in burnable garbage (FY2023 results). However, if all of them are divided into "garbage" and "recyclable materials (recyclable materials)" instead of using them as garbage, recyclables can be reborn as new ones.
　To this end, burnable garbage collects plastic-only products, together with plastic containers and packaging, as plastic resources, and recycles them.
We will reduce the amount of burnable plastic waste by recycling more plastic waste with the cooperation of citizens.

Until plastic resources are recycled

　Plastic resources will be transformed into new products through processes at two plants, an intermediate treatment facility and a recycling facility. At the intermediate treatment facility, separation and compression packing work are performed to remove foreign substances that have been mixed into plastic resources. The compressed and packed plastic resources are processed into recycled products and chemical raw materials at the recycling facility.　
　There are two types of recycling: "material recycling," which is reborn as plastic containers, food trays, and clothing, and "chemical recycling," which is pyrolysis at high temperatures and used as a chemical raw material.
　This time, we observed the recycling process of Kaneko Co., Ltd., an intermediate treatment facility, and Resonak Co., Ltd., which is engaged in chemical recycling.

[Kaneko Yokohama Tozuka Plant]　

Plastic resources collected by garbage trucks

Garbage trucks collected in Konan Ward, Totsuka Ward and Sakae Ward come one after another, and plastic resources from households are collected in one place.

The plastic resources collected at the intermediate treatment facility are broken by a machine, the contents are removed, placed on a belt conveyor, and transported to the next sorting area.

"Lithium bather" sorts lithium-ion batteries and foreign substances made of metal mixed in plastic resources. When lithium-ion batteries or metal garbage pass through, the lamp lights up red at the same time as the alarm sound, notifying foreign matter contamination.

We quickly and accurately sort plastic resources and remove foreign substances.

Foreign substances mixed in plastic resources are removed manually by employees. Other resources, such as plastic bottles and paper packs, which cannot be detected by lithium busters, are also removed by employees.

Removal of various foreign substances

Some foreign objects have been removed include metal pot lids and spray cans that could explode.…。

One veil is 250kg!

After removing foreign substances, plastic resources are compressed to form a lump (veil) and transported to a recycling facility. In order to efficiently recycle large amounts of plastic resources, the volume is reduced to about one-tenth.

Interview with Suzuki Plant Manager

Manager, Suzuki Plant

― What are the difficulties in sorting and compressing plastic resources?

　The most difficult part is the separation of lithium-ion batteries. With the spread of e-cigarettes, handicap fans, and mobile batteries, lithium-ion batteries are becoming more common. We have introduced a lithium buster, an X-ray separation device that detects lithium-ion batteries mixed in plastic resources, but it is difficult to separate everything. When the lithium buster reacts, humans manually remove foreign matter. This is a very difficult task.

　If lithium-ion batteries are mixed in, it may lead to fire in the factory. In the unlikely event of a fire, we will not be able to accept plastic resources.

― Please tell me the points that citizens should be aware of when separating plastic resources.

　Because it comes out every day, check not only your appearance, but also what is inside. I think it is important to know where lithium-ion batteries can be recycled, such as taking them to a nearby collection station.
Click here for how to put out small rechargeable batteries (lithium-ion batteries, mobile batteries, etc.)

　If you work together with Yokohama citizens, you may be able to recycle all things! Thank you for separating plastic resources at home.

[Resonac Corporation]

　Next, we will introduce the flow of "recycling facilities" that process veils (clumps of plastic resources) made at "intermediate treatment facilities" and recycle them into new products.

■Processed from veil (a mass of plastic resources) into molded plastic
　The veils made in the intermediate treatment facility are crushed finely with a crusher. The magnetic separator removes foreign matter, and the crushed veil is processed into a rod-shaped "mold plastic" with a molding machine to facilitate pyrolysis in the gasification facility process.
　In the process of crushing the veil, foreign substances that could not be removed at the intermediate treatment facility are also removed. By sorting using magnetic force, it detects foreign matter that has been mixed in. The contamination of such foreign matter can cause damage to the machine or fire.
※For more information, please refer to the following link.

Source: Resonac Corporation

Examples of foreign substances mixed (empty cans, can lids, can sprays, etc.)

(Left) Crushed veil (Right) Crushed veil is processed into a stick shape.

■Production from molded plastic to chemical raw materials
　"Molding plastic" processed in the crushing molding process is put into the low-temperature gasification furnace and high-temperature gasification furnace in gasification equipment, and pyrolysis is performed to transform it into "ammonia" and "carbon dioxide gas and dry ice".

Source: Resonac Corporation

Gasification facilities that pyrolysis at high temperatures

Interview with General Manager Ito, Plastic Chemical Recycling Promotion Office

General Manager, Ito

― In the first place, what is "chemical recycling"?
　Although it is a less-known recycling method, chemical recycling does not burn used plastics and restore almost everything as a variety of products. For example, it will be reborn as "textile material for clothing" made from ammonia raw materials, "carbon dioxide gas" used for beverages, and "dry ice" used for cooling.

― Do you have any difficulties in the process of using chemical raw materials?
　A variety of things other than plastic are mixed in. In particular, lithium-ion batteries are so popular and convenient, but if they are not properly separated, they may ignite in the factory. The plant produces 180 to 200 tons per day, but there is a high risk of destroying large machinery.

― If there is anything that we want citizens to cooperate, please.
　If you sort plastic neatly, it will be reborn as a resource! 。 I hope that you understand that the recycle bin at home is not just a recycle bin, but a recycling box, and that you can participate in the creation of this "mechanism". The child who was able to tour the factory was interested and seems to be working as a "recycle Gmen" at home. The most understanding is to actually see it, so please feel free to come to the factory tour.

　Plastic resources from homes are transformed into new products through human hand work and many processes. By observing the state of recycling this time, I felt the importance of properly separating garbage from home.
　Also, as Mr. Suzuki and Mr. Ito said, the number of lithium-ion batteries mixed in with the spread of small rechargeable batteries such as mobile batteries is also increasing. In addition to preventing accidents, I realized again that it was important to check how to put out small household appliances again in order to realize recycling. Click here for information on how to put out small household appliances.

What we can do

　In addition, in order to use plastic in an environmentally friendly manner, it is important to practice what each of us can do in our daily lives.

・Use of My Bag ・・・・・・・・・ Hold my bag and do not get shopping bags
・Use of My Bottles: Hold My Bottles and reduce the use of PET bottles
・Disposable tableware is NO!　・・・・・・・・ Do not get disposable tableware such as plastic straws, spoons and forks.
・Thorough sorting: ・・・・・・・・・・・・ Use of store collection and voluntary collection by businesses in the recycle bin properly.
・Increase plastic resources: Smooth or wipe off dirty plastic as much as possible to recycle it.
・Unnecessary plastic reduction: Select refill products or simple packaging products.

If you are unsure about how to separate plastic resources, you can search using the garbage collection by category search system "MIctionary" (external site).

　
　Plastic is a convenient thing. I think it is important to use the minimum necessary, use it carefully for a long time, and properly separate and process it. In order to protect the global environment in the future, it is necessary to review it from daily life. Because it is a large city Yokohama with about 3.7 million people, the actions of each and every citizen will have a great effect. Why don't you tackle environmental issues from what you can do every day?