Construct Hokkaido

This page shows articles that have appeared in the Hokkaido Kensetsu Shimbun (Hokkaido Construction Journal) that have been translated into English.

More articles in English here.

Fixing Waste Plastic in Concrete: Aizawa High Pressure Concrete Jointly Develops the Technology with a US Company

2021年09月27日 07時00分

Aizawa High Pressure Concrete (Headquarters: Tomakomai) has signed a joint development agreement with MiCon Technology in the United States for immobilization technology with which waste plastic modified with gamma rays is used as a substitute for sand when making concrete. They are targeting practical use by the spring of 2023. Since waste plastic is reused as a material rather than being used as fuel, CO2 emissions can be expected to be reduced. It is likely to attract attention as a technology that will lead to decarbonization and environmental improvement.

Applying plastic reforming technology developed from basic research at the Massachusetts Institute of Technology (MIT), waste plastic is fixed inside concrete. MiCon Technology is a MIT startup, where Professor Olar Bucasterk, who is an authority on the development of sustainable cement-based materials, serves as CTO (Chief Technology Officer), and Dr. Cave Bactary, who conducts research on material processing technology, serves as CEO (Chief Executive Officer).

MiCon Technology has strengths in basic research on waste plastic use in concrete production. Crushed waste plastic is irradiated with gamma rays in a special method to modify the surface, and thereby the waste plastic can be used as a substitute for fine aggregate without impairing the physical characteristics. Aizawa High Pressure Concrete started technical exchanges with MiCon Technology in 2019 and has proceeded with technical verification and commercialization surveys through the Aizawa Institute of Technology.

Technical verification has revealed that about 5 kg of waste plastic (equivalent to 200 500 ml PET bottles) per m3 of concrete can be used as a substitute for fine aggregate. It reportedly leads to semi-permanent fixation of 13 kg of CO2 generated during incineration.

When crushed plastic with deteriorated quality is added to concrete, it adversely affects the freshness of concrete, causing a concern that the strength may deteriorate after curing. The Aizawa Institute of Technology has confirmed the potential to bring out the same or higher concrete strength by using MiCon’s reforming technology and a mixture with materials such as silica fume, which can be expected to increase strength.

In the future, they plan to develop a container-type module equipped with an electron beam irradiator that has the same modification effect as gamma ray irradiation and has a high processing speed. The dimensions of containers are set as world standards, and it is easy to install, move and combine containers. They are considering increasing or decreasing the number of modules according to the amount of waste plastic collected, or reusing the modules according to the operating rate.

About 8.5 million tons of waste plastic are collected annually in Japan, of which 69% is incinerated. Meanwhile, China announced a ban on imports of waste plastics in 2017, and regulations have also been introduced in Southeast Asia and Taiwan. As a result, there are increasingly fewer places for Japan to send its waste plastics.

President Yoshihiro Aizawa says, “We will be able to flexibly develop a waste plastic material recycling system in which residents, collectors, and concrete manufactures work together. By increasing the strength, it is possible to strategically reduce the amount of cement used, and it is expected that CO2 will be reduced during cement manufacturing.”

(Excerpt from an article on July 15, 2021)


Construct Hokkaido 一覧へ戻る

More articles in English here.

Contact us

ヘッドライン

ヘッドライン一覧 全て読むRSS

北海道建設新聞社新卒・キャリア記者採用募集バナー
  • 北海道水替事業協同組合
  • 東宏
  • 日本仮設

お知らせ

閲覧数ランキング(直近1ヶ月)

セントラルリーシング、千歳に複合レジャー拠点
2023年02月24日 (20,452)
イオン新店舗周辺の3路線を改良 室蘭市が24年度着...
2023年02月24日 (14,760)
真駒内地区義務教育学校、24年秋ごろ着工
2023年02月27日 (5,092)
ラピダスが千歳に半導体工場建設へ
2023年02月27日 (4,426)
来場者の五感を刺激 エスコンフィールド内覧会で実感
2023年03月11日 (3,876)

連載・特集

英語ページスタート

construct-hokkaido

連載 おとなの養生訓 new

おとなの養生訓
第251回「マスクの使い方」。換気がよい戸外ではそろそろ外しても大丈夫です。

連載 本間純子
いつもの暮らし便

本間純子 いつもの暮らし便
第30回「春を待つ街路樹」。街を彩り、運転をしやすくする、景観のお助けアイテムとも言えます。

連載 行政書士
池田玲菜の見た世界

行政書士池田玲菜の見た世界
第28回「『学び直し』の機会提供」。職場内の意識が改革され、多様性が取り入れられます。

連載 北海道開発事業費
見え始めた未来像
2023年度

迫る巨大地震
2023年度の北海道開発事業費を検証しながら、本道建設業の課題を整理する。