summary

This service uses oyster shells to remedy the deterioration of bottom sediment environments caused by persistent organic matter (sludge) deposited in bays and other locations. By mixing oyster shells with bottom sediment, the generation of hydrogen sulfide, which is harmful to organisms, is suppressed and the habitat of benthic organisms is restored. Benthic organisms are food for useful fish species, and recovery of useful fish species is also expected. This is a recycling-oriented environmental restoration method that both restores fishing grounds and marine resources.

Technical Strengths

Oyster shells treated with hot air drying have the ability to suppress the generation of hydrogen sulfide for a long period of time when mixed into the seabed. Although it is a natural material, it has a high environmental restoration effect and has been proven to last for approximately 5 years. It also has the advantage of resource recycling in that oyster shells produced in the ocean are effectively utilized in the ocean again.

Case Studies (Including Demonstration Results)

Provided to

Watershed Area Environmental Restoration Center

Case Studies

This project aims to restore an environment where a variety of organisms can live by mixing oyster shells, which purify sludge, into approximately 26,000 m2 of mud flats in Mitsu Bay, Akitsu-cho, Higashihiroshima City, Hiroshima Prefecture, to improve bottom sediment and water quality.

Other Case Studies

In 2022, the Boy Scouts of Japan Foundation undertook a project to upcycle plastic pipes for oyster farming into shopping baskets with the support of the 7-Eleven Memorial Foundation. The baskets are made from oyster pipes collected by children in Suo-Oshima, Yamaguchi Prefecture, and are being used at 7-Eleven stores currently exhibiting at the Osaka-Kansai Expo in 2025.