TAIPEI (Taiwan News) — The state-run Taiwan Sugar Corporation, or Taisugar, has made strides to upcycle oyster shells, as the country works to promote a circular economy and move towards a net-zero future.

A biotech plant owned by the company in Tainan has since June 2021 churned out 40,000 tons of calcium carbonate power annually from around 50,000 tons of discarded oyster shells. The waste is sourced from the country’s oyster industry, centered along the west coast.

Following a series of treatments involving calcination and processing, the waste turns into value-added materials that can be used for agricultural, industrial, and medical purposes.

Applications developed include fertilizer, animal feed, anti-bacteria plastics, 3D printing materials, soap, and cat litter. Other potential applications such as coating materials, thermal insulation materials, biodegradable plastic, and filter material are being experimented with, according to Taisugar.

Taiwan relies on rock imports or quarrying to extract calcium carbonate, or CaCO3. Transforming thrown-away shells into the compound not only helps meet the demand, but is also conducive to cutting waste and boosting revenue for oyster farmers, said the company.

Recycled oyster shells made into various products. (Taisugar photos)

Ground oyster shells in Taisugar's biotech plant. (Taisugar photo)