RIKEN TECHNOS Collaborates with Waseda University and MIDAC Holdings to Develop Resin Products Using Calcium Carbonate Derived from Leachate Generated at the Final Disposal Sites of Industrial Waste

RIKEN TECHNOS CORPORATION (Head Office: Chiyoda-ku, Tokyo; Representative Director, President & CEO: Kazuaki Tokiwa) has collaborated with the Waseda Geotechnical Laboratory of Waseda University and MIDAC Holdings Co., Ltd. to develop resin products using calcium carbonate derived from leachate generated at the final disposal sites of industrial waste. They are also working to develop technologies that achieve effective use of carbon dioxide (CO₂) and sustainability at the same time.

RIKEN TECHNOS manufactures and sells compound products made from polyvinyl chloride (PVC) and thermoplastic elastomers while also operating in a wide range of other fields such as film products. Calcium carbonate is one of the various fillers that we use to control the properties of these compound products.

According to the Life Cycle Assessment (LCA) method^*, calcium carbonate is recognized as a low environmental impact material. It is a commonly used material obtained mainly through mining, but it can also be manufactured through a range of other methods. One of those methods produces the calcium carbonate at the final disposal sites of industrial waste. Leachate generated at these sites undergoes various treatments before release into the natural environment via the river system to ensure there are no adverse environmental effects. As part of those treatments, calcium ions in the leachate are reacted with carbonate ions to remove them as calcium carbonate. However, until now, the resulting calcium carbonate was just disposed of. In addition, CO₂ released when incinerating industrial waste can be used as the source of these carbonate ions. This not only enables the removal of calcium ions in leachate, but also offers a potential approach for the effective use of CO₂, which is one cause of global warming.

Against this background, the Waseda Geotechnical Laboratory of Waseda University (material analysis and initial evaluation), MIDAC Holdings Co., Ltd. (supply of material from final disposal sites and process review), and RIKEN TECHNOS (product development and safety evaluation) have been collaborating to investigate utilization of the calcium carbonate generated at final disposal sites for industrial applications.

After investigating the potential for using this calcium carbonate as a resin filler, we found that it could be used in the same ways as commercially available calcium carbonate.

The result was a proposal for a business model that solved three social issues at once—global environmental issues, local environmental issues, and resource circulation. Going forward, we will establish a scheme for commercial use of calcium carbonate from final disposal sites while also investigating its use in PVC and various other resins.

Through practical application of resin products that simultaneously achieve effective use of CO₂ and sustainability, RIKEN TECHNOS will contribute to realizing a sustainable society.

We also plan to exhibit these developed products at the Automotive Engineering Exposition 2026 YOKOHAMA, to be held May 27–29, 2026, at PACIFICO Yokohama.

* Life Cycle Assessment (LCA) is a method for quantitatively evaluating environmental impacts across the entire life cycle of products and services, from material procurement to disposal and recycling.

Waseda Geotechnical Laboratory of Waseda University
https://hkomine.w.waseda.jp/

MIDAC Holdings Co., Ltd.
https://www.midac.jp/en/

Automotive Engineering Exposition 2026 YOKOHAMA
https://aee.expo-info.jsae.or.jp/en/yokohama/