Safe, efficient cementation of challenging radioactive wastes using alkali activated materials with high-flowability and high-anion retention capacity

In this project, we will collaboratively develop, optimise and scale-up new high-performing geopolymer cements for use in the solidification of sludge wastes that have been generated in the Fukushima Daiichi cleanup and remediation process. These wastes contain a complicated and problematic combination of radioactive elements, and are currently stored in containers awaiting final treatment (conditioning). Before the wastes can be disposed, they must be converted to a solid form, but the conventional cement blends that would usually be used for this purpose require modification or improvement so that they can give appropriate performance in making the wastes safe. For this reason, we will develop, optimise, and scale-up a set of bespoke, innovative geopolymer-type cements, produced from aluminosilicate clays, to give excellent fluidity and mixing characteristics that will enable them to be fully effective in solidifying the sludges, and outstanding performance in the long-term to prevent the release of immobilised radioactive materials. We will determine key new fundamental scientific aspects that control the materials science and chemistry of geopolymer cements in combination with iron-rich sludges, which will bring new understanding of these materials that can also be transferred to benefit other uses of geopolymer cements in nuclear and non-nuclear applications. We will work in partnership with industry to demonstrate these materials, and the associated processes for their usage, at a scale that is large enough to validate the use of this new procedure directly in the Fukushima cleanup operations. In this way, we will use advanced materials science to benefit future generations.

This project will lead to the development of geopolymer technology as a highly effective and safe method for the conditioning of problematic sludges that result from nuclear remediation and decommissioning operations. This will generate impact by making available a new process, demonstrated at a useful pilot scale, for the treatment and safe long-term disposition of the problematic iron hydroxide sludge that has been generated in large quantities at the Fukushima Daiichi site. To enhance uptake and maximise the value of the project results, we will:
* conduct a major scale-up campaign led by a Japanese company (ADVAN ENG Co. ltd), to prove the material and process solutions at a realistic pilot scale
* engage directly with government bodies in Japan and site licence companies in the UK to maximise the utility of our results in both nations
* connect and interact with other UK-Japan projects and international activities in related topics, to ensure maximum synergy
* disseminate our work in the highest-profile journals and conferences to reach an academic audience
* host and run industry-focused workshops in Japan, continuing our past successes in this area, to raise visibility of our work among key decision-makers
* train excellent early-career researchers to world-best levels, helping to secure the future of nuclear research in Japan and the UK