Cements of the future to use in immobilising the nation's nuclear wastes and future nuclear cements.

The use of cements in nuclear waste treatment, decommissioning and disposal activities in the UK will extend to 2070 and beyond, including grouting of wasteforms and backfilling of the proposed Geological Disposal Facility. Current plans and feasible options for these activities are based around the assumption that the materials currently in use - particularly Portland cement, ground granulated blast furnace slag, and pulverised fuel ash - will continue to be available throughout this timeframe. However, this availability is far from certain, as the cement, iron and coal industries continue to undergo structural and technical changes, and material supply shifts from UK producers to overseas sources. The core purpose of this PhD project is to assess the likely future availability of cement powders and related materials, as well as potential future alternatives, to enable the UK industry to position itself appropriately to respond proactively to changes in materials availability. This project couples the core EPSRC areas of "Manufacturing the Future", "Nuclear Fission" and "Materials Engineering", also integrating aspects of "Built Environment" as related to future cements supply.
Construction accounts for more than 99% of all cement usage, and so will provide the key driver for future shifts in production, specifications and availability. The construction industry requires low cost, low CO2 emissions, high early strength, and a diversity of blended cement types, while the nuclear industry is far more sensitive to consistency of product characteristics and the ability to control flow, heat release and dimensional stability.
For these reasons, it is essential to assess the likely future of cement production and availability in the UK, in an 'optioneering' sense as well as with a view toward selection of materials which will offer the desired engineering characteristics while being available to the UK nuclear industry at reasonable cost. Laboratory testing of candidate cement materials, in partnership with industry, will be coupled with holistic (regional and global) analysis of trends and needs in the construction and nuclear sectors, to identify cementation options as a function of timescale and TRL, with indications of potential matches between cements and waste types within the UK inventory and future arisings.