The impacts of waste materials utilization in liquid radioactive waste solidification by mortar matrix

The nuclear industry generates significant radioactive waste (RW) amounts, with its safe disposal being a primary safety and environmental issue. RW management involves solidification and disposal, often in deep underground facilities. Cement mortar is commonly used for liquid RW solidification due to its cost-effectiveness and simplicity. However, Portland cement concrete production raises environmental concerns, such as CO2 emissions and natural resource depletion. Additionally, RW storage and disposal costs drive research into low-cost matrices, especially those made from final waste products. The main requirements for matrix materials for liquid RW immobilization, which accept the role of primary barrier, are compatibility with RW material, good mechanical properties, and resistance to chemical and biological agents. However, partially substituting cement with waste materials can reduce strength and durability, increase susceptibility to cracking, porosity, and corrosion, further leading to harmful substance release. The matrix material must demonstrate longterm stability under various environmental conditions, including changes in temperature, humidity, and exposure to radiation ensuring that RW remains stable and safe within the matrix for decades or centuries. In addition, factors such as groundwater infiltration and seismic activity should also be considered when evaluating the long-term effectiveness of a protective structure. To manage these hazards, the selection, treatment, and preparation of recycled waste are crucial, alongside with proper design and utilization of such concrete. Monitoring concrete performance over time and implementing maintenance measures are necessary to ensure the long-term durability and reliability of structures. This work aims to assess the overall impact of recycled materials utilized in liquid RW solidification matrix.