Treatment is about undertaking a process in order to change the characteristics or state of the waste. This could include reducing the volume, removing radionuclides from the material or changing its composition.
Typical treatment operations include incineration or compaction of dry solid waste or organic liquid wastes (volume reduction), filtration or ion exchange of liquid waste (radionuclide removal) and precipitation or flocculation of chemical species (change of composition).
In the same way that conditioning treatment is used to convert waste into a form that is suitable for subsequent management, treatment of the waste can involve minimisation of the volume or reduction of the hazard. Treatment can happen as several stages throughout the lifecycle and, depending on the waste being considered, several routes can be taken.
Chemical treatments can be used including decontamination, washing and leaching. High temperature treatments include melting, incineration and vitrification.
Physical treatments can involve lasers, super compaction and shredding, or immobilisation which includes entombment and grout encapsulation.
Case study
Thermal treatment
Significant progress has been made to investigate the use of thermal treatment technologies, delivering research and development to better understand the scale of potential benefits.
Thermal treatment technologies apply high temperatures to waste to destroy reactive components, reduce overall volumes and produce a stable waste form. The Thermal Treatment Integrated Project Team has carried out work to understand waste applicability, technology capability and economic aspects.
Demonstration trials have been undertaken using surrogate radioactive wastes to evaluate the technology and its ability to treat a range of wastes. Trials have successfully processed inactive and active waste simulant under nuclear site licence conditions on the Sellafield site. This work is the first of its kind in the UK and has confirmed that significant volume reduction and waste passivation can be achieved for ILW streams.
Work continues to address cultural and technical challenges, with a clear route to implementation of these technologies being developed.