Conditioning of a Na-bearing waste stream from the decomissioning of Na-cooled fast reactor set-ups

The remnants of the sodium-cooled fast reactor test campaigns performed at SCK CEN are to be treated in a joint decommissioning effort between SCK CEN and Belgoprocess. In an established chemical passivation process, the contaminated sodium and eutectic sodium-potassium are converted into stable carbonate form. However, there is no established waste management and disposal route for this formed carbonate.

The internship will evaluate suitable conditioning methods to process said carbonate waste. Cementation is investigated as a potential conditioning strategy, whereby the waste loading within the waste forms is optimized while safeguarding compliance to a selection of waste form acceptance criteria. The focus of the internship will be on the experimental synthesis and the characterization of the waste forms. 

The research will provide recommendations for the optimal conditioning strategy for chemically passivated sodium and potassium waste, allowing for the finalisation of the chemical process in light of the targeted concentration of the formed carbonate.