The SNF is first dissolved and then passed through a series of centrifugal contractors in the first cycle, which removes high activity waste and Pu and U waste. Both the Pu and U waste streams are treated separately through a series of mixer settlers. An overview of the 221-F Canyon at SRS followed. It has been operating since November 1954 and disposes of legacy DOE material. It presently processes 40 MT U per month.
Jerry Christian, INEEL, described the dry chloride volatility processing concept. The process entails chlorination and volatilization of all fuel components at about 1800 K. This is followed by separation of the fission product from the gas stream by condensation and dissolution in a zinc chloride molten salt scrubber at 673 K. The vapors that pass through the scrubber are collected by fractional condensation at 437-275 K. The zinc chloride is then recycled by vacuum distillation at 1000 K.
Xiangdong Feng, PNL, presented information on a direct plasma arc-vitreous ceramic process. The plasma is generated by passing an electric current through a gas, leading to ionization. The plasma torch melts and oxidizes the SNF and sludge at high temperature (>12,000 ºC). The melt is homogenized through the rotating action of the tub and the depression caused by the plasma torch discharging. The melt is discharged from the furnace as the rotation of the tub slows.
After the final presentation, the meeting reverted to a closed session. The presentations were discussed, and writing assignments for the upcoming report were made. A date for the next two committee meetings was made, one for a closed meeting in Washington D.C. on April 27, and a second meeting in Idaho Falls on June 25-26. The first day of this meeting will be open.