Publications by authors named "Pavel Hrma"
The kinetics of the feed-to-glass conversion affects the waste vitrification rate in an electric glass melter. The primary area of interest in this conversion process is the cold cap, a layer of reacting feed on top of the molten glass. The work presented here provides an experimental determination of the temperature distribution within the cold cap.
View Article and Find Full Text PDFEffect of bubbles and silica dissolution on melter feed rheology during conversion to glass.
Environ Sci Technol
October 2014
Article Synopsis
- Nuclear-waste melter feeds are created from waste mixtures combined with additives to form glass, which are then melted in a furnace into a continuous glass melt.
- During the melting process, the initial mixture contains solid materials and gas bubbles, which eventually escape, leading to a uniform glass melt.
- The study focused on measuring the viscosity of the melter feed as it heats up, analyzing how the presence of quartz particles, gas bubbles, and compositional differences affect the viscosity.
The immobilization of technetium-99 ((99)Tc) in a suitable host matrix has proven to be a challenging task for researchers in the nuclear waste community around the world. In this context, the present work reports on the solubility and retention of rhenium, a nonradioactive surrogate for (99)Tc, in a sodium borosilicate glass. Glasses containing target Re concentrations from 0 to 10,000 ppm [by mass, added as KReO(4) (Re(7+))] were synthesized in vacuum-sealed quartz ampules to minimize the loss of Re from volatilization during melting at 1000 °C.
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