scholarly journals THOREX processing and zeolite transfer for high-level waste stream processing blending

1997 ◽  
Author(s):  
S. Jr. Kelly ◽  
D.C. Meess
Keyword(s):  
Stream Processing ◽  
Waste Stream ◽  
High Level Waste ◽  
High Level

Immobilization of high-level waste in ceramic waste forms

1986 ◽  
Vol 319 (1545) ◽  
pp. 63-82 ◽  
Keyword(s):  
Borosilicate Glass ◽  
Nuclear Industry ◽  
Waste Stream ◽  
High Level Waste ◽  
Phase Assemblage ◽  
Crystal Lattices ◽  
Ceramic Waste ◽  
Waste Forms ◽  
Wide Range ◽  
High Level

High-level wastes (HLW) can be incorporated in the crystal lattices of coexisting phases in ceramic waste forms. The properties and performances of ceramic waste forms are largely determined by their phase chemistry, phase assemblage and microstructure. Currently, the best categorized advanced ceramic waste form is SYNROC, a titanate ceramic composed of ‘ hollandite ’ Bat 1(Al,Ti)2^Ti|]*"70 16, zirconolite CaZrTi 2 O 7 , perovskite CaTiO 3 , rutile TiO 2 and minor amounts of metal alloys microencapsulated by the titanate matrix. Two factors contribute to the capacity of synroc to accommodate high (e.g. 20% ) loadings of HLW, together with variations in waste-stream composition. Firstly, the constituent phases can accept, as solid solutions in their crystal lattices, a broad spectrum of cationic species of diverse charge and radius, either singly or by complex substitution mechanisms. Secondly, the phase assemblage itself spontaneously adjusts its modal mineralogy in response to waste stream fluctuations. The presence of both rutile and a source of trivalent titanium (from reaction of rutile with added Ti metal) in the synroc phase assemblage is largely responsible for this flexible and accommodating nature. The titanate minerals in synroc also occur in Nature, where they have survived for many millions of years in a wide range of geological environments. Experimental studies show that synroc is vastly more resistant to leaching by groundwater than borosilicate glass; moreover, its high leach resistance is maintained at elevated temperatures. Experimental and analogue studies indicate that the HLW immobilization properties of synroc are not significantly impaired by radiation damage. These properties show that synroc would provide an effective immobilization barrier for HLW when buried in suitable repositories. They also permit the use of a wider range of geological disposal options than are appropriate for borosilicate glass. In particular, synroc is well suited for disposal in deep drill-holes, both in continental and marine environments. The fact that synroc is composed of minerals that have demonstrated long-term geological stability is important in establishing public confidence in the ability of the nuclear industry to immobilize high-level wastes for the very long periods required.

Effects of Aging on the Solubility of Palladium

1995 ◽  
Vol 412 ◽  
Author(s):  
C. Oda ◽  
H. Yoshikawa ◽  
M. Yui
Keyword(s):  
Aqueous Solution ◽  
Aging Time ◽  
Room Temperature ◽  
High Level Waste ◽  
Anaerobic Conditions ◽  
Dilute Aqueous Solution ◽  
Waste Repository ◽  
Ph Range ◽  
Effects Of Aging ◽  
High Level

AbstractPalladium solubility was measured in a dilute aqueous solution at room temperature in the pH range from 3 to 13 under anaerobic conditions. Crystalline Pd metal was clearly visible and the concentration of palladium in solution decreased gradually with aging time. The palladium concentrations in solution were less than 9.4×10-10M in the pH range from 4 to 10 and increased to 10-7M in the pH range greater than 10. This study suggests that palladium concentrations in certain high-level waste repository environments may be limited by Pd metal and may be less than 10-9M.

Performance assessment of the disposal of vitrified high-level waste in a clay layer

2001 ◽  
Vol 298 (1-2) ◽  
pp. 125-135 ◽  
Author(s):  
Dirk Mallants ◽  
Jan Marivoet ◽  
Xavier Sillen
Keyword(s):  
Performance Assessment ◽  
High Level Waste ◽  
Clay Layer ◽  
High Level

Use of microwave energy in reprocessing of high-level waste

Atomic Energy ◽  
1992 ◽  
Vol 73 (3) ◽  
pp. 730-734 ◽  
Author(s):  
A. A. Kurkumeli ◽  
M. I. Molokhov ◽  
O. D. Sadkovskaya ◽  
V. I. Kononov ◽  
G. B. Borisov ◽  
...  
Keyword(s):  
Microwave Energy ◽  
High Level Waste ◽  
High Level

Recovery of actinides extracted by Truex solvent from high level waste using complexing agents

1999 ◽  
Vol 240 (3) ◽  
pp. 727-730 ◽  
Author(s):  
R. R. Chitnis ◽  
P. K. Wattal ◽  
A. Ramanujam ◽  
P. S. Dhami ◽  
V. gopalakrishnan ◽  
...  
Keyword(s):  
High Level Waste ◽  
Complexing Agents ◽  
High Level
Sign in / Sign up

Export Citation Format

Share Document