Redox control of electric melters with complex feed compositions. Part I: analytical methods and models

Conference · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5401786

Bickford, D F; Diemer, Jr, R B

The redox state of glass from electric melters with complex feed compositions is determined by balance between gases above the melt, and transition metals and organic compounds in the feed. Part I discusses experimental and computational methods of relating flowrates and other melter operating conditions to the redox state of glass, and composition of the melter offgas. Computerized thermodynamic computational methods are useful in predicting the sequence and products of redox reactions and in assessing individual process variations. Melter redox state can be predicted by combining monitoring of melter operating conditions, redox measurement of fused melter feed samples, and periodic redox measurement of product. Mossbauer spectroscopy, and other methods which measure Fe(II)/Fe(III) in glass, can be used to measure melter redox state. Part II develops preliminary operating limits for the vitrification of High-Level Radioactive Waste. Limits on reducing potential to preclude the accumulation of combustible gases, accumulation of sulfides and selenides, and degradation of melter components are the most critical. Problems associated with excessively oxidizing conditions, such as glass foaming and potential ruthenium volatility, are controlled when sufficient formic acid is added to adjust melter feed rheology.

• Research Organization: Du Pont de Nemours (E.I.) and Co., Aiken, SC (USA). Savannah River Lab.; Du Pont de Nemours (E.I.) and Co., Wilmington, DE (USA). Engineering Dept.
• DOE Contract Number: AC09-76SR00001
• OSTI ID: 5401786
• Report Number(s): DP-MS-85-16A; CONF-850755-3; ON: DE85016453
• Country of Publication: United States
• Language: English

Related Subjects

052001* -- Nuclear Fuels-- Waste Processing
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
BOROSILICATE GLASS
CATIONS
CERAMIC MELTERS
CHARGED PARTICLES
CHEMICAL REACTIONS
ELECTRIC FURNACES
ELEMENTS
FURNACES
GLASS
HIGH-LEVEL RADIOACTIVE WASTES
IONS
IRON
MATERIALS
METALS
OPERATION
RADIOACTIVE MATERIALS
RADIOACTIVE WASTES
REDOX REACTIONS
TRANSITION ELEMENTS
VALENCE
VITRIFICATION
WASTES