STUDY OF CORROSION ON VARIOUS METALS IN THE CALCINING OF AQUEOUS RADIOACTIVE WASTES CONTAINING ZIRCONIUM FLUORIDE AND ALUMINUM NITRATE AS BULK SALTS

Technical Report · Thu May 01 04:00:00 EDT 1958

OSTI ID:4280449

Tuthill, E J; Domish, R F

The calcination of bulk salts of Zr and Al in high level radioactive wastes to their stable oxides is a logical step toward ultimate disposal. The outstanding objectives here are to achieve maximum chemical stability and minimum volume. Since Zr wastes contain the bulk salts zirconium fluoride, aluminum fluoride, and aluminum nitrate, the calcination which requires temperatures up to 700 C obviously presents a serious problem with respect to corrosion of the container materials. The present study was undertaken for the purpose of measuring the resistance of certain selected materials to the corrosive conditions encountered in the calcination of simulated Zr waste solutions in rotary ball kilns. Two separate investigations were made: the first centered on the use of two kilns in series, and the second involved a single kiln. The purpose of using two kilns in the first investigation was to separate the oxides of nitrogen from the hydrogen fluorlde in the off-gases. Denitration was accomplished largely in the first kiln at temperatures below 400 and defluorination in the second kiln at temperatures above 700 C. The second investigation involving a single-kiln unit was made because several alloys had alrady shown favorable resistance to conditions encountered in the high temperature ( defluorination) unit of the double-kiln apparatus. Results of the study indicated that no advantage with respect to corrosion was realized by using the double-kiln apparatus, and that with either the single unit or the double unit design at least four alloys are probably suitable as materials of construction for calciner vessels. (auth)

• Research Organization: Brookhaven National Lab., Upton, N.Y.
• NSA Number: NSA-13-010838
• OSTI ID: 4280449
• Report Number(s): BNL-510
• Country of Publication: United States
• Language: English

Related Subjects

ALLOYS
ALUMINUM FLUORIDES
ALUMINUM NITRATES
ALUMINUM OXIDES
CALCINATION
CHEMISTRY
CORROSION
CORROSION PROTECTION
FURNACES
GASES
HIGH TEMPERATURE
HYDROFLUORIC ACID
METALS
NITROGEN OXIDES
PYROLYSIS
ROTATION
SEPARATION PROCESSES
STABILITY
TESTING
VESSELS
VOLUME
WASTE DISPOSAL
WASTE PROCESSING
WASTE SOLUTIONS
ZIRCONIUM FLUORIDES
ZIRCONIUM OXIDES