CRITICALITY SAFETY OF PROCESSING SALT SOLUTION AT SRS

Conference · Tue Jan 15 04:00:00 EST 2008

OSTI ID:923438

Stephens, K; Davoud Eghbali, D; Michelle Abney, M

High level radioactive liquid waste generated as a result of the production of nuclear material for the United States defense program at the Savannah River Site has been stored as 36 million gallons in underground tanks. About ten percent of the waste volume is sludge, composed of insoluble metal hydroxides primarily hydroxides of Mn, Fe, Al, Hg, and most radionuclides including fission products. The remaining ninety percent of the waste volume is saltcake, composed of primarily sodium (nitrites, nitrates, and aluminates) and hydroxides. Saltcakes account for 30% of the radioactivity while the sludge accounts for 70% of the radioactivity. A pilot plant salt disposition processing system has been designed at the Savannah River Site for interim processing of salt solution and is composed of two facilities: the Actinide Removal Process Facility (ARPF) and the Modular Caustic Side Solvent Extraction Unit (MCU). Data from the pilot plant salt processing system will be used for future processing salt at a much higher rate in a new salt processing facility. Saltcake contains significant amounts of actinides, and other long-lived radioactive nuclides such as strontium and cesium that must be extracted prior to disposal as low level waste. The extracted radioactive nuclides will be mixed with the sludge from waste tanks and vitrified in another facility. Because of the presence of highly enriched uranium in the saltcake, there is a criticality concern associated with concentration and/or accumulation of fissionable material in the ARP and MCU.

• Research Organization: SRS
• Sponsoring Organization: DOE
• DOE Contract Number: AC09-96SR18500
• OSTI ID: 923438
• Report Number(s): WSRC-MS-2008-00001
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
ACTINIDES
ALUMINATES
CESIUM
CRITICALITY
FISSION PRODUCTS
FISSIONABLE MATERIALS
HIGHLY ENRICHED URANIUM
HYDROXIDES
ISOTOPES
LIQUID WASTES
NITRATES
NITRITES
PILOT PLANTS
RADIOACTIVITY
RADIOISOTOPES
REMOVAL
SAFETY
SAVANNAH RIVER PLANT
SLUDGES
SODIUM
SOLVENT EXTRACTION
STRONTIUM
TANKS
WASTES