Polyethylene encapsulation of single-shell tank low-level wastes. Annual progress report

Technical Report · Tue Sep 01 04:00:00 EDT 1992

DOI:https://doi.org/10.2172/10154920· OSTI ID:10154920

Kalb, P D; Fuhrmann, M; Cassidy, J; Colombo, P; Franz, E M; Fuhrmann, M; Heiser, J III; Kalb, P D; Klages, J; Pietrzak, R

This report describes work supported by the UST-ID, conducted at Brookhaven National Laboratory I (BNL), to develop and demonstrate a polyethylene waste encapsulation process for low-level radioactive (LLW) and hazardous mixed wastes (HMW) stored in underground tanks. During FY 1992, studies were completed on the effects of elevated temperature on waste form integrity, strength and leachability. No changes in waste form integrity or compressive yield strength were detected after storing polyethylene waste forms containing 50, 60 and 70 wt% sodium nitrate at 70{degree}C for 3 months. Leaching of polyethylene waste forms with similar nitrate salt loadings at temperatures up to 70{degree}C resulted in slight increases in leachability (< a factor of 2), compared with leaching at ambient temperatures. Leaching of sodium nitrate from polyethylene waste forms was diffusion-controlled, enabling extrapolation of laboratory leach data to full-scale waste forms over long time periods. Full-scale polyethylene waste forms containing 50 to 70 wt% nitrate salt could be expected to leach a total of 5% to 17% of the original contaminant source term after 300 years of leaching under worst-case (70{degree}C, fully saturated) conditions. This is about 25 to 75 times lower leachability than conventional cement grout waste forms containing a maximum of 20 wt% nitrate salts.

• Research Organization: Brookhaven National Lab., Upton, NY (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 10154920
• Report Number(s): BNL--52365; ON: DE93012805
• Country of Publication: United States
• Language: English

Related Subjects

052002
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
36 MATERIALS SCIENCE
360603
CESIUM 137
CHEMICAL ANALYSIS
COMPILED DATA
CORROSION
DIFFUSION
ENCAPSULATION
GROUTING
HANFORD RESERVATION
HAZARDOUS MATERIALS
IDAHO NATIONAL ENGINEERING LABORATORY
IRRADIATION
LEACHING
LOW-LEVEL RADIOACTIVE WASTES
MECHANICAL PROPERTIES
ORNL
POLYETHYLENES
PROGRESS REPORT
REMEDIAL ACTION
SALTS
SAVANNAH RIVER PLANT
SLUDGES
SODIUM NITRATES
STRONTIUM 90
TANKS
THERMAL TESTING
TRUEX PROCESS
WASTE DISPOSAL AND STORAGE
WASTE FORMS