Thermal analysis of a fuel cladding repository pilot plant in salt

Technical Report · Thu Apr 01 04:00:00 EST 1976

DOI:https://doi.org/10.2172/7192097· OSTI ID:7192097

Claiborne, H C

Hulls remaining after chop-leach recovery of fuel from spent fuel elements are high level with respect to radiation but rather low level with respect to thermal power. Design criteria for a pilot plant for these wastes include retrievability and ready access to the rooms for several years, a condition that restricts the maximum floor temperature to less than 110/sup 0/F, probably 100/sup 0/F. Initial planning calls for waste canisters to be 15 ft long made from standard 12-in. steel pipe, with the hulls compacted to near 70% theoretical density. The canisters would be emplaced in 20-in.-dia holes in the salt floor of an excavated room. The empty space would be filled with sand to facilitate retrievability. It was assumed that the canisters were filled with PWR fuel hulls, which had a heat generation rate of 0.35 kW per canister when 1 year old. Two-dimensional thermal calculations for a unit cell were made to determine the effects of pitch, burial depth, waste age, and canister stacking on the max mine floor temperature. The waste must be aged about 7 years in order for the maximum floor temperature not to exceed 100/sup 0/F when single canisters are buried 15 ft deep in an array with a 4-ft square pitch. In the case of two canisters stacked vertically with a 5-ft sand-filled separation distance, at least a 4.5-ft pitch and an age of 10 years are required for a burial depth of 5 ft. For selected max floor temperatures, the required excavation of salt per waste canister (rooms plus canister holes) varies inversely with waste age, burial depth, and number of canisters. (DLC)

• Research Organization: Oak Ridge National Lab., Tenn. (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 7192097
• Report Number(s): ORNL/TM-5221
• Country of Publication: United States
• Language: English

Related Subjects

052002* -- Nuclear Fuels-- Waste Disposal & Storage
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
CONTAINERS
DECAY
DECLADDING
ENERGY TRANSFER
EXCAVATION
FUEL CANS
FUNCTIONAL MODELS
GEOLOGIC DEPOSITS
HEAD END PROCESSES
HEAT TRANSFER
MANAGEMENT
PILOT PLANTS
PWR TYPE REACTORS
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTE STORAGE
REACTORS
SALT DEPOSITS
STORAGE
TWO-DIMENSIONAL CALCULATIONS
UNDERGROUND DISPOSAL
WASTE DISPOSAL
WASTE MANAGEMENT
WASTE STORAGE
WATER COOLED REACTORS
WATER MODERATED REACTORS