Modeling of brine migration in halite

Conference · Fri Oct 19 00:00:00 EDT 1979

OSTI ID:5607969

Cheung, H; Fuller, M E; Gaffney, E S

When canisters containing radwastes are emplaced in a repository the heat produced by the decaying radwaste will cause moderate thermal gradients to develop which will cause the brine present in a halite medium (salt deposits) to accumulate around the canister. Four different models of the migration process have been reviewed to determine their suitability as a working model. One model predicts that inclusions smaller than 0.1 mm dimension probably will not migrate. The other models do not consider size as a factor. Thermal diffusion (Soret effect) is considered insignificant in three models, while in the fourth model it is added to the concentration diffusion term. The following conclusions can be made: Temperature is the most significant parameter in all models and must be known as a function of time, and distance from the canister. All four models predict about the same migration velocity for it is a given set of conditions; for 100/sup 0/C and 1/sup 0/C/cm thermal gradient, it is 3.0, 4.8, 5.6 and 6.4 mm/y. Diffusion of ions through the brine inclusions is the rate controlling mechanism. The difference between the thermal gradients in the liquid and in the solid should always be considered and is a function of droplet shape. The model based upon work by Nernst is easiest to use, but it predicts the lowest migration rate. The maximum volume of pure brine accumulated at the canister surface would be less than 20-40 liters in 50 years, for a canister initial thermal power of 3.5 kW.Bitterns would migrate proportionately less volume. A computer code, BRINE, was developed to make these calculations by means of any of the four models.

• Research Organization: California Univ., Livermore (USA). Lawrence Livermore Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5607969
• Report Number(s): UCRL-82228(Rev.1); CONF-791112-53; TRN: 80-006433
• Resource Relation: Conference: Symposium on the scientific basis for nuclear waste management, Boston, MA, USA, 26 Nov 1979
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
BRINES
DIFFUSION
RADIOACTIVE WASTE STORAGE
TEMPERATURE GRADIENTS
B CODES
COMPUTER CODES
CONTAINERS
MATHEMATICAL MODELS
SALT DEPOSITS
THERMAL DIFFUSION
UNDERGROUND STORAGE
GEOLOGIC DEPOSITS
MANAGEMENT
STORAGE
WASTE MANAGEMENT
WASTE STORAGE
052002* - Nuclear Fuels- Waste Disposal & Storage