Geochemical modelling of the alteration of a granitic rock around a repository for spent nuclear fuel

Conference · Wed Jan 01 04:00:00 EST 1986 · Mater. Res. Soc. Symp. Proc.; (United States)

OSTI ID:5366896

Fritz, B; Kam, M; Tardy, Y

The alteration of a granitic rock around a repository for spent nuclear fuel has been simulated considering the geothermal effect through an increase of temperature. The results of the simulation were considered in terms of mass transfers and their volumic consequences. The dissolution of primary minerals by alteration tends to increase the porous volume due to fissures and cracks, while the precipitation of secondary minerals and particularly here calcite and clay minerals will tend to decrease the porosity by sealing the cracks. The results of the simulations show that an increase of temperature from 10 to 100/sup 0/C will favor the alteration of the granitic rock by the solutions circulating today in the rock. This rock is characterized by a very low fissure porosity and the water velocity is consequently particularly low. These conditions favor intense water-rock interactions and the water-rock system will probably reach the stability field of secondary clay minerals predicted by the calculations: the porosity will decrease. A combination of these thermodynamic mass balance calculations and hydrodynamic considerations, with a kinetic approach of mineral dissolutions gives a first attempt to calibrate the modelling in the time scale.

• Research Organization: CNRS, Strasbourg, France
• OSTI ID: 5366896
• Report Number(s): CONF-850995-
• Conference Information: Journal Name: Mater. Res. Soc. Symp. Proc.; (United States) Journal Volume: 50
• Country of Publication: United States
• Language: English

Related Subjects

052002 -- Nuclear Fuels-- Waste Disposal & Storage
053000* -- Nuclear Fuels-- Environmental Aspects
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
510301 -- Environment
Terrestrial-- Radioactive Materials Monitoring & Transport-- Soil-- (-1987)
54 ENVIRONMENTAL SCIENCES
CHEMISTRY
DISSOLUTION
ENERGY SOURCES
ENVIRONMENTAL TRANSPORT
FUELS
GEOCHEMISTRY
GRANITES
IGNEOUS ROCKS
MANAGEMENT
MASS TRANSFER
MATERIALS
MINERALS
NUCLEAR FUELS
PLUTONIC ROCKS
POROSITY
RADIOACTIVE WASTE DISPOSAL
RADIONUCLIDE MIGRATION
REACTOR MATERIALS
ROCKS
SIMULATION
SPENT FUELS
TEMPERATURE DEPENDENCE
UNDERGROUND DISPOSAL
WASTE DISPOSAL
WASTE MANAGEMENT