Radionuclide transport in fractured porous media -- Analytical solutions for a system of parallel fractures with a kinetic solubility-limited dissolution model

Journal Article · Sat Nov 01 04:00:00 EST 1997 · Nuclear Technology

OSTI ID:562064

Li, S H; Chen, C T ^[1]

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1. National Tsing Hua Univ., Hsinchu (Taiwan, Province of China). Dept. of Nuclear Engineering and Engineering Physics

Analytical solutions are developed for the problem of radionuclide transport in a system of parallel fractures situated in a porous rock matrix. A kinetic solubility-limited dissolution model is used as the inlet boundary condition. The solutions consider the following processes: (a) advective transport in the fractures, (b) mechanical dispersion and molecular diffusion along the fractures, (c) molecular diffusion from a fracture to the porous matrix, (d) molecular diffusion within the porous matrix in the direction perpendicular to the fracture axis, (e) adsorption onto the fracture wall, (f) adsorption within the porous matrix, and (g) radioactive decay. The solutions are based on the Laplace transform method. The general transient solution is in the form of a double integral that is evaluated using composite Gauss-Legendre quadrature. A simpler transient solution that is in the form of a single integral is also presented for the case that assumes negligible longitudinal dispersion along the fractures. The steady-state solutions are also provided. A number of examples are given to illustrate the effects of the following important parameters: (a) fracture spacings, (b) dissolution-rate constants, (c) fracture dispersion coefficient, (d) matrix retardation factor, and (e) fracture retardation factor.

• OSTI ID: 562064
• Journal Information: Nuclear Technology, Journal Name: Nuclear Technology Journal Issue: 2 Vol. 120; ISSN 0029-5450; ISSN NUTYBB
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
54 ENVIRONMENTAL SCIENCES
ANALYTICAL SOLUTION
FRACTURED RESERVOIRS
HIGH-LEVEL RADIOACTIVE WASTES
POROUS MATERIALS
RADIOACTIVE WASTE DISPOSAL
RADIONUCLIDE MIGRATION
UNDERGROUND DISPOSAL