Semianalytical Solutions of Radioactive or Reactive Transport in Variably-Fractured Layered Media: 1. Solutes

Moridis, George J.

United States. Department of Energy. Yucca Mountain Project Office.

关键词: Solutes;    Diffusion;    Radionuclide Migration;    Sorption;    Chemical Reactions;   

DOI  :  10.2172/805441
RP-ID  :  NONE
RP-ID  :  AC03-76SF00098
RP-ID  :  805441

美国|英语

来源: UNT Digital Library

【 摘 要 】

In this paper, semianalytical solutions are developed for the problem of transport of radioactive or reactive solute tracers through a layered system of heterogeneous fractured media with misaligned fractures. The tracer transport equations in the non-flowing matrix account for (a) diffusion, (b) surface diffusion, (c) mass transfer between the mobile and immobile water fractions, (d) linear kinetic or equilibrium physical, chemical, or combined solute sorption or colloid filtration, and (e) radioactive decay or first-order chemical reactions. The tracer-transport equations in the fractures account for the same processes, in addition to advection and hydrodynamic dispersion. Any number of radioactive decay daughter products (or products of a linear, first-order reaction chain) can be tracked. The solutions, which are analytical in the Laplace space, are numerically inverted to provide the solution in time and can accommodate any number of fractured and/or porous layers. The solutions are verified using analytical solutions for limiting cases of solute and colloid transport through fractured and porous media. The effect of important parameters on the transport of {sup 3}H, {sup 237}Np and {sup 239}Pu (and its daughters) is investigated in several test problems involving layered geological systems of varying complexity.