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Title: Multi-phase reactive transport theory

Abstract

Physicochemical processes in the near-field region of a high-level waste repository may involve a diverse set of phenomena including flow of liquid and gas, gaseous diffusion, and chemical reaction of the host rock with aqueous solutions at elevated temperatures. This report develops some of the formalism for describing simultaneous multicomponent solute and heat transport in a two-phase system for partially saturated porous media. Diffusion of gaseous species is described using the Dusty Gas Model which provides for simultaneous Knudsen and Fickian diffusion in addition to Darcy flow. A new form of the Dusty Gas Model equations is derived for binary diffusion which separates the total diffusive flux into segregative and nonsegregative components. Migration of a wetting front is analyzed using the quasi-stationary state approximation to the Richards` equation. Heat-pipe phenomena are investigated for both gravity- and capillary-driven reflux of liquid water. An expression for the burnout permeability is derived for a gravity-driven heat-pipe. Finally an estimate is given for the change in porosity and permeability due to mineral dissolution which could occur in the region of condensate formation in a heat-pipe.

Authors:
 [1]
  1. Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses
Publication Date:
Research Org.:
Nuclear Regulatory Commission, Washington, DC (United States). Div. of Regulatory Applications; Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses
Sponsoring Org.:
Nuclear Regulatory Commission, Washington, DC (United States)
OSTI Identifier:
95551
Report Number(s):
NUREG/CR-6347; CNWRA-94-018
ON: TI95016096; TRN: 95:019361
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Jul 1995
Country of Publication:
United States
Language:
English
Subject:
05 NUCLEAR FUELS; RADIOACTIVE WASTE DISPOSAL; HEAT TRANSFER; MASS TRANSFER; POROUS MATERIALS; RADIOACTIVE WASTE FACILITIES; UNDERGROUND DISPOSAL; HIGH-LEVEL RADIOACTIVE WASTES; HYDROTHERMAL SYSTEMS; SOLUTES; YUCCA MOUNTAIN; Yucca Mountain Project

Citation Formats

Lichtner, P.C. Multi-phase reactive transport theory. United States: N. p., 1995. Web. doi:10.2172/95551.
Lichtner, P.C. Multi-phase reactive transport theory. United States. doi:10.2172/95551.
Lichtner, P.C. 1995. "Multi-phase reactive transport theory". United States. doi:10.2172/95551. https://www.osti.gov/servlets/purl/95551.
@article{osti_95551,
title = {Multi-phase reactive transport theory},
author = {Lichtner, P.C.},
abstractNote = {Physicochemical processes in the near-field region of a high-level waste repository may involve a diverse set of phenomena including flow of liquid and gas, gaseous diffusion, and chemical reaction of the host rock with aqueous solutions at elevated temperatures. This report develops some of the formalism for describing simultaneous multicomponent solute and heat transport in a two-phase system for partially saturated porous media. Diffusion of gaseous species is described using the Dusty Gas Model which provides for simultaneous Knudsen and Fickian diffusion in addition to Darcy flow. A new form of the Dusty Gas Model equations is derived for binary diffusion which separates the total diffusive flux into segregative and nonsegregative components. Migration of a wetting front is analyzed using the quasi-stationary state approximation to the Richards` equation. Heat-pipe phenomena are investigated for both gravity- and capillary-driven reflux of liquid water. An expression for the burnout permeability is derived for a gravity-driven heat-pipe. Finally an estimate is given for the change in porosity and permeability due to mineral dissolution which could occur in the region of condensate formation in a heat-pipe.},
doi = {10.2172/95551},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1995,
month = 7
}

Technical Report:

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