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General form of the ADE:. sink/source term. Chemical sink/source term. Simple form of the ADE. Uniform 1D flow; longitudinal dispersion; sink/source term. General form of the ADE:. sink/source term. Chemical sink/source term. We will consider two types of chemical reactions
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General form of the ADE: sink/source term Chemical sink/source term
Simple form of the ADE Uniform 1D flow; longitudinal dispersion; sink/source term
General form of the ADE: sink/source term Chemical sink/source term
We will consider two types of chemical reactions • Sorption (adsorption & absorption) • 1st order irreversible reactions (radioactive decay, • hydrolysis, some forms of biodegradation)
sorption 1st order LEA (Zheng & Bennett)
R > 1 Sorption (or retardation) = v/vc Zheng & Bennett, Fig. 4.3
= v/vc Zheng & Bennett, Fig. 4.3
Linear Isotherm LEA (Local Equilibrium Assumption) Zheng & Bennett, Fig. 4.2
Linear Isotherm from MT3DMS manual
Simple form of the ADE Retardation Factor Uniform 1D flow; longitudinal dispersion; sink/source term; retardation
= vc Simple form of the ADE R = v/vc
Freundlich Isotherms Linear Isotherm Unlimited sorption sites Zheng & Bennett, Fig. 4.2
Langmuir Isotherm = maximum sorption capacity Limited sorption sites
fraction of organic carbon Spitz and Moreno (1996)
General form of the ADE: Chemical sink/source term
linear Zheng & Bennett
We will consider two types of chemical reactions • Sorption (adsorption & absorption) • 1st order irreversible reactions (radioactive decay, • hydrolysis, some forms of biodegradation)
Simple form of the ADE 1st order rate constant = ln 2 / half life = 0.693/ t½ Uniform 1D flow; longitudinal dispersion; sink/source term; retardation; 1st order irreversible reaction ( is the same for the dissolved phase and the sorbed phase)