WHAM - A CHEMICAL-EQUILIBRIUM MODEL AND COMPUTER CODE FOR WATERS, SEDIMENTS, AND SOILS INCORPORATING A DISCRETE SITE ELECTROSTATIC MODEL OFION-BINDING BY HUMIC SUBSTANCES
E. Tipping, WHAM - A CHEMICAL-EQUILIBRIUM MODEL AND COMPUTER CODE FOR WATERS, SEDIMENTS, AND SOILS INCORPORATING A DISCRETE SITE ELECTROSTATIC MODEL OFION-BINDING BY HUMIC SUBSTANCES, Computers & geosciences, 20(6), 1994, pp. 973-1023
WHAM (Windermere Humic Aqueous Model) is designed to calculate equilib
rium chemical speciation in surface and ground waters, sediments, and
soils. The model is suitable especially for problems where the chemica
l speciation is dominated by organic matter (humic substances). WHAM c
ombines Humic Ion-Binding Model V with a simple inorganic speciation c
ode for aqueous solutions. Precipitation of aluminum and iron oxides,
cation-exchange on an idealized clay mineral, and adsorption-desorptio
n reactions of fulvic acid also are taken into account. The importance
of ion accumulation in the diffuse layers surrounding the humic molec
ules is emphasized. Model calculations are performed with a BASIC comp
uter code running on a Personal Computer.