Introduction to BEM (Batch Equilibrium Model)

Göttingen

1991

51 S.

Bandaufführung

102371

BEM is a computer program for the calculation of coupled chemical equilibria in aqueous electrolyte systems. The equilibria may include complexation, acid/base reactions, dissolution/precipitation of salts and cation exchange. Changing total concentrations in consecutive batch experiments can be modelled. Several such models may be linked to give a rough representation of transport processes (batch cascade). The concepts of BEM are introduced and the equations on which the program is based are documented completely. Particular models are specified to BEM via files. These files are readable, concise definitions of models. The elements of these files are explained. Two examples are presented. The first is a titration of aluminum ions with hydroxide in the presence of a complexing ligand. The second is an acidification model for "topsoil", "subsoil" and "creek" in a watershed.