The objective of this paper was to present an integrated modeling appr
oach to biokinetics and stoichiometry of anaerobic treatment processes
. A software system has been developed to calculate bacterial yield co
efficients from stoichiometry under different anaerobic bioprocess con
ditions. Kinetic constants, i.e., the reaction rate constant and Monod
half-velocity coefficient, were determined from batch experimental da
ta using Conreg, a software system for constrained nonlinear regressio
n. Additional experiments were performed to evaluate the usefulness of
the Inhibition Coefficient model to predict toxicity of ammonia and m
ethylene chloride in anaerobic batch systems. The integrated approach
to biokinetics and stoichiometry and the software developed for this p
urpose should help engineers quickly evaluate a wide variety of design
options for anaerobic treatment systems under both toxic and non-toxi
c conditions. Other useful applications include prediction of natural
rates of methane (a gas causing global warming) formation in rice padd
ies.