In this paper an artificial neural network is developed to model a new depo
llution process that uses sequential cultures of anaerobic bacteria and yea
sts to efficiently remove both carbon and nitrogen from wastewaters. A set
of batch experimental runs are used to train and test various neural networ
k topologies. It is shown that the neural network accurately tracks the dyn
amics of the biological species of the yeast reactor in the process and acc
ount for the influence of butyric acid, ammonia and pH on the overall effic
iency of purification.