“…The widely accepted model for aerobic processes, Monod's model (Monod, 1949) however, could not be employed to describe the relationships between the substrate utilization and the biological growth. The aerobic treatment of the distillery wastewaters of different origins showed that all these experimental findings could be very well correlated with the Contois model (Beltran et al, 2001, Beltran et al, 1999. According to the Contois model, the relationship between the specific substrate based growth rate of microorganisms (m) and the substrate concentration in a batch process, limited by the amount of the available substrate and can be expressed as:…”