Eco-industrial processes require high reliability control and supervision methodologies, so as to achieve the best compromise possible between the process' efficiency, safety and economy. Industries often focus on the two first objectives mainly, since they are unwilling to "experiment" not yet validated and/or complex control methodologies if safety and/or efficiency of the process may be jeopardized. This work focuses on an industrial wastewater treatment process, including a cyanides oxidation stage and a neutralization stage, applied to the surface treatment effluents. The project involved the development and validation of a model which enables to simulate various pH-control strategies as well as faults in the CSTRs.