Abstract: A process is disclosed for regulating the aeration in a biological wastewater treatment plant using a carbon removal stage, a nitrification stage and a denitrification stage. The process includes the step of continuously measuring the value of oxidation-reduction potential of the treated medium as well as measuring oxygen concentration of the treated medium during aeration phases. This permits maintaining aeration if the oxygen concentration falls within a preselected reference range. Alternately there is reduction of the aeration if the oxygen concentration is above the preselected reference range, or increasing the aeration if the oxygen concentration falls below the preselected reference range.

Abstract: The oxidoreduction potential is measured on each of a number of tanks. A data processing system analyzes the oxidoreduction potential evolution and establishes a diagnosis of the aeration/biology couple to ensure the degradation reactions of the carbonaceous and nitrogenous pollution. It is then determined whether to start, to continue, or to stop aeration in the tanks, depending on the required degree of purification. In the first tanks, priority is given to the treatment of carbonaceous pollution with specific parameter representation of the oxidoreduction potential threshold values. In the last tank, fine-tuning the treatment of the carbonaceous and nitrogenous pollution is accomplished by managing the aeration.

Abstract: A method of regulating aeration in biological treatment of wastewater by implementing a step of eliminating carbon in aerobiosis, a step of nitrification in aerobiosis, and a step of denitrification in an anoxia, in which method the oxidation-reduction potential is continuously measured in a treatment system, a curve is established of variation in oxidation-reduction potential as a function of time, and the derivative thereof is calculated, wherein, when the derivative tends towards zero, the derivative and the value of the oxidation-reduction potential are correlated to determine whether aeration should be started, continued, or stopped.