Method for regulating aeration during waste water biological treatment

摘要

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. The process requires comparing the oxygen concentration in the treated medium with the preselected reference range during a transition of the oxidation-reduction potential (partial nitrification/total nitrification); and adjusting the reference range of oxygen concentration to a new set of values to correct the oxygen concentration toward a preselected desired level.