CONTROLLING METHOD FOR BIOLOGICAL DENITRIFICATION

摘要

PURPOSE:To provide a controlling method for biological denitrification which is applicable to sewage disposal, living drainage disposal, and the other wide applications without necessitating homogenizing by storage of influent. CONSTITUTION:At least two indexes selected from among DO (dissolved oxygen demand) in a biological reaction tank 10, ORP (oxidation-reduction potential), pH and ammoniac nitrogen or oxidizable nitrogen are detected by a sensor 12. The same detected thereby are inputted into a fuzzy controller 1 and the optimum feed rate of air is successively judged by fuzzy inference and output. Thereby the amount of aerating air of an aeration blower 13 is controlled. The amount of returned sludge and/or the length of nitration time are simultaneously judged in addition to the above-mentioned optimum feed rate of air. Biological denitrification may be controlled by a plurality of outputs.