Abstract: A rotary disc filter is provided with an integrated backwash and chemical cleaning system. In one mode of operation, backwash is directed through a control valve to one or more nozzles for spraying the backwash onto the filter media forming a part of a rotary disc filter. In a second mode, a chemical cleaning mode, the pump directs backwash through an eductor that induces a chemical into the inductor which is mixed with the backwash to form a backwash-chemical mixture that is sprayed onto the filter media. A control system is used in conjunction with the backwash and cleaning systems to monitor process information and/or filter media properties and to determine when to perform backwashes and regenerative cleanings in order to optimize the performance of the filter system.

Abstract: A wastewater treatment system is provided that includes first and second reactors, each operative to nitrify or denitrify wastewater contained therein. Downstream from the first and second reactors is a membrane reactor that operates under aerobic conditions and includes one or more submersed membranes for separating solids. Extending between the membrane reactor and each of the first and second reactors is a return activated sludge line with appropriate controls for permitting return activated sludge to be directed to one of the reactors at a time. To nitrify and denitrify wastewater, a wastewater influent stream is alternatively directed to the anoxic reactors which are alternatively operated under aerobic and anoxic conditions so as to nitrify or denitrify the wastewater contained therein.