Sludge Reduction through Ozonation: Effects of Different Specific Dosages and Operative Management Aspects in a Full-Scale Study

Abstract

The activated sludge process constitutes the most widely used wastewater treatment. The main drawback of this biological technology, however, is the excess sludge produced (ESP). In fact, disposal and management of this waste is one of the most expensive management costs at wastewater treatment plants (WWTP). Cell lysis based on the lower net biomass growth under cryptic conditions is one way to minimize the ESP directly in the water line. Ozone is a powerful oxidant used for this purpose. This paper reports the long-term data obtained at a full-scale plant (50,000 PE) where a fraction of the recycled sludge is treated with a low specific ozone dosage and a high treated sludge rate of approximately