Application of Ozone on Activated Sludge: Micropollutant Removal and Sludge Quality

摘要

This study focuses on the reaction of ozone with constituents of activated sludge liquor with the aim of understanding the behavior of organic micropollutants and to analyze the changes in the mixed liquor sludge matrix. To do so, different sludge sampling campaigns from two different wastewater treatment plants (WWTPs) were treated with different transferred ozone doses (TOD) and analyzed observing the effect on the sludge properties and micropollutants removal. Indeed, the ozone treatment promotes changes in the sludge matrix, increasing the Chemical Oxygen Demand (COD) solubilization until the Immediate Ozone Demand (IOD) completion and decreasing the Sludge Volume Index (SVI). Moreover, significant pharmaceutical removals have been achieved with low transferred ozone doses (TODs), reaching removals up to 99 depending on the compound.