title: Decreased UV absorbance as an indicator of micropollutant removal efficiency in wastewater treated with ozone.
abstract: Ozone transforms various organic compounds that absorb light within the UV and visible spectra. UV absorbance can therefore be used to detect the transformation of chemicals during ozonation. In wastewater, decolourisation can be observed after ozonation. This study investigates the correlation of the UV absorbance difference between the ozonation inlet and outlet and the removal efficiency of micropollutants in wastewater. The absorbance at 254 and 366 nm was measured at the ozonation inlet and outlet, as was the concentration of 24 representative micropollutants and the dissolved organic carbon (DOC). The results clearly showed that the relative decrease of absorbance (ΔAbs) is positively correlated with the relative removal efficiency of micropollutants. We therefore suggest that UV absorbance can be used as a feedback control parameter to achieve optimal ozone dosage in wastewater treatment plants and to gain a fast insight into the process efficiency and stability of the ozonation.
authors: Swiss Federal Institute of Aquatic Science and Technology (Eawag), Überlandstrasse 133, CH-8600 Dübendorf, Switzerland E-mail: hansruedi.siegrist@eawag.ch.
authors: A
authors: A
authors: Wittmer
authors: Swiss Federal Institute of Aquatic Science and Technology (Eawag), Überlandstrasse 133, CH-8600 Dübendorf, Switzerland E-mail: hansruedi.siegrist@eawag.ch.
authors: A
authors: A
authors: Heisele
authors: Swiss Federal Institute of Aquatic Science and Technology (Eawag), Überlandstrasse 133, CH-8600 Dübendorf, Switzerland E-mail: hansruedi.siegrist@eawag.ch.
authors: C S
authors: CS
authors: McArdell
authors: Swiss Federal Institute of Aquatic Science and Technology (Eawag), Überlandstrasse 133, CH-8600 Dübendorf, Switzerland E-mail: hansruedi.siegrist@eawag.ch.
authors: M
authors: M
authors: Böhler
authors: Swiss Federal Institute of Aquatic Science and Technology (Eawag), Überlandstrasse 133, CH-8600 Dübendorf, Switzerland E-mail: hansruedi.siegrist@eawag.ch.
authors: P
authors: P
authors: Longree
authors: Swiss Federal Institute of Aquatic Science and Technology (Eawag), Überlandstrasse 133, CH-8600 Dübendorf, Switzerland E-mail: hansruedi.siegrist@eawag.ch.
authors: H
authors: H
authors: Siegrist
mesh_terms: D010126:Ozone / Q000737:chemistry*; D013557:Switzerland; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
chemical_list: D010126:Ozone; D062065:Wastewater; D014874:Water Pollutants, Chemical