Formation of transformation products during ozonation of secondary wastewater effluent and their fate in post-treatment: From laboratory- to full-scale

Ozonation is increasingly applied in water and wastewater treatment for the abatement of micropollutants (MPs). However, transformation products formed during ozonation (OTPs) their fate biological or sorptive post-treatments largely unknown. In this project, a high-throughput approach, combining laboratory experiments detection by liquid chromatography high-resolution mass spectrometry (LC-HR-MS/MS), was developed to identify OTPs effluent large number relevant MPs (total 87). For experiments, simplified experimental solution, consisting surrogate organic matter (methanol acetate), created, which produced conditions similar realistic terms ozone hydroxyl radical exposures. The 87 selected parent were divided into 19 mixtures, enabled identification with an optimized experiments. following two approaches considered OTPs. (1) A screening LC-HR-MS signal formation these performed revealed list 1749 potential OTP candidate signals associated 70 MPs. This can be used future suspect studies. (2) that both batch samples plants (WWTPs). second approach ultimately more time-efficient four different WWTPs (specific doses range 0.23-0.55 gO3/gDOC), leading 84 40 effluent. Chemical structures could proposed 83 through interpretation MS/MS spectra expert knowledge chemistry. Forty-eight (58%) have not been reported previously. verified studied post-treatment steps. During sand filtration, 87-89% stable. granular activated carbon (GAC) filters, abated decreasing efficiency increasing run times filters. example, GAC filter 16,000 bed volumes, 53% abated, while 35,000 40% abated. highest (87% OTPs) observed when 13 mg/L powdered (PAC) dosed onto filter.