Removal of pharmaceuticals with ozone at 10 Swedish wastewater treatment plants

Pilot-scale tests were run with ozonation for reduction of 24 pharmaceuticals at 10 full-scale wastewater treatment plants in southern Sweden. Reduction was evaluated based on doses of 3, 5 and 7 g O-3/m(3) at all plants. The reduction of pharmaceuticals reached on average 65% at 3 g O-3/m(3), 78% at 5 g O-3/m(3) and 88% for 7 g O-3/m(3) in terms of total concentration of pharmaceuticals. Specific ozone dose (ratio O-3: TOC) was found to be highly influential on pharmaceutical removal. At two WWTPs, the pharmaceutical removal was severely reduced.