Effects of Ozonation on AOC Content of Humic Finnish Groundwater

The effects of ozonation on assimilable organic carbon (AOC) content of humic groundwater were investigated in batch experiments on three different groundwaters used as drinking water in Finland. All water samples had quite high concentrations of iron (range 2–10 mg/L) and manganese (range 0.1–0.2 mg/L) and therefore combined ozonation and filtration is a possible water purification method. The ozone dosage used varied from 0 to 16.6 mgO3/L (ΔO3/TOC = 0–1.6). The ozone treatment increased the AOC concentration in the groundwater samples to different degrees. For example, an ozone dose of 3.9 mg/L increased the AOC concentration in different water as follows: from 49 μg/L to 55/L, from 7 μg/L to 119 μg/L and from 23 μg/L to 226 μg/L.