Removal of Aquatic Humus by Ozonation and Activated-Carbon Adsorption

The separate and combined effects of treatment with ozone and activated carbon were studied for three different humus sources: Norwegian brook water, Norwegian bog water, and commercial humic acid. The effect of ozonation on solution properties was determined by ultrafiltration, color, UV, and dissolved organic carbon (DOC) analysis. Adsorption prior to and after ozonation was studied in laboratory isotherm studies and a pilot-scale column experiment. Ozonation caused significant reductions in the content of high-molecular-weight material, UV extinction, and color; DOC reductions were insignificant for ≤1 mg of ozone per mg of DOC. Both isotherm and pilot-scale studies showed significant increases in adsorption capacities resulting from preozonation.