Evaluation of Turbidity and Color Removal in Treatment of Wastewater Containing Resistant Pollutants with Ozonation

In this research a comparison in turbidity and color removal between biological treatment of industrial wastewater and a combination of that with ozonation is studied. Wastewater arising from pulp factories has toxic and resistant pollutants which cause some serious environmental problems and its color and turbidity must be considered to meet the standards (Metcalf et al., 2004). Because of high molecular weight of these toxic compounds the treatment is performed in a sequential process in order to make these compounds smaller and change them to dissolvable substances in the environment. Although with bio-ozone-bio treatment the value of consumed ozone is considerably increased, but through this way the quality of treatment and the value of dissolvable substances which can be returned to the environment are increased. A very remarkable reduction of color and turbidity in this treatment system in comparison with the most common biological treatment systems in pulp factories is achieved.