Abstract

The use of the combine systems consist of pre treatment unit and biological treatment unit is proposed at the treatment of organic pollutants which are can not be removed in conventional biological treatment plants or be created toxic/inhibitor effect to this systems. Pre treatment is the processes based on chemical, physicochemical, enzymatic and thermal oxidation. In pre treatment process, a partial oxidation of pollutants is aimed due to be high operating cost; the complete oxidation is realized in the biological treatment unit. In this paper, studys which focused on the biodegradability improvement and the toxicity reduce of pre treatment in the industrial wastewater treatment and the sludge treatment was given. It was defined that pre treatment processes were efficiency in both the biodegradability improvement and the toxicity reduce. But some researchers were shown that the intermediates originated by mean of pre treatment or the chemical matters used in process may be increaed toxicity. On account of this, to perform the toxicity tests by the side of the biodegradability tests is important in pre treatment step.