Abstract
In this study, the characteristics of solubilization of sewage sludge (primary sludge+excess sludge) from wastewater treatment plant by subcritical water oxidation process were investigated. The process was found to enhance the solubilization considerably. The solubilization rate of sludge, indexed as the reduction rate of MLSS, ncreased considerably after the treatment (just below 250°C). More than 95% of phosphorus can be recovered by MAP (Magnesium Ammonium Phosphate) method from the treated sludge by subcritical water oxidation process (more than 200°C). It was also observed that effective volume reduction was achieved when the treated temperature was 200°C. As these results, it was shown that the optimum temperature range of this process was between 200°C and 250°C. These results also demonstrate the applicability of subcritical water oxidation process as an attractive novel process of sewage sludge solubilization.
