Abstract
The solar photo-Fenton process, which is one of the advanced oxidation processes, offers a promising technology for minimization of excess sludge. This study assessed the effect of solar photo-Fenton treatment of waste activated sludge (WAS). The operating parameters, viz. pH, ferrous iron concentration and hydrogen per oxide were optimized as 3, 40 mg/L and 4 g/L. SCOD and TCOD were 380 mg/L and 1,700 mg/L at 4-h contact time. The effects of the three critical factors, viz. pH, ferrous iron concentration and hydrogen peroxide for pretreatment of WAS were simulated and evaluated using response surface methodology. This methodology has shown to be a valuable tool to model complex process such as the light-enhanced photo-Fenton reaction and to achieve optimum experimental parameters at minimal cost. Solar photo-Fenton process achieved 4.62% COD solubilization at 4-h contact time.