Treatment of paper recycling wastewater using microwave technology

Abstract

In this study, we conducted a novel method by using a household type Microwave Owen (MW) under selected operational parameters (power and time) to treat wastewater from paper recycling under laboratory conditions. We seek to evaluate changes of the MW experimental parameters, comparatively. All measured pH values were found to be in very narrow range, between pH 7.10 (BII) and pH 7.53 (DIV), in slightly alkaline range (>7.0). However, the highest Electrical Conductivity (EC) difference was found to be 46 µS/cm. The 60 seconds MW irradiated samples at four power levels (90-, 180-, 270-, 360 Watts) showed higher ORP values than control (C1: 195 mV) while the highest ORP value of 213 mV was found with sample treated 360 W and 60 seconds (DIV). It is notable that sample DIV showed the highest pH, EC, ORP and TDS value. The control sample had turbidity value of 42.5 NTU. In all MW power levels and durations, turbidity removal was apparent which MW impact on turbidity. The lowest turbidity value of 22.2 NTU was found with sample DIV which was the highest rate of turbidity removal efficiency (DIV: 86.2%). The present study revealed that MW irradiation could be used to effectively reduce the selected physicochemical parameters that may assist in the description of wastewater quality.