Advanced Processing of Biologically-Treated Papermaking Wastewater by Poly-Aluminum Chloride (PAC)

In this study, biologically treated paper-making wastewater was treated using PAC to study removal efficiency of color as a function of pH and dosage of PAC. It was found that PAC was relatively effective in removing color from biologically papermaking wastewater. The optimal dosage, pH and stirring time were 40 mL L -1 , 5 and 30 min, respectively. Effluent color after coagulation at the optimal conditions was 40 PCU, meeting requirements of Industrial Wastewater Discharge Standard of Pulping and Papermaking (GB3544-2008) . Therefore, PAC dosage of 40 mL L -1 and pH of 5 were recommended for treatment of biologically treated papermaking wastewater.