Integrated process combined with fenton reaction for the treatment of papermaking deinking wastewater

Abstract

The pulp and paper industry employs processes that produce a large amount of wastewater, resulting in pollution of the environment. In the present study, deinking wastewater was treated using an integrated process of combined coagulation/flocculation, activated sludge process, and Fenton reaction system. The deinking wastewater produced from a large-scale papermaking company was treated. Results indicated that the sedimentation with coagulation and flocculation, used as a pretreatment process, was a preferred option for SS removal. The semi-extended aeration system for COD and BOD5 removal delivered excellent performance. The residual and barely biodegradable pollutants in the wastewater could be efficiently removed by Fenton reactions. The COD, BOD5, and SS total removal efficiencies achieved were 94%, 90%, and 99%, respectively. Measures for control proposed in the present study can efficiently resolve the problems encountered in the operation and can maintain a stable process. The integrated process combining coagulation/flocculation, activated sludge process, and the Fenton reaction system is a favorable option for the long-term operation of the treatment of deinking wastewater. Fenton reactions as a tertiary process applied in deinking wastewater treatment can remove efficiently recalcitrant pollutants and show reliable performance for effluent.