Farid Yousefi - Department of Civil Engineering, Sharif University of Technology, Tehran, Iran
Mohammad Raie - assistant professor of the Water and Environmental Engineering group Department of Civil Engineering, Sharif University of Technology, Tehran, Iran

Pulp and paper industries are ranked sixth among the world's most hazardous industries. The mostcritical pollutant in these effluents is high COD. It is essential to treat this wastewater before itenters the environment since it causes environmental problems if it enters the receiving waters. Thequality of pulp from cardboard waste depends on how well it is separated at the source; therefore,the quality of the wastewater contaminants differs across different countries. We conducted thisstudy for pulp and paper wastewater treatment in Iran. This study used poly aluminum chloride andalum as coagulants and cationic and anionic polymers as flocculants at different pHs. Thewastewater used was real wastewater with an initial COD and turbidity of ۴۳۵۰±۳۰ ppm and ۸۰±۵NTU. The parameters of COD, turbidity and sludge volume index were evaluated as comparisoncriteria. It was observed that the use of ۷۵۰-۱۲۵۰ ppm Alum as a coagulant and cationic flocculantat the pH of ۷.۸ is the best choice for pulp and paper wastewater treatment. It is suggested thatfuture research will focus on the biological treatment of pulp and paper mill wastewater in Iran.

Pulp and Paper Mill, Wastewater Treatment, Chemical Treatment,C oagulation andFlocculation