Application of synthetic polyamine flocculants for dye wastewater treatment

Polyamine flocculants were synthesized and applied for the removal of color, turbidity, and organic compounds from dye wastewater. The effect of polyamine on color removal was investigated by comparing 2 treatments: 1) alum alone and 2) alum/polyamine in combination. The effects of polyamine flocculant, concentration, types, and pH on the removal efficiency of colored materials were investigated. Polyamine flocculants were highly efficient in the removal of color and turbidity from dye wastewater. Compared with alum alone treatment, an addition of 25 mg/L of polyamine could reduce alum dosage by more than 50% and improve the color and turbidity removal efficiency. Highly efficient color removal was obtained by adding polyamine as a flocculant at widely different pH ranges. Results indicate that the use of polyamine flocculant is cost effective in dye wastewater treatment because it minimizes the amount of sludge produced as the dosage of inorganic coagulant is highly reduced. Effects of zeta potential and pH are also discussed in the paper.