Effectiveness of Coagulation Process in Removing Reactive Blue 19 Dye from Textile Industry Wastewater

In this research, coagulation process efficiency using three coagulants poly aluminum chloride (PACl), alum and ferric chloride in the presence of coagulants aid anionic polyelectrolyte and kaolin were studied for removal of synthetic wastewater containing reactive blue 19 dye in lab scale. The effect of main parameters such as pH, coagulant concentration, initial dye concentration and presence of coagulants aid has been investigation. The results showed that the best efficiency for dye removal using three coagulants was acheived in neutral pH. Under this condition optimum concentrations of poly aluminum chloride, alum and ferric chloride was 200mg/L, 300mg/L and 400mg/L and their related removal efficiency was 91%, 92% and 81% respectively. Addition of polyelectrolyte as a coagulant aid with ferric chloride slightly increased process efficiency, whereas adding polyelectrolyte with alum and poly aluminum chloride slightly decreased efficiency. Adding kaolin as a coagulant aid with PACl increased process efficiency about 5%, whereas adding kaolin with alum slightly decreased process efficiency and can be ignored also, in the case of ferric chloride no significant effect on process efficiency observed in the presence of kaolin. Finally regarding above mentioned results, coagulation can be a robust alternative method for the treatment of reactive dye containing wastewaters.