Recovery and Recycle of Water from Dye Effluent by Partial Crystallization at Sub-Ambient Temperature

Abstract

Experiments were conducted for recovery of water from real dye effluents. The dye effluent was collected from an industry at Namakkal, Tamilnadu, India. The effluent was diluted with water to various concentrations. All the dye solutions were subjected to freeze concentration in freezer until one third of the dye solution was converted to solid phase. The concentration of solid phase and liquid phase so formed by partial freezing were compared with that of the dye solution before freezing. It was observed that the solid and liquid phases had different concentration of dye. The concentration between solid and liquid phase was found to increase with increase in concentration of the original dye effluent. After partial freezing, the concentration of the dye effluent was higher in the solid phase that in the liquid phase. The results of the study showed that freeze concentration for the recovery and reuse of waste water from dye effluents will be a good alternative to many old techniques and also environmental friendly.