Study of the efficiency of polyelectrolytes in the treatment of liquid effluents resulting from hot-dip galvanizing

In this study, the treatment of liquid effluents from industry hot-dip galvanizing was made by the process coagulation/flocculation. The optimization of this process has shown that the physical-chemical and biological parameters indicating the degree of pollution have been recorded in the following abatement rates: (72.85%) for conductivity, (98.80%) for turbidity, (97%) for suspended solids, (98.88%) for the chemical oxygen demand and (98.96% for the biochemical oxygen demand in the case of treatment with the couple lime/PVAs. However those obtained during the treatment with the couple lime/PVAc we obtained only a removal: (67.76%) of conductivity, (98%) of turbidity, (96%) of suspended solids, (98.28%) of the chemical oxygen demand, (98.68%) of the biochemical oxygen demand. According to the results obtained by this study, we have shown that the treatment of residual waters by the coagulation/flocculation process is more efficient when using the lime/PVAs compared to the lime/PVAc and with respect to the reference method employ company level hot dip galvanizing.