Corrosion Performance of Mild Steel in Paper Mill Effluent

Present paper reports investigations carried on corrosion behaviour of mild steel in effluents collected from paper mill treatment plant. For this purpose, effluent was collected from after primary and secondary treatment stages. Mild steel samples were exposed to these effluents for duration of six months. The corroded samples were analysed for weight loss and extent of localised corrosion. Electrochemical polarization tests like open circuit potential (OCP), tafel plot and anodic polarization were also performed to estimate corrosion rate, polarization resistance and localized corrosion parameters in the studied system. The extent of corrosion attack has been correlated with effluent parameters namely pH, electrical conductivity (Ec), total suspended solids, total dissolved solids, chemical oxygen demand, biochemical oxygen demand, chloride content, colour and sulphate.