JAGDEESH KUMAR1 HIMANSHU JOSHI2
1. Research Scholar, Department of Hydrology, Indian Institute of Technology Roorkee, Uttarakhand state, 247667, India
2. Professor, Department of Hydrology, Indian Institute of Technology Roorkee, Uttarakhand State, 247667, India
Discharge of metallic waste stream from industrial processes is a considerable concern for the environment. In the present industrial era, various industries (mining, metal plating, paints, pigments, tanneries, metal processing etc.) generate a sizeable volume of wastewater. The heavy metals present in these wastewaters are non-biodegradable, persistent, highly toxic and tend to bioaccumulate into the body tissues. Nanofiltration (NF) and Electrocoagulation (EC) processes, which present an advancement over the conventional treatment processes, efficiently separate the charged metal ions from the industrial wastewater. In the present study,
response surface methodology (RSM) was employed to develop a model for the optimization of NF and EC processes. The impact of variables pH, feed concentration, pressure and temperature were investigated for NF process and reaction time, pH, solution concentration and current for EC process, respectively, in the removal of heavy metals (Cu, Ni, Zn) and water recovery. The experiments were planned using a central composite design through RSM, and the model results were statistically analyzed using analysis of variance (ANOVA). The rejection efficiency of Zn, Ni and Cu through NF membrane was observed as 98.64%, 90.54% and 99.99%, respectively, while the removal of these through the EC process was 99.81%, 99.99% and 99.98%, respectively. Based on the experimental findings, it could be concluded that both the NF and EC processes are significantly efficient for the removal of the studied metals in a mixed metal stream.