Assessment of remediative potential of metals from electroremediated sewage sludge

Sewage sludge is a by-product that arises as a secondary waste from sewage treatment plants. It can alter soil and water’s properties and interfere with the food chain when these are not disposed off. These wastes are often rich in metals like which cannot be degraded easily. For the removal of heavy metals in sewage sludge, there are several methods, out of which electroremediation is a cost-effective and efficient technique. In the present study, electroremediation has been carried out without the addition of any chelating agents and subjected to low voltage for a period of eleven days. Two sets of sewage sludge termed as control and treated to assess the difference after the treatment. Samples were collected on alternate days at cathode and anode ends. Physicochemical and heavy metals analysis were conducted for the treated and control sets. In the treated set, reduction has been observed in Pb, Mn, V, Al, Ti and Cr. Cu, Ni and Zn at cathode and anode ends. The reduction in metal concentrations at anode and cathode has been observed due to the prevailing acidic conditions all over the medium except in the case of S. Statistical analysis for the current study has been performed and found that all the parameters after treatment showed a significant difference in the concentration of heavy metals in sewage sludge in comparison with control. Thus, from the results, it is evident that electroremediation can be applied as a feasible technique for treating heavy metals in sewage sludge.