Influence of Various Electrode Materials in Electrocoagulation Efficiency: Application in Treatment of Sugar Industry Effluent

Abstract

Sugar industries generate highly polluted effluent in terms of organics and inorganics load and it is very difficult to treat. In the present study, attempts have been made to use electrocoagulation process to treat the effluent. The treatment was carried out using different electrode materials in different combinations. The influence of pH, current density (CD) and treatment time (t_R) on COD removal of sugar industry effluent (SIE) was evaluated. Apart from this, electrode loss, species energy consumption and cost analysis were also carried out. For all electrode materials, pH 7 was found to be optimum, and CD in range of 69.44–104.165 A/m² provided good treatment of the effluent. The performance of Al–MS electrode combination was seen to be the best, as it reduced initial COD of SIE = 4800 mg/dm³ to 920 mg/dm³ (80.83% COD reduction) in 100 min, with treatment cost INR 326 (USD 4.90)/m³ SIE. Kinetics studies showed COD reduction rate to 1.5 order with respect to COD and 0.57 order with respect to CD. The reaction rate constant lies in between 5.0 and 7.1 $\left( {\frac{{{\text{dm}}^{3} }}{\text{mg}}} \right)^{0.5 } \left( {\frac{{{\text{m}}^{2} }}{\text{A}}} \right)^{0.57} \,\min^{ - 1}$.