Nutrient Removal through Electrocoagulation

Abstract

Several biological processes are having one major limitation for inefficient nutrient removal despite of type of nutrient like phosphate or nitrogen. Further large uses of fertilizer add on the concentration of nutrient in underground water as well in direct runoff which ultimately contributes to surface water. Recently anaerobic biological treatments are gaining wide interest by young researchers and hence understanding limitations of such treatment is necessary and research towards minimization of these limitations is also needed. Upflow anaerobic sludge blanket is one of the anaerobic treatments. In India there are more than 25 STP based on upflow anaerobic sludge blanket reactor. UASB reactor hardly alters nutrient level of effluent being treated. On the other hand electrocoagulation treatment promises good removal of pollutants. Hence simulated phosphate wastewater treatment was carried to understand nutrient removal possibility from anaerobically treated wastewater. Current density, electrolysis time, waste strength, NaCl dose, initial pH, interelectrode distance are various process variables which affect EC efficiency. This study reports effect of electrocoagulation process variables on phosphate wastewater. In this study effect of current density, electrolysis time and waste strength were studied using response surface methodology (RSM) as a statistical tool for design of experiments and statistical data analysis. RSM was done using Design Expert software version 8.0. It is reported through RSM studied that the variation in applied current, exposure time and phosphate concentration has direct effect on EC process efficiency.