Electrocoagulation for the Treatment of Metals Machining Plants Effluents: Experimental and Modeling Study

Treatment of effluents discharged from mechanical machining of copper and copper alloys for removal of cutting oils and toxic copper ions by electrocoagulation was studied using a cell containing two steel electrodes and a built-in heat transfer facility. Current density, initial pH of the solution, temperature, starting pollutants' concentrations, amount of NaCl supportive electrolyte, and the impact of gas sparging were investigated. Response surface methodology was used to correlate % oil removal, % copper removal, and electrical energy consumption to the affecting variables. The results imply that the cubic model fits well with the experimental results. The electrocoagulation of oil and copper from waste solutions was optimized using the response optimizer. The simultaneous removal of oil and Cu2+ in the same cell could lower the operational and capital expenses of wastewater treatment.