| บทคัดย่อ(English) |
The research was conducted to treat tannery wastewater by using two methods of electrochemical techniques including the electroprecipitation in a membrane reactor and the electrocoagulation techniques. The parameters investigated in the both tratement processes were initial pH of wastewater, current density and flow rate of wastewater. The results indicated that the optimum condition for treating tannery wastewater by using the electroprecipitation technique was current density 69.8 A/m('2), flow rate of wastewater 4.5 l/min and initial pH 4.5. At this condition, more than 98% of chromium was removed within 60 min. Beside chromium by using this technique, some organic pollutants were removed as a chromium-organic pollutant compounds. The operating cost related to the electricity cost was approximately 0.86 US$/m('3) wastewater. For the electrocoagulation technique, the optimum condition was found by applying the monopolar electrodes in parallel configurations at current density of 20.67 A/m('2), flow rate of wastewater of 3.67 l/min and 20 min electrolysis time. Atthis condition, more than 90% of pollutants were eliminated from the wastewater and the properties of the treated wastewater was approved to discharge into the regulation environment. The total operating cost of the treatment process was approximately 0.30 US$/m('3) which was lower than that of electroprecipitation technique and activated sludge process of the tannery industry. |
