Treatment of Textile Wastewater Containing Basic Dyes by Electrocoagulation Process

Document Type : Research Paper

Authors

1 Graduate Student of Applied Chemistry, Tabriz University

2 Professor of Applied Chemistry, Tabriz University

Abstract

Textile wastewaters from dying and finishing processes in the textile industry have been a serious environmental problem for years. Electrocoagulation (EC) as an electrochemical method was developed to overcome the drawbacks of conventional textile wastewater treatment technologies. EC technique uses a direct current source between metal electrodes immersed in polluted water. The electrical current causes the dissolution of metal plates including iron or aluminum into wastewater. The metal ions can form wide ranges of coagulated species and metal hydroxides that destabilize and aggregate the suspended particles or precipitate and adsorb dissolved contaminants. This paper studies the treatment of wastewater at Nagshejahan textile factory in Tabriz containing basic dyes by electrocoagulation using iron electrode in batch electrochemical cell and the effect of operational parameters such as current density and time duration of electrolysis. In addition, electrical energy consumption and current efficiency were also studied. To evaluate the efficiency of this method for treating  the mentioned wastewater, color and COD reduction were measured after each treatment. The results showed that applying optimum current densities of 80-100 Am-2 and electrolysis time of 8 minutes for 250 mL of the wastewater, the color and COD reduced around 94% and 82%, respectively. Also, in the above mentioned conditions, the electrical energy consumption and Current efficiency were figured at about 1.2 kWh/m3 and 103%, respectively.

Keywords


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