Study on Degradation of Printing and Dyeing Wastewater by Electrochemical Treatment

Abstract

Due to the large amount of complex organics and its low biodegradability, the degradation of printing and dyeing wastewater attracts lots of attention. In this paper, the actual printing and dyeing wastewater was treated by electrochemical method, and the effects of pH, electrolyte concentration, anode electrode, two-dimensional electrolysis, three-dimensional electrolysis, combined processes were discussed. In the combined process case, the electrochemical process as a pretreatment or advanced treatment was explored.. The research showed that the optimal pH value was 3 by two-dimensional electrolysis, while the value was 9by three-dimensional electrolysis. The COD removal rate is 85.4% (three-dimensional) and46.6% (twodimensional). The order of treatment effects of different electrode is as following: SS/PbO2>Ti/PbO2>Ti/RuO2-La2O3> without electrode plates. The degradation effects of electrolysis, iron-carbon, and Fenton individually are not as good as the combination process, and the electrochemical process is more suitable on the front of iron-carbon process or Fenton process.