Electrochemical oxidation of industrial wastewater with the tube type electrolysis module system

Electrochemical oxidation effects of the tube type electrolysis module system were investigated for the treatment of industrial wastewater. The tube type electrolysis module consisted of a rod anode and an outer tube cathode. Materials used for the anode were titanium electroplated with RuO2 and IrO2 respectively. Stainless steel was used for the cathode. Chlorate production was one of major factors in electrochemical oxidation of tube type electrolysis module system used in this research. Chlorine conversion from chloride to chlorate occurred at a rate of 66.8 mg/L for the textile wastewater and 75.7 mg/L for the pharmaceutical wastewater over a 60 min retention period. Chlorine gas concentration was 360 ppm for the textile wastewater and 500 ppm for the pharmaceutical wastewater after a 60 min electrolysis period. Specific energy consumption was measured during the electrolytic process with the Ti/RuO2 anode and the Ti/IrO2 anode. The range of specific energy consumption was 0.064–0.108 kW h/gCODCr for the Ti/RuO2 anode over the variation range of hydraulic retention time. The Ti/RuO2 anode had advantages in the electrolytic wastewater treatment with lower specific energy consumption.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The tube type electrolysis module consisted of a rod anode and a tube cathode. ► The recirculation in electrolysis showed positive effects in pollutant removal. ► Chlorine conversion from chloride to chlorate occurred in the electrolytic process. ► Chlorate production was a major factor in the electrochemical oxidation. ► The Ti/RuO2 anode had an advantage of lower specific energy consumption.