Industrial park wastewater deeply treated and reused by a novel electrochemical oxidation reactor

• A novel electrooxidation reactor for effluent treatment from industrial park sewage plant was described in this paper.
• The electro-oxidation technique could decompose residual pollutants in effluent completely and efficiently.
• The treated effluent met the reuse water standards with a lower operating energy consumption.
• This electrooxidation technique was beneficial for wastewater reuse.

Effluent from industrial park sewage treatment plants contains residual contaminants that are mostly composed of non-degradable substances, which results in pollution of local aquatic systems. In this study, a novel electro-oxidation reactor for industrial park wastewater treatment was developed and described. The developed reactor was based on plug flow through meshed plate electrodes composed of titanium (Ti) as cathodes and Ti/PbO2 as anodes. The system could decompose residual pollutants completely and efficiently. Under the optimal operating conditions of neutral pH, a flow cross-velocity of 0.75 m h−1, a current density of 5.0 mA cm−2, and a surface-to-volume ratio of 0.25 m2 m−3, the chemical oxygen demand (COD) and color of wastewater from an industrial park sewage treatment plant decreased to below 60.0 mg L−1 and 20 Hazen, respectively, after 30 min of electrolysis. Additionally, the microbial content decreased from 7 × 104 CFU mL−1 to 0 CFU mL−1 during electro-oxidation, the COD current efficiency was 16.55%, and the energy consumption for 1 ton of effluent was 4.12 kWh. The operating cost for effluent was $0.57 per ton according to the local electricity price of $0.14 kWh−1 for industries. The effluent quality after deep treatment met the needs of recycling water quality and could be reused for miscellaneous water consumption and scenic purposes, resulting in reduced use of water resources and pollution.