Treatment of Textile Wastewater Using Advanced Oxidation Processes-A Critical Review

Textile manufacturing is a multi-stage operation process that produces significant amounts of highly toxic wastewater. Given the size of the global textile market and its environmental impact, the development of effective, economical, and easy-to handle alternative treatment technologies for textile wastewater is of significant interest. Based on the analysis of peer-reviewed publications over the last two decades, this paper provides a comprehensive review of advanced oxidation processes (AOPs) on textile wastewater treatment, including their performances, mechanisms, advantages, disadvantages, influencing factors, and electrical energy per order (E-EO) requirements. Fenton-based AOPs show the lowest median E-EO value of 0.98 kWh m(-3) order(-1), followed by photochemical (3.20 kWh m(-3) order(-1)), ozonation (3.34 kWh m(-3) order(-1)), electrochemical (29.5 kWh m(-3) order(-1)), photocatalysis (91 kWh m(-3) order(-1)), and ultrasound (971.45 kWh m(-3) order(-1)). The Fenton process can treat textile effluent at the lowest possible cost due to the minimal energy input and low reagent cost, while Ultrasound-based AOPs show the lowest electrical efficiency due to the high energy consumption. Further, to explore the applicability of these methods, available results from a full-scale implementation of the enhanced Fenton technology at a textile mill wastewater treatment plant (WWTP) are discussed. The WWTP operates at an estimated cost of CNY yen 1.62 m(-3) (USD $0.23 m(-3)) with effluent meeting the China Grade I-A pollutant discharge standard for municipal WWTPs, indicating that the enhanced Fenton technology is efficient and cost-effective in industrial treatment for textile effluent.