Treatment of explosive-contaminated wastewater through the Fenton process

Abstract

Owing to the extremely high chemical oxygen demand (COD), toxicity, and acidity of the explosive-contaminated wastewater, biological processes cannot be directly applied for its treatment. Therefore, Fenton’s reagent was employed to treat the explosive wastewater before discharge. The Fenton process is also the easiest and most reliable method of advanced oxidation. The treatment of this wastewater with pH, COD, acetate, nitrate, and sulfate contents of 2.32, 200 g L⁻¹, 160 g L⁻¹, 40 g L⁻¹, and 35 g L⁻¹, respectively, was investigated in this study. The effects of the hydrogen peroxide feeding rate, ferrous ion dosage, and hydrogen peroxide dosage on the efficiency of the Fenton process were investigated. The optimal conditions obtained in this study for the treatment of explosive wastewater were 358 mM of Fe²⁺ and continuous feeding of hydrogen peroxide (0.33 mL min⁻¹), without pH adjustment or temperature control. The highest COD removal efficiency was 70% with an oxidation efficiency (OE) of 75% in 3 h. The addition of hydrogen peroxide had no impact on the observed COD conversion.

Keywords:

• Advanced oxidation processes
• Explosive wastewater
• COD
• Fenton
• Oxidation efficiency

Acknowledgements

This research was financially supported by the Ministry of Education (Grant P9823), the National Science Council, Taiwan (Grant NSC 99-2221-E-041-012-MY3) and the National Center of Excellence for Environmental and Hazardous Waste Management, Thailand.