Integrated Fenton Oxidation Process for Advanced Treatment of Biologically Treated Coking Plant Effluent

Experiments of Fenton oxidation, carbon adsorption, and Fenton oxidation plus carbon adsorption were conducted to develop a cost effective advanced treatment process for treating a biotreated coking plant effluent. Fenton oxidation (Fe²⁺ = 56 mg/L and H₂O₂ = 27.2 mg/L) was effective for removing >50% organic pollutants, measured as UV₂₅₄ (aromatic organics), ViS₃₈₀ (color ingredients) and COD and most total cyanide present in the effluent. Fenton oxidation enhanced adsorptive capacities of activated carbon for the residual contaminants and made them more biodegradable. The Fenton oxidation followed by adsorption and biodegradation in a biological activated carbon (BAC) adsorber is an attractive advanced treatment process to recycle the final effluent for many reuses while meeting the anticipated much more stringent discharge limits of the future.