A rational strategy of combining Fenton oxidation and biological processes for efficient nitrogen removal in toxic coking wastewater

• DOI: 10.1016/j.biortech.2022.127897
• Publication Date: 2022-09-06T08:24:22Z
• Authors: Chen Wang; Yaming Liu; Mingjie Huang; Wei Xiang; Zhicheng Wang; Xiaohui Wu; Feixiang Zan; Tao Zhou
• Keywords: Partial nitrification–denitrification; Sewage; Nitrogen; Wastewater; Nitrification; 01 natural sciences; 6. Clean water; Ternary combined process; Bioreactors; Cocaine; 13. Climate action; Fenton oxidation; Denitrification; Biological treatment; Coking wastewater; Coke; Oxidation-Reduction; 0105 earth and related environmental sciences

Effective removal of nitrogen from coking wastewaters is a great challenge, since conventional biological technologies commonly suffer from concentrated bio-toxic components such as phenolic compounds and thiocyanide (SCN-). This study has successfully developed a novel ternary process for efficiently removing nitrogen from a practical coking wastewater, by rationally combined biological pretreatment, Fenton sub-pretreatment and final partial nitrification-denitrification (PN) process. It was noted that the oxic biological pretreatment (OP) could degrade above 80 % of COD and SCN- in the wastewater, by adopting the pristine coking wastewater sludge. Fenton sub-pretreatment would further degrade the residual toxic organics and protect the metabolic activity of nitrobacteria and denitrobacteria, realizing the efficient removal of NH4+-N and TN that occurred in the final PN process with self-cultivated sludge. This work can provide an interesting strategy by rationally combining biological-physicochemical processes for nitrogen removal in toxic industrial wastewaters.