A simple and efficient alternative treatment for different drinking water. Issue 11 (5th November 2022)

• Record Type: Journal Article
• Authors: Zhang, Huiqin; Li, Renwei; Wang, Shulian; Pi, Kewu; Shi, Yafei; Gerson, Andrea R.; Hei, Shengqiang
• Is Part Of: Water Supply. Volume 22:Issue 11(2022)
• Page Start: 8014
• Page End: 8022
• Publication Date: 2022-11-05
• Subjects: ferrate(VI) -- ferric(III) -- multiple treatment mechanisms -- surface water
• DOI: 10.2166/ws.2022.380
• Languages: English
• ISSNs: 1606-9749

Abstract

Abstract: A bench–scale experiment was performed to assess whether union use of ferrate (Fe(VI)) and ferric (Fe(III)) addition in real surface water (reservoir and river water) resulted in better water remediation. The results indicated that increased Fe dosage improved the treatment performance, the removals of total coliform, turbidity and DOC were better when the mass ratio of Fe(VI): Fe(III) was 1:2 and pH was 8, regardless of the water source. Alkalescency condition benefits Fe(III) coagulation and Fe(VI) disinfection efficiency due to the better stability and greater exposure to Fe(VI). Union use of Fe(VI) and Fe(III), as a coagulant and oxidant to enhance flocculation precipitation, can simultaneously remove turbidity, degraded natural organic matter (NOM) degradation, and destroy bacterial activity. At optimized dosage and pH, chemical oxidation plays the dominant role in the disinfection performance and secondary removal of DOC for Fe(VI) treatment, while for the mechanisms of Fe(III), coagulation and adsorption make the dominant contribution to the removal of turbidity and DOC. The application of the optimal ratio can maximize the advantages of both Fe(VI) and Fe(III), and enables the maximum purification effectiveness at minimum dosage and cost, so it will be a simple and efficient treatment for different drinking water. HIGHLIGHTS: Alkalescency condition benefits Fe(III) coagulation and Fe(VI) disinfection efficiency due to the better stability and greater exposure to Fe(VI). The application of the optimal ratio can maximize the advantages of both Fe(VI) and Fe(III), and enables the maximum purification effectiveness at minimum dosage and cost. Graphical Abstract