title: A novel conditioning process for enhancing dewaterability of waste activated sludge by combination of zero-valent iron and persulfate.
abstract: Improvement of sludge dewaterability is crucial for reducing the costs of sludge disposal in wastewater treatment plants. This study presents a novel conditioning method for improving waste activated sludge dewaterability by combination of persulfate and zero-valent iron. The combination of zero-valent iron (0-30g/L) and persulfate (0-6g/L) under neutral pH substantially enhanced the sludge dewaterability due to the advanced oxidization reactions. The highest enhancement of sludge dewaterability was achieved at 4g persulfate/L and 15g zero-valent iron/L, with which the capillary suction time was reduced by over 50%. The release of soluble chemical oxygen demand during the conditioning process implied the decomposition of sludge structure and microorganisms, which facilitated the improvement of dewaterability due to the release of bound water that was included in sludge structure and microorganism. Economic analysis showed that the proposed conditioning process with persulfate and ZVI is more economically favorable for improving WAS dewaterability than classical Fenton reagent.
authors: Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors: Xu
authors: X
authors: Zhou
authors: Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors: Qilin
authors: Q
authors: Wang
authors: Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors: Guangming
authors: G
authors: Jiang
authors: Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland 4072, Australia.
authors: Peng
authors: P
authors: Liu
authors: Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland 4072, Australia. Electronic address: zhiguo@awmc.uq.edu.au.
authors: Zhiguo
authors: Z
authors: Yuan
mesh_terms: D057919:Biological Oxygen Demand Analysis; D001709:Biotechnology / Q000379:methods*; D002623:Chemistry Techniques, Analytical; D006861:Hydrogen Peroxide; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D012722:Sewage / Q000737:chemistry; D013440:Sulfides / Q000737:chemistry*; D062065:Wastewater; D014867:Water / Q000737:chemistry; D018508:Water Purification / Q000379:methods
chemical_list: D006861:Hydrogen Peroxide; D007501:Iron; D010100:Oxygen; D012722:Sewage; D013440:Sulfides; D062065:Wastewater; D014867:Water; C045076:Fenton's reagent; C051552:persulfides
keywords: Advanced oxidization processes; Dewaterability; Persulfate; Waste activated sludge; Zero-valent iron