title: Fate of extracellular polymeric substances of anaerobically digested sewage sludge during pre-dewatering conditioning with Acidithiobacillus ferrooxidans culture.
abstract: This study investigated the fate of extracellular polymeric substances (EPS) of anaerobically digested saline sewage sludge during its preconditioning. Sludge was conditioned with Acidithiobacillus ferrooxidans (AF) culture for 24h in the presence and absence of Fe(2+) as an energy substrate. pH decreased from 7.24 to 3.12 during sludge conditioning process. The capillary suction time (CST) of conditioned sludge significantly decreased to <10s, and specific resistance to filtration (SRF) was reduced by >94% as compared with control within 4h of conditioning with or without Fe(2+), indicating a significant (P<0.001) improvement in sludge dewaterability. A noticeable decrease in extractable EPS was observed in conditioned sludge. The EPS contents showed a significant negative correlation with dewaterability of sludge (P<0.05). The results suggest that bioacidification treatment using A. ferrooxidans effectively improved sludge dewaterability through modification of sludge EPS.
authors.affiliation: Sino-Forest Applied Research Centre for Pearl River Delta Environment, Hong Kong Baptist University, Hong Kong Special Administrative Region; Department of Environmental Science, Periyar University, Salem, India.
authors.forename: Kumarasamy
authors.initials: K
authors.lastname: Murugesan
authors.affiliation: Sino-Forest Applied Research Centre for Pearl River Delta Environment, Hong Kong Baptist University, Hong Kong Special Administrative Region.
authors.forename: Balasubramani
authors.initials: B
authors.lastname: Ravindran
authors.affiliation: Sino-Forest Applied Research Centre for Pearl River Delta Environment, Hong Kong Baptist University, Hong Kong Special Administrative Region; Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region.
authors.forename: Ammaiyappan
authors.initials: A
authors.lastname: Selvam
authors.affiliation: Sino-Forest Applied Research Centre for Pearl River Delta Environment, Hong Kong Baptist University, Hong Kong Special Administrative Region.
authors.forename: Mayur B
authors.initials: MB
authors.lastname: Kurade
authors.affiliation: Sino-Forest Applied Research Centre for Pearl River Delta Environment, Hong Kong Baptist University, Hong Kong Special Administrative Region; Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region.
authors.forename: Shuk-Man
authors.initials: SM
authors.lastname: Yu
authors.affiliation: Sino-Forest Applied Research Centre for Pearl River Delta Environment, Hong Kong Baptist University, Hong Kong Special Administrative Region; Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region. Electronic address: jwcwong@hkbu.edu.hk.
authors.forename: Jonathan W C
authors.initials: JW
authors.lastname: Wong
mesh_terms: D042763:Acidithiobacillus; D019149:Bioreactors / Q000382:microbiology*; D005374:Filtration; D006863:Hydrogen-Ion Concentration; D011108:Polymers / Q000737:chemistry*; D012722:Sewage / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D011108:Polymers; D012722:Sewage
keywords: Acidithiobacillus ferrooxidans; Anaerobically digested sludge; Bioflocculant; Extracellular polymeric substances; Sludge dewaterability