title: Bacterial polymer production using pre-treated sludge as raw material and its flocculation and dewatering potential.
abstract: Sterilization, alkaline-thermal and acid-thermal treatments were applied to different sludge solids concentrations (17.0; 22.4; 29.8; 37.3; 44.8 g/L, respectively) and the pre-treated sludge was used as raw material for Serratia sp.1 to produce extracellular polymeric substances (EPS). After 72 h of fermentation, total EPS of 2.3 and 3.4 g/L were produced in sterilized and alkaline-thermal treated sludge as compared to that of 1.5 g/L in acid-thermal treated sludge. Lower EPS were produced at relatively higher solids concentrations (37.3; 44.8 g/L). Broth, crude forms of capsular and slime EPS were extracted from fermented broths and used as conditioning agents by combining with 150 mg of Ca(2+)/L of kaolin suspensions. Maximum flocculation activity of 79.1% and increased dewatering by 52.2% was achieved using broth and crude capsular EPS, respectively. The results demonstrated that EPS having high flocculating capability could be produced using wastewater sludge as sole raw material.
authors.affiliation: Institut national de la recherche scientifique, Centre Eau, Terre et, Environnement, Université du Québec, 490 de la Couronne, Québec (QC), G1K 9A9, Canada. more.tanaji@gmail.com
authors.forename: T T
authors.initials: TT
authors.lastname: More
authors.forename: S
authors.initials: S
authors.lastname: Yan
authors.forename: N V
authors.initials: NV
authors.lastname: Hoang
authors.forename: R D
authors.initials: RD
authors.lastname: Tyagi
authors.forename: R Y
authors.initials: RY
authors.lastname: Surampalli
mesh_terms: D057919:Biological Oxygen Demand Analysis; D001704:Biopolymers / Q000096:biosynthesis*; D019149:Bioreactors; D005427:Flocculation; D006358:Hot Temperature; D007616:Kaolin; D012705:Serratia / Q000378:metabolism*; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology; D062065:Wastewater / Q000737:chemistry*; D014867:Water / Q000378:metabolism
chemical_list: D001704:Biopolymers; D007616:Kaolin; D012722:Sewage; D062065:Wastewater; D014867:Water