title: Immobilized and MgSO4induced cost effective bacterial disintegration of waste activated sludge for effective anaerobic digestion.
abstract: In this study, an attempt was made to disintegrate waste activated sludge (WAS) in a cost-effective way. During the first phase of this study, effective break down of extracellular polymeric substance (EPS) was performed by deflocculating WAS with 0.1 g/g SS of MgSO4. Deflocculation rate was 92% with discharge rate of extractable EPS at 185 mg/L. In the second phase, effective bacterial cell disintegration was obtained at 36 h post treatment. Maximum solubilization of deflocculated sludge was approximately 21%, which was higher than that of flocculated sludge (14.2%) or the control (4.5%). Biodegradability studies were assessed through kinetic analysis by non-linear regression modeling. Results revealed that the deflocculated sludge had higher methane generation (at about 235.8 mL/gVs) compared to flocculated sludge (at 146.1 mL/gVs) or the control (at 34.8 mL/gVs). Cost assessment of the present work revealed that the net yield for each ton of the deflocculated sludge was about 32.99 USD.
authors.affiliation: Department of Civil Engineering, Regional Centre of Anna University, Tirunelveli, India.
authors.forename: U
authors.initials: U
authors.lastname: Ushani
authors.affiliation: Department of Civil Engineering, Regional Centre of Anna University, Tirunelveli, India.
authors.forename: J
authors.initials: J
authors.lastname: Rajesh Banu
authors.affiliation: Department of Civil Engineering, Regional Centre of Anna University, Tirunelveli, India.
authors.forename: S
authors.initials: S
authors.lastname: Kavitha
authors.affiliation: Department of Civil Engineering, Ponjesly College of Engineering, Nagercoil, India.
authors.forename: S
authors.initials: S
authors.lastname: Kaliappan
authors.affiliation: Graduate School of Water Resource, Sungkyunkwan University, Suwon, South Korea.
authors.forename: Ick Tae
authors.initials: IT
authors.lastname: Yeom
mesh_terms: D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D004467:Economics; D005427:Flocculation; D007700:Kinetics; D008278:Magnesium Sulfate / Q000737:chemistry; D008697:Methane / Q000032:analysis; D012722:Sewage / Q000382:microbiology*
chemical_list: D012722:Sewage; D008278:Magnesium Sulfate; D008697:Methane
keywords: Anaerobic biodegradability; Chemical oxygen demand; Degree of deflocculation; Extracellular polymeric substance; Immobilized bacteria; Non-linear regression modeling