title: Alkali-solubilized organic matter from sludge and its degradability in the anaerobic process.
abstract: This study investigates alkali-solubilized dissolved organic matter (DOM) and its fate in the anaerobic treatment process. DOM was fractionated into high molecular weight (HMW) protein-like substances (PL), HMW saccharide-like substances (SL), low molecular weight (LMW) PL, LMW SL, and humic acid-like substances (HAL). The results indicate alkali-solubilized DOM is primarily composed of LMW PL, HMW SL, and HAL. Alkaline pretreatment improved the overall anaerobic degradability of DOM in sludge (removal efficiency of total DOM increased by 28.4%). However, certain DOM fractions (mainly HMW PL and HAL) exhibited low degradability during anaerobic treatment, primarily caused by the low degradability of aromatic groups (such as aromatic amine groups from tryptophan-like PL). Alkaline pretreatment also resulted in an increase of residual DOM, which is mainly composed of HAL (52.9%) and HMW SL (49.9%).
authors.affiliation: School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore, Singapore; Advanced Environmental Biotechnology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, CleanTech 1, 637141 Singapore, Singapore.
authors.forename: Dongzhe
authors.initials: D
authors.lastname: Li
authors.affiliation: School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore, Singapore; Advanced Environmental Biotechnology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, CleanTech 1, 637141 Singapore, Singapore.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Advanced Environmental Biotechnology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, CleanTech 1, 637141 Singapore, Singapore.
authors.forename: Youming
authors.initials: Y
authors.lastname: Tan
authors.affiliation: Advanced Environmental Biotechnology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, CleanTech 1, 637141 Singapore, Singapore.
authors.forename: Santosh
authors.initials: S
authors.lastname: Pathak
authors.affiliation: Nanyang Environment and Water Research Institute, Nanyang Technological University, CleanTech 1, 637141 Singapore, Singapore.
authors.forename: Maszenan Bin Abdul
authors.initials: MB
authors.lastname: Majid
authors.affiliation: School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore, Singapore; Nanyang Environment and Water Research Institute, Nanyang Technological University, CleanTech 1, 637141 Singapore, Singapore. Electronic address: wjng@ntu.edu.sg.
authors.forename: Wun Jern
authors.initials: WJ
authors.lastname: Ng
mesh_terms: D000468:Alkalies / Q000737:chemistry*; D000693:Anaerobiosis; D002244:Carbon / Q000737:chemistry; D002845:Chromatography; D006812:Humic Substances / Q000032:analysis*; D008970:Molecular Weight; D009584:Nitrogen / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry*; D012037:Refuse Disposal / Q000379:methods*; D012722:Sewage; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013053:Spectrophotometry; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000468:Alkalies; D006812:Humic Substances; D009930:Organic Chemicals; D012722:Sewage; D002244:Carbon; D009584:Nitrogen
keywords: Anaerobic degradability; Dissolved organic matter; EEM–FRI; FT-IR; LC-OCD-OND