title: The important implications of particulate substrate in determining the physicochemical characteristics of extracellular polymeric substances (EPS) in activated sludge.
abstract: Since the notable amount of particulate substrate in wastewater, the implications of particulate substrate on treatment efficiency have been a topic of major interest in the field of biological wastewater treatment. The particulate substrate has to be hydrolyzed by the extracellular enzymes, which are mainly embedded in extracellular polymeric substances (EPS) matrix of microbial aggregates, prior to consumption. Therefore, the important relevance between the particulate substrate and the characteristics of EPS can be expected. In this study, two lab-scale sequencing batch reactors were performed in parallel to investigate the effects of particulate and soluble substrate on the physicochemical characteristics of EPS in activated sludge. The results showed that the particulate substrate in the influent could significantly change the properties of activated sludge and the characteristics of EPS. More open and fluffy flocs with poorer settleability and dewaterability were formed with particulate substrate. More protein and humic compounds were introduced into the EPS matrix due to the deep involvement of protein and humic compounds in hydrolysis process of particulate substrate. The increments of protein and humic compounds then caused the slight higher molecular weight, higher hydrophobicity and lower zeta potential of EPS in particulate substrate system. The results in this study permitted for obtaining answers to understand the significant implications of particulate substrate in determining the physicochemical characteristics of EPS in biological wastewater treatment systems.
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an 710055, China. Electronic address: bbwangchn@gmail.com.
authors.forename: Bin-Bin
authors.initials: BB
authors.lastname: Wang
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an 710055, China.
authors.forename: Dang-Cong
authors.initials: DC
authors.lastname: Peng
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an 710055, China.
authors.forename: Yin-Ping
authors.initials: YP
authors.lastname: Hou
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an 710055, China.
authors.forename: Hui-Juan
authors.initials: HJ
authors.lastname: Li
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an 710055, China.
authors.forename: Li-Ying
authors.initials: LY
authors.lastname: Pei
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an 710055, China.
authors.forename: Li-Fang
authors.initials: LF
authors.lastname: Yu
mesh_terms: D005110:Extracellular Space / Q000737:chemistry; D008970:Molecular Weight; D011108:Polymers / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry; D012722:Sewage / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D062065:Wastewater / Q000737:chemistry
chemical_list: D011108:Polymers; D011506:Proteins; D012722:Sewage; D062065:Wastewater
keywords: Activated sludge; Cation exchange resin; Extracellular polymeric substances; Particulate substrate; Physicochemical characteristics