title: Effects of magnetic nanoparticles on aerobic granulation process.
abstract: A novel granulation strategy by introducing magnetic nanoparticles (MNPs) into activated sludge system was investigated in this study. The study of the physicochemical characteristics (appearances, sizes, sludge volume index, and chemical oxygen demand) demonstrated that MNPs could decrease the granulation time and improve the retention of biomass, meanwhile enhanced the compact structure of the granules. The secretion and functional groups especially OH and CO of extracellular polymeric substances (EPS) also had significant changes under the long-term influence of MNPs. The contents of proteins (PN) and polysaccharides (PS) in R2 (with MNPs) were 95.7523mg/gVSS and 43.7129mg/gVSS, while in R1 (without MNPs) they were 85.7523mg/gVSS and 32.8632mg/gVSS, respectively. The contact angles of sludge against water dramatically increased with the increase of MNPs concentration, which means that the addition of MNPs could improve the sludge surface hydrophobicity, playing a positive role in the aggregation process.
authors.affiliation: Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, PR China.
authors.forename: Xue-You
authors.initials: XY
authors.lastname: Liang
authors.affiliation: Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, PR China.
authors.forename: Bao-Yu
authors.initials: BY
authors.lastname: Gao
authors.affiliation: Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, PR China. Electronic address: sqni@sdu.edu.cn.
authors.forename: Shou-Qing
authors.initials: SQ
authors.lastname: Ni
mesh_terms: D000332:Aerobiosis; D057919:Biological Oxygen Demand Analysis; D018533:Biomass; D019149:Bioreactors; D058185:Magnetite Nanoparticles; D011108:Polymers / Q000737:chemistry; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D058185:Magnetite Nanoparticles; D011108:Polymers; D012722:Sewage
keywords: Aerobic granulation; Extracellular polymeric substances; FT-IR; Magnetic nanoparticles; XPS