title: Possibility of sludge conditioning and dewatering with rice husk biochar modified by ferric chloride.
abstract: Rice husk biochar modified by FeCl3 (MRB-Fe) was used to enhance sludge dewaterability in this study. MRB-Fe preparation conditions and dosage were optimized. Mechanisms of MRB-Fe improving sludge dewaterability were investigated. The optimal modification conditions were: FeCl3 concentration, 3mol/L; ultrasound time, 1h. The optimal MRB-Fe dosage was 60% DS. Compared with raw sludge, the sludge specific resistance to filtration (SRF) decreased by 97.9%, the moisture content of sludge cake decreased from 96.7% to 77.9% for 6min dewatering through vacuum filtration under 0.03MPa, the SV30% decreased from 96% to 60%, and the net sludge solids yield (YN) increased by 28 times. Positive charge from iron species on MRB-Fe surface counteracted negative charge of sludge flocs to promote sludge settleability and dewaterability. Meanwhile, MRB-Fe kept a certain skeleton structure in sludge cake, making the moisture pass through easily. Using MRB-Fe, therefore, for sludge conditioning and dewatering is promising.
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wu
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China. Electronic address: zhangpanyue@hnu.edu.cn.
authors.forename: Panyue
authors.initials: P
authors.lastname: Zhang
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
authors.forename: Haibo
authors.initials: H
authors.lastname: Zhang
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
authors.forename: Guangming
authors.initials: G
authors.lastname: Zeng
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Liu
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Ye
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Fang
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
authors.forename: Xiying
authors.initials: X
authors.lastname: Gou
mesh_terms: D002606:Charcoal / Q000737:chemistry*; D002712:Chlorides / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D005374:Filtration; D007501:Iron / Q000737:chemistry; D012275:Oryza / Q000737:chemistry; D012722:Sewage / Q000737:chemistry*; D014465:Ultrasonics / Q000379:methods
chemical_list: D002712:Chlorides; D005290:Ferric Compounds; D012722:Sewage; C540010:biochar; D002606:Charcoal; D007501:Iron; C024555:ferric chloride
keywords: Charge neutralization; Incompressibility; Modified rice husk biochar by FeCl(3) (MRB–Fe); Permeability; Sludge dewaterability