title: Effect of the dosage ratio and the viscosity of PAC/PDMDAAC on coagulation performance and membrane fouling in a hybrid coagulation-ultrafiltration process.
abstract: This study systematically determined the optimal dosage ratio and the viscosity (η) of co-coagulants, polyaluminum chloride (PAC) and poly dimethyldiallylammonium chloride (PDMDAAC), on coagulation performance and membrane fouling in a hybrid coagulation-ultrafiltration (C-UF) process for natural organic matter (NOM) removal. Floc characteristics-including floc size, fractal dimension, strength and re-growth ability-were studied with respect to coagulant-dosing operations. Membrane fouling was evaluated in association with assessment of NOM removal performance by the hybrid process. The best coagulation performance was achieved when PAC and PDMDAAC were dosed with 1.0 mg/L and 0.1 mg/L, respectively. The addition of PDMDAAC could enhance the NOM removal efficiency, especially at low PAC dosages. Co-coagulants PAC/PDMDAAC (ηPDMDAAC= 2.18 dL/g) resulted in formation of the largest flocs with the smallest Dfunder all shear conditions, while the flocs formed by PAC/PDMDAAC (ηPDMDAAC= 1.86 dL/g) had higher recovery abilities. The results from ultrafiltration experiments indicated that coagulation using PAC/PDMDAAC with a viscosity range from 0.99 dL/g to 1.86 dL/g can significantly reduce membrane fouling, leading to increasing water fluxes from 0.1170 to 0.4906 in the ultrafiltration process.
authors.affiliation: Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, Shandong, PR China.
authors.forename: Xue
authors.initials: X
authors.lastname: Shen
authors.affiliation: Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, Shandong, PR China. Electronic address: baoyugao_sdu@aliyun.com.
authors.forename: Baoyu
authors.initials: B
authors.lastname: Gao
authors.affiliation: Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, Shandong, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Huang
authors.affiliation: Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, Shandong, PR China.
authors.forename: Fan
authors.initials: F
authors.lastname: Bu
authors.affiliation: Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, Shandong, PR China.
authors.forename: Qinyan
authors.initials: Q
authors.lastname: Yue
authors.affiliation: Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, Shandong, PR China.
authors.forename: Ruihua
authors.initials: R
authors.lastname: Li
authors.affiliation: School of Chemical Engineering, The University of Adelaide, Adelaide 5005, SA, Australia.
authors.forename: Bo
authors.initials: B
authors.lastname: Jin
mesh_terms: D000536:Aluminum Hydroxide / Q000008:administration & dosage / Q000737:chemistry*; D004866:Equipment Contamination / Q000517:prevention & control*; D005427:Flocculation; D006812:Humic Substances / Q000032:analysis; D008567:Membranes, Artificial; D011095:Polyethylenes / Q000008:administration & dosage / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000008:administration & dosage / Q000737:chemistry*; D014462:Ultrafiltration / Q000295:instrumentation*; D014783:Viscosity; D018508:Water Purification / Q000295:instrumentation* / Q000379:methods
chemical_list: D006812:Humic Substances; D008567:Membranes, Artificial; D011095:Polyethylenes; D000644:Quaternary Ammonium Compounds; C016213:aluminum oxychloride; C041004:poly-N,N-dimethyl-N,N-diallylammonium chloride; D000536:Aluminum Hydroxide
keywords: Coagulation; Floc characteristics; Humic acid; Ultrafiltration; Viscosity