title: Nanofiltration based water reclamation from tannery effluent following coagulation pretreatment.
abstract: Coagulation-nanofiltration based integrated treatment scheme was employed in the present study to maximize the removal of toxic Cr(VI) species from tannery effluents. The coagulation pretreatment step using aluminium sulphate hexadecahydrate (alum) was optimized by response surface methodology (RSM). A nanofiltration unit was integrated with this coagulation pre-treatment unit and the resulting flux decline and permeate quality were investigated. Herein, the coagulation was conducted under response surface-optimized operating conditions. The hybrid process demonstrated high chromium(VI) removal efficiency over 98%. Besides, fouling of two of the tested nanofiltration membranes (NF1 and NF3) was relatively mitigated after feed pretreatment. Nanofiltration permeation fluxes as high as 80-100L/m(2)h were thereby obtained. The resulting permeate stream quality post nanofiltration (NF3) was found to be suitable for effective reuse in tanneries, keeping the Cr(VI) concentration (0.13mg/L), Biochemical Oxygen Demand (BOD) (65mg/L), Chemical Oxygen Demand (COD) (142mg/L), Total Dissolved Solids (TDS) (108mg/L), Total Solids (TS) (86mg/L) and conductivity levels (14mho/cm) in perspective. The process water reclaiming ability of nanofiltration was thereby substantiated and the effectiveness of the proposed hybrid system was thus affirmed.
authors.affiliation: Department of Chemical Engineering, National Institute of Technology Durgapur, West Bengal 713209, India.
authors.forename: J
authors.initials: J
authors.lastname: Dasgupta
authors.affiliation: Department of Chemical Engineering, National Institute of Technology Durgapur, West Bengal 713209, India.
authors.forename: D
authors.initials: D
authors.lastname: Mondal
authors.affiliation: Department of Informatics, Modeling, Electronics and Systems Engineering, University of Calabria, Via P. Bucci, Cubo-42a, 87036 Rende, CS, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Chakraborty
authors.affiliation: Department of Chemical Engineering, National Institute of Technology Durgapur, West Bengal 713209, India. Electronic address: umuniqueme1@gmail.com.
authors.forename: J
authors.initials: J
authors.lastname: Sikder
authors.affiliation: Department of Informatics, Modeling, Electronics and Systems Engineering, University of Calabria, Via P. Bucci, Cubo-42a, 87036 Rende, CS, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Curcio
authors.affiliation: Institute Center for Water and Environment (iWater), Department of Chemical and Environmental Engineering, Masdar Institute of Science and Technology, PO Box 54224, Abu Dhabi, United Arab Emirates.
authors.forename: H A
authors.initials: HA
authors.lastname: Arafat
mesh_terms: D000534:Alum Compounds / Q000737:chemistry; D057919:Biological Oxygen Demand Analysis; D002857:Chromium / Q000032:analysis; D005374:Filtration; D007220:Industrial Waste; D036103:Nanotechnology / Q000379:methods*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis; D018508:Water Purification / Q000379:methods*
chemical_list: D000534:Alum Compounds; D007220:Industrial Waste; D014874:Water Pollutants, Chemical; D014867:Water; D002857:Chromium; C041524:aluminum sulfate
keywords: Chromium(VI) removal; Nanofiltration; Response surface optimization; Tannery wastewater; Water reclamation