N. Meftah, Abdessalem Ezzeddine, A. Bédoui, A. Hannachi
{"title":"Hybrid neutralization and membrane process for fluoride removalfrom an industrial effluent","authors":"N. Meftah, Abdessalem Ezzeddine, A. Bédoui, A. Hannachi","doi":"10.12989/MWT.2020.11.4.303","DOIUrl":null,"url":null,"abstract":"This study aims to investigate at a laboratory scale fluorides removal from an industrial wastewater having excessive F- concentration through a hybrid process combining neutralization and membrane separation. For the membrane separation operation, both Reverse Osmosis (RO) and Nanofiltration (NF) were investigated and confronted. The optimized neutralization step with hydrated lime allowed reaching fluoride removal rates of 99.1 ± 0.4 %. To simulate continuous process, consecutive batch treatments with full recirculation of membrane process brines were conducted. Despite the relatively high super saturations with respect to CaF2, no membrane cloaking was observed. The RO polishing treatment allowed decreasing the permeate fluoride concentration to 0.9 ± 0.3 mg/L with a fluoride rejection rate of 93± 2% at the optimal transmembrane pressure of around 100 psi. When NF membrane was used to treat neutralization filtrate, the permeate fluoride concentration dropped to 1.1± 0.4 mg/L with a fluoride rejection rate of 88± 5% at the optimal pressure of around 80 psi. Thus, with respect to RO, NF allowed roughly 20% decrease of the driving pressure at the expense of only 5% drop of rejection rate. Both NF and RO permeates at optimal operating transmembrane pressures respect environmental regulations for reject streams discharge into the environment.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":null,"pages":null},"PeriodicalIF":0.8000,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Membrane Water Treatment","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.12989/MWT.2020.11.4.303","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
引用次数: 1
Abstract
This study aims to investigate at a laboratory scale fluorides removal from an industrial wastewater having excessive F- concentration through a hybrid process combining neutralization and membrane separation. For the membrane separation operation, both Reverse Osmosis (RO) and Nanofiltration (NF) were investigated and confronted. The optimized neutralization step with hydrated lime allowed reaching fluoride removal rates of 99.1 ± 0.4 %. To simulate continuous process, consecutive batch treatments with full recirculation of membrane process brines were conducted. Despite the relatively high super saturations with respect to CaF2, no membrane cloaking was observed. The RO polishing treatment allowed decreasing the permeate fluoride concentration to 0.9 ± 0.3 mg/L with a fluoride rejection rate of 93± 2% at the optimal transmembrane pressure of around 100 psi. When NF membrane was used to treat neutralization filtrate, the permeate fluoride concentration dropped to 1.1± 0.4 mg/L with a fluoride rejection rate of 88± 5% at the optimal pressure of around 80 psi. Thus, with respect to RO, NF allowed roughly 20% decrease of the driving pressure at the expense of only 5% drop of rejection rate. Both NF and RO permeates at optimal operating transmembrane pressures respect environmental regulations for reject streams discharge into the environment.
期刊介绍:
The Membrane and Water Treatment(MWT), An International Journal, aims at opening an access to the valuable source of technical information and providing an excellent publication channel for the global community of researchers in Membrane and Water Treatment related area. Specific emphasis of the journal may include but not limited to; the engineering and scientific aspects of understanding the basic mechanisms and applying membranes for water and waste water treatment, such as transport phenomena, surface characteristics, fouling, scaling, desalination, membrane bioreactors, water reuse, and system optimization.