Antifouling membranes for oily wastewater treatment: Interplay between wetting and membrane fouling

Abstract

Oily wastewater is an extensive source of pollution to soil and water, and its harmless treatment is of great importance for the protection of our aquatic ecosystems. Membrane filtration is highly desirable for removing oil from oily water because it has the advantages of energy efficiency, easy processing and low maintenance cost. However, membrane fouling during filtration leads to severe flux decline and impedes long-term operation of membranes in practical wastewater treatment. Membrane fouling includes reversible fouling and irreversible fouling. The fouling mechanisms have been explored based on classical fouling models, and on oil droplet behaviors (such as droplet deposition, accumulation, coalescence and wetting) on the membranes. Membrane fouling is dominated by droplet-membrane interaction, which is influenced by the properties of the membrane (e.g., surface chemistry, structure and charge) and the wastewater (e.g., compositions and concentrations) as well as the operation conditions. Typical membrane antifouling strategies, such as surface hydrophilization, zwitterionic polymer coating, photocatalytic decomposition and electrically enhanced antifouling are reviewed, and their cons and pros for practical applications are discussed.

Oil fouling in double‐pipe heat exchanger under liquid‐liquid dispersion and the influence of copper oxide nanofluid

“…Heat transfer under liquid‐liquid dispersion conditions is encountered in various industrial applications such as refining of crude oil, processing of oily water, oil‐water separation in wastewater treatment, food and metal processes, and utilization of oilfield geothermal water in which slight oils exist . Oily water contains a wide range of oil concentrations that depend on the industrial processes from which the oily water is produced.…”

Antifouling Property of Oppositely Charged Titania Nanosheet Assembled on Thin Film Composite Reverse Osmosis Membrane for Highly Concentrated Oily Saline Water Treatment

“…The introduction of surface modifiers, such as hydrophilic nanomaterials and antimicrobial polymers, renders excellent fouling resistance and enhanced membrane longevity and performance [ 18 , 19 , 20 , 21 , 22 ]. When dealing with hydrophobic foulant, such as emulsified oil, it is generally agreed that smooth and hydrophilic membrane surfaces can limit the surface–foulant hydrophobic interaction, hence suppressing membrane fouling [ 23 ].…”

Detergent and Water Recovery from Laundry Wastewater Using Tilted Panel Membrane Filtration System

“…Membrane technology has been adopted for water and wastewater treatment due its high separation efficiency as well as its economic and environmental advantages [ 9 ]. However, one of its downsides is membrane fouling, which disallows maintaining high permeate flux over a prolonged operation [ 10 ]. Thereby, membrane fouling complicates the system by increasing both capital and operational expenditure as well as shortening the membrane life-span [ 11 , 12 ].…”