Removal of Emerging Contaminants from Wastewater Streams Using Membrane Bioreactors: A Review

Abstract

Water is a very valuable natural resource. As the demand for water increases the presence of emerging contaminants in wastewater has become a growing concern. This is particularly true when one considers direct reuse of wastewater. Obtaining sufficient removal of emerging contaminants will require determining the level of removal for the various unit operations in the wastewater treatment process. Membrane bioreactors are attractive as they combine an activated sludge process with a membrane separation step. They are frequently used in a wastewater treatment process and can operate at higher solid loadings than conventional activated sludge processes. Determining the level of removal of emerging contaminants in the membrane bioreactor step is, therefore, of great interest. Removal of emerging contaminants could be by adsorption onto the biomass or membrane surface, biotransformation, size exclusion by the membrane, or volatilization. Given the fact that most emerging contaminants are low molecule weight non-volatile compounds, the latter two methods of removal are usually unimportant. However, biotransformation and adsorption onto the biomass are important mechanisms of removal. It will be important to determine if the microorganisms present at given treatment facility are able to remove ECs present in the wastewater.

A critical review on diverse technologies for advanced wastewater treatment during SARS-CoV-2 pandemic: What do we know?

“…In addition, membrane bioreactors (MBRs) are considered an advanced technology for the treatment of wastewater, mainly to produce high-quality effluent suitable for reuse ( Sengupta et al 2021 ), including for the treatment of emerging contaminants ( Nguyen et al 2022 ). The technology has matured and has been widely implemented with a growing market share at about a 15% rate, mainly when aiming for effluent reuse ( Hoinkis et al 2012 ) and sustainability ( Holloway et al 2016 ).…”

Energy-Efficient AnMBRs Technology for Treatment of Wastewaters: A Review

“…It should be kept in mind that, although great progress was made in recent years regarding investigations of the fouling phenomenon, it is still impossible to predict its degree in AnMBRs. This is mainly due to the variation in the wastewater characteristics, including the composition and pH, as well as the nature of the contaminants [135]. Nevertheless, since the costs of AnMBRs are centered on fouling, its mitigation is extensively investigated for commercial applications [39].…”

Enhanced Electro-Fenton Degradation of Ciprofloxacin by Membrane Aeration

“…Membrane aeration technology, using porous membranes that contain a large number of micrometer or nanometer pores as dispersers to introduce gas into liquid phase in the form of microbubbles, has been reported as a promising microdispersion technology for intensifying the mass-transfer performance and facilitating gas dissolution in gas–liquid heterogeneous systems. − Compared with conventional large bubbles, microbubbles have many unique characteristics that enable them to achieve improved gas–liquid mass transfer efficiency and increased dissolved O 2 concentration. , The surface tension of the gas–liquid interface will cause additional pressure inside bubbles according to the Young–Laplace eq (eq )­ where Δ P is the pressure difference between the inside and outside of the bubble, σ the surface tension, r the radius of the bubble. The smaller bubble radius creates higher internal pressure.…”