Performance and autopsy of nanofiltration membranes at an oil-field wastewater desalination plant

Investigation of the applicability of TiO2, BiVO4, and WO3 nanomaterials for advanced photocatalytic membranes used for oil‐in‐water emulsion separation

“…Therefore, the development of effective treatment methods of oily wastewaters is of great interest 15,16 . To comply with the stringent emission limits, conventional techniques—such as skimming, 17 sand filtration, 18 centrifugation, 19 flotation, 20 adsorption, 5 or chemical destabilization 21,22 —must be augmented with advanced method(s) such as membrane filtration, which can eliminate the usually remaining microsized and nanosized oil droplets 23–26 …”

“…Membrane filtration has numerous advantages, like high purification efficiency, facile operation, easy integration, and the absence of chemical additives 26,27 . However, for its economic utilization, the mitigation of membrane fouling needs to be solved, especially in the case of oily wastewaters, because the formation of hydrophobic layer results in significant flux reduction, which reduces the productivity and life span of the membrane and increases the energy consumption and the cost of the treatment 25 . A promising way to solve the flux reduction is to minimize the interaction between the oily foulants and membrane surface by improving the membrane's hydrophilicity 28,29 .…”

Intensification of the ultrafiltration of real oil-contaminated (produced) water with pre-ozonation and/or with TiO2, TiO2/CNT nanomaterial-coated membrane surfaces

“…This enables the effective elimination of not just the floating and dispersed oil but the emulsified micro-and nano-sized oil droplets as well. As membrane filtration, microfiltration (Abadi et al 2011;Hu et al 2015;Masoudnia et al 2014;Salahi et al 2010;Shokrkar et al 2012;Zhang et al 2018), ultrafiltration (Masoudnia et al 2014;Saki and Uzal 2018;Salahi et al 2010;Yi et al 2011), nanofiltration (Golpour and Pakizeh 2017;Zhao et al 2019), or even reverse osmosis (Kasemset et al 2013) can be used, resulting in increasing purification efficiency in this order.…”

“…However, fouling has been a crucial challenge of membrane filtration processes since the birth of this technology, especially in the case of oil-in-water emulsions. Oily contaminants quickly form a hydrophobic layer acting as a significant water barrier on the membrane surface, which reduces water flux, decreases membrane lifespan, and increases energy consumption (Liu et al 2018;Matos et al 2016;Padaki et al 2015;Yin and Zhou 2015;Zhao et al 2019).…”

Analytical solutions of polymer transport in porous media under magnetic effect

“…On the other hand, the magnetic field can be used with polymers in some applications such as the magnetic nanoparticles implementation to eliminate pollutants from the produced water without chemicals [7][8][9][10]. Another example is the usage of magnetic resonance imaging and measurements to monitor oil displacement by water-flooding and polymer flooding [11].…”