Dynamic Membrane Filtration: Formation, Filtration, Cleaning, and Applications

Abstract

Applications of dynamic membrane (DM) filtration and factors affecting formation, filtration, and cleaning are introduced. DMs have been studied extensively for wastewater treatment in recent years. DM formation methods and mechanisms are explained. Effects of supporting material, deposited material, formation pressure, and pH on the DM formation are discussed in detail. The impacts of operation pressure, aeration intensity, cross-flow velocity, temperature, and other parameters on the DM filtration process are evaluated and different DM cleaning strategies are reviewed. The applications of DMs to treatments of municipal wastewater, surface water, oily water, industrial wastewater, sludge, and microalgae harvesting are discussed. Finally, possible future research directions and some guidelines for DM technology are given.

Effect of pore size of monofilament woven filter cloth as supporting material for dynamic membrane filtration on performance using aerobic membrane bioreactor technology

“…Generally, the large pore filter cloth has a larger active filtration area and less filtration resistance than the small pore filter cloth. So the larger pore filter cloth enables a higher filtration flux under the same operation pressure 18 . The selection of an appropriate pore size of the supporting membrane is a balance between DM formation time, filtration flux, and pollutant removal efficiency.…”

“…Principally, DM consists of two main layers, namely, a supporting layer and a deposited layer 18, 19 . The supporting layer provides support for the deposited layer to be attached, whereby this layer acts as the functional membrane part, which can replace ultrafiltration (UF)/microfiltration (MF) membranes 12 .…”

Pre‐deposited dynamic membrane adsorber formed of microscale conventional iron oxide‐based adsorbents to remove arsenic from water: application study and mathematical modeling

“…This suggests that a DM filter technology predominantly involves two layers, namely the primary membrane as a supporting layer and the deposited cake layer of microparticles as the secondary membrane. The primary membrane offers the foundation to the deposited layer, while the deposited layer, consisting of nano‐ and microparticles, acts as the dominant functional part for decontamination of water 5 . The deposited layer of particles then determines the removal rates and efficiency of the DM filter towards a target trace pollutant, 2,6 when the primary membrane does not have a rejection capacity towards the specific target pollutant 2 .…”

“…The DM filter with diverse separating functions can be developed by opting suitable pre‐depositing materials. The DM filter made on loosened support materials such as MF and mesh has an advantage over traditional membranes of operating under gravity‐driven mode 5 . A driving force by means of a 10 cm water head was sufficient during DM filtration of secondary wastewater effluent to achieve 200 L m −2 h −1 when a nylon mesh with an corresponding aperture of 25 μm was applied as a DM support material 9 .…”

“…DM filters are categorized into two main types: self‐forming DM filters and pre‐deposited DM filters. In the first case, the feed constituents are those which form the DM filter, whereas the pre‐deposited DM filter are developed as a result of deposition of particles other than the feed solution at the top surface of the primary membrane prior to the inflow of the polluted water 2,4,5 . The pre‐deposited DM filter offers the flexibility of selecting appropriate and affordable materials which might be used to develop the membrane filter.…”