A microgrooved membrane based gas–liquid contactor

Abstract

This research presents an approach for applying microgrooved membranes for improved gas-liquid contacting. The study involves analysis of the performance of the microdevice by quantifying the flux enhancement for different membrane configurations. Two kinds of configurations, continuous and non-continuous grooves, were investigated. The microgrooves provide shear-free gasliquid interfaces, which result in local slip velocity at the gas-liquid interface. Exploiting this physical phenomenon, it is possible to reduce mass transport limitations in gasliquid contacting. An experimental study using grooved membranes suggests enhancement in flux up to 20-30 %. The flux enhancement at higher liquid flow rates is observed due to a partial shear-free gas-liquid interface. The performance of the membrane devices decreased with wetted microgrooves due to the mass transport limitations. The flow visualization experiments reveal wetting of the microgrooves at higher liquid flow rates. According to the numerical and experimental study, we have shown that microgrooved membranes can be employed to improve gas-liquid contacting processes.

Momentum and mass transport over a bubble mattress: the influence of interface geometry

“…4 Various studies have been performed to address the inuence of wall slip on interfacial transport in electro-osmotic ows, [4][5][6][7] in thin lm evaporation in microchannels, 8 and in heat and mass transfer through permeable surfaces. [9][10][11][12][13] It is found that the concentration polarisation at membrane walls decreases with increasing slip, which results in higher interfacial mass transfer rates. 10,[14][15][16] In general, all these studies report a signicant amplication of the transport process under consideration in the presence of a slippery interface.…”

“…However, slippage can be increased signicantly by micro-structuring of the hydrophobic surface with posts, grooves, or cavities that are positioned transversely, longitudinally, or obliquely to the main ow direction. 13,[23][24][25][26][27][28][29][30][31] As gas is entrapped in these micro-structures, the liquid is in contact with a heterogeneous gas-solid interface characterised by partial slip conditions. Measured apparent or effective slip lengths on such superhydrophobic surfaces range from 10 0 to 10 2 mm.…”

Micropatterning of alumina tubular membranes via laser carving for enhanced direct air capture

“…Furthermore, such micropatterns will promote turbulent flow due to increased surface roughness and hence mass transfer coefficient. 14 Micropatterns on ceramic surfaces have been conducted by various techniques such as replication. 15 anodization, 16 hydrothermal methods, 17 soft lithography, 18 laser carving, [19][20][21] chemical etching, 22 or powder blasting with the help of PDMS mask.…”

Facile Preparation of a Superhydrophobic iPP Microporous Membrane with Micron-Submicron Hierarchical Structures for Membrane Distillation

“…Unlike these methods, Wessling et al [32] proposed a unique method called phase separation micro-molding (PSµM). The polymer solution was cast into a microgrooved mold and then immersed in a coagulation bath.…”