Simulation of continuous stirred ultrafiltration process: an approach based on surface renewal theory

Abstract

Ultrafiltration (UF) is an important operation in many processes, including foods and pharmaceuticals, and shear enhanced dead‐end systems are particularly suitable for small‐scale operations. Most industrial applications require a high permeate flux and maximum solute rejection, combined with long membrane life. A rigorous surface renewal model has been developed which describes the mass transfer processes occurring in a single stirred UF cell. The model takes into consideration two distribution functions of random surface elements, one with respect to their point of origin and the other related to the corresponding residence time on the membrane surface. The back transport flux and the permeate flux are evaluated at the membrane surface in order to develop a component balance equation. The component balance equation and a rejection–flux relationship arising from irreversible thermodynamics are solved simultaneously to allow a dynamic simulation. The dynamic simulation enables a more complete understanding of the permeate flux, membrane surface concentration and permeate concentration under various operating conditions. For validation of the proposed model, experiments were conducted on UF of polyethylene glycol 6000 (PEG 6000) solution in a continuous stirred UF cell comprising a cellulose acetate membrane of 5000 Da molecular weight cut‐off. Model predicted values are in excellent agreement with the experimental results. The effects of different stirring mechanisms on mass transfer with flat disk, propeller and turbine impellers were also characterized using the developed model. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.

Generation and Release Mechanism and Abatement Measures for Gas Supersaturation Downstream of Hydropower Dams: A Review

“…Li et al, 2000; W. S. Luo et al, 2003;X. B. Luo et al, 2021;Matheron & Sandall, 1978;Ojo & Ghanbar, 2019;Sarkar et al, 2012;. The theoretical models and calculation formulas of mass transfer coefficient are shown in Table 1.…”

“…Two‐film theory, percolation theory, and surface renewal theory are the three traditional mass transfer theoretical frameworks for resolving the mass transfer coefficient K as shown in Figure 4 (B. Fu et al., 2013; R. Li et al., 2000; W. S. Luo et al., 2003; X. B. Luo et al., 2021; Matheron & Sandall, 1978; Ojo & Ghanbar, 2019; Sarkar et al., 2012; C. Wang et al., 2018). The theoretical models and calculation formulas of mass transfer coefficient are shown in Table 1.…”

Extensive review about industrial and laboratory dynamic filtration modules: Scientific production, configurations and performances

“…Due to the complex composition of industrial wastewater, simple solutions, emulsions and solid-liquid suspensions were preferred as test fluids. Simple solutions were used to mitigate toxic pollutants (halogenated organic compounds [39,40], 2-MIB and geosmin [41], polyvinyl alcohol [42], heavy metal ions [43,44] and sodium dodecylbenzene sulfonate [45,46]), artificial seawater (NaCl, KCl, MgCl2, CaCl2, and MgSO4) [47,48], viscous solutions (polyethylene glycol-6000 [49][50][51], carboxymethyl cellulose [52], ethanol [53]), soluble salts (CaSO4 [54], NaCl [55]), model wastewater in dairy process [56][57][58][59][60][61][62] and space mission [63]. For emulsion, oil/water mixtures with surfactants were considered [64][65][66][67][68][69][70].…”

“…A shear-enhanced system, namely rotating disk-membrane (RD-M) modules, were investigated on microfiltration of black liquor [32,33], Ultrafiltration of PEG 6000 and Bovine serum albumin [49,51,141]. The membrane was placed on disk-shaped porous support with an effective filtration area of 24.6 cm 2 .…”

Effects of concentration dependent local resistances and viscosity on overall permeation characteristics of a hollow‐fiber membrane: A simulation approach

“…Ultrafiltration is one of the most successful pressure driven membrane-based separation process, widely used in bio-processing industries for the purpose of protein separation, and for the purification and concentration of macromolecular solution. 1,2 Ultrafiltration is very similar to conventional filtration method with the exception of separation taking place at the molecular level (having membrane pore size 1-100 nm). A hollow-fiber membrane module is one of the most useful modules in which fine tubular membranes are mounted inside the polymer cylinder to provide large specific area per unit volume.…”