Fouling behavior and performance of microfiltration membranes for whey treatment in steady and unsteady-state conditions

Abstract

Whey pretreatment for protein purification is one of the main applications of cross-flow microfiltration before an ultrafiltration process. In this paper, the effects of the operating pressure and crossflow velocity on the membrane performance and the individual resistances in microfiltration of whey for both unsteady and steady-state conditions were investigated for two 0.45 µm mean pore size polymeric membranes, Polyethersulfone (PES) and Polyvinylidene fluoride (PVDF). A laboratory-scale microfiltration setup with a flat rectangular module was used. The Reynolds number and operating pressure showed positive and negative effects on the amount of all resistances, respectively. The dominant effect of the concentration polarization and cake resistances was demonstrated by using a "Resistance-in-Series" model for unsteadystate investigations, which could vary during the filtration time. An empirical model revealed a linear relationship between the Reynolds number and permeate flux and a second-order polynomial relationship between the transmembrane pressure and the permeate flux. This empirical correlation, implemented for the limited range of MF operating parameters tested in this article for whey protein, was validated with experimental data and showed good agreement between calculated and experimental data.

Electrospun Polyacrylonitrile Nanofibrous Membranes for Point‐of‐Use Water and Air Cleaning

“…The results indicated that the permeability of the membranes was over than 4000 L/(m 2 h bar). However, the permeability reduced gradually through the membrane in time due to several possible reasons such as concentration polarization and membrane fouling ,,. After 3 h of operation, the membrane permeability reached to steady‐state.…”

“…However, the permeability reduced gradually through the membrane in time due to several possible reasons such as concentration polarization and membrane fouling. [26,50,51] After 3 h of operation, the membrane permeability reached to steady-state. Among the all membranes, PAN_110_50_3, PAN_ 110_50_5 and PAN_120_100_3 showed the highest permeability (> 1200 L/(m 2 h bar)) after 6 h of operation.…”

Transport properties and fouling issues of membranes utilized for the concentration of dairy products by air-gap membrane distillation and microfiltration

“…Fouling can impact membrane performance at different ways, e.g., by flux reduction during the process related to the increase of temperature polarization, and thermal resistance, decrease of active membrane area as well as increased tortuosity for mass transfer. This fact is associated with the specific interactions between various solutes present in feed solution and membrane material as well as with the interactions among other solutes in the solution including absorbed solutes (Hausmann et al 2013b;James et al 2003;Rezaei et al 2014). Due to the high complexity of feed stream in the case of dairy product separation, it should be remembred that each component of feed stream will interact in a different way with the material of the membrane (Hausmann et al 2011, b).…”

“…In the following work (Barukčić et al 2015), MF process was used as a pre-treatment step having an important impact on the UF process by enhancing transport properties and reducing fouling, despite the fact that microbial reduction was practically equal to pasteurization. The zeta potential and protein conformation will impact the aforementioned interactions between membrane and feed (Hausmann et al 2013b;Rezaei et al 2014). It is also estimated that the chemistry of the feed components will influence the fouling mechanism during the separation process of dairy products.…”

OBTAINING FRUCTOOLIGOSACCHARIDES FROM YACON (Smallanthus sonchifolius) BY AN ULTRAFILTRATION PROCESS

“…These resistances include membrane resistance, an external or reversible fouling, which consists of cake layer deposition and concentration polarization, and irreversible resistance (Bagci, 2014;Rezaei et al, 2014). The latter is due to particle and macromolecule deposition and adsorption of smaller-sized solutes onto the membrane pore walls (Ng et al, 2014;Rezaei et al, 2014).…”