Fouling membrane engineering

These are examples of the construction of a total membrane engineered for fouling resistance. 

Figure 14.1 Causes of membrane fouling and scaling for 150 autopsied membranes. Courtesy ofM. Fnzel and The Engineering Society of Western Pennsylvania.

Microfiltration. Microfiltration, the use of tangential flow anisotropic membranes to permeate the product of choice while retaining solids, can be an attractive cell separation technique because it does not require the use of flocculants or filter aids. It is, in principle, a more technically sophisticated version of classic dead-end filtration processes. Microfiltration yields can be low due to progressive fouling of membranes. Advanced engineering has overcome many of the early... 

DiGiano F.A., Braghetta A., Nilson J., Utne B. (1994), Fouling of nanofiltration membranes by natural organic matter. National Conference on Environmental Engineering, American Society of Civil Engineers, 320-328. 

Mackey E.D. (1999), Fouling of ultrafiltration and nanofilttation membranes by dissolved organic matter. Dissertation, Rice University, Environmental Sdence and Engineering, Houston. 

Zhu, X. (1996), Colloidal fouling of thin film composite and cellulose acetate reverse osmosis membranes, Dissertation, University of California, Civil Engineering, Los Angeles. 

Pagliero, C., Mattea, M., Ochoa, N. A., and Marchese, J. (2007) Fouling of polymeric membranes during degum-ming of crude sunflower and soybean oil. Journal of Food Engineering 78, 194-197. 

S. Rajesh, A. Jayalakshmi, S. Senthilkumar, H.S.H. Sankar, D.R. Mohan, Performance evaluation of poly(amide-imide) incorporated cellulose acetate ultrafiltration membranes in the separation of proteins and its fouling propensity by ARM imaging, Industrial and Engineering Chemistry Research 50 (24) (2011) 14016-14029. 

Zhang, W Park, B. C., Chang, Y. K., Chang, H. N., Yu, X. J., Yuan, Q. (1998). Factors affecting membrane fouling in filtration of Saccharomyces cerevisiae in an internal ceramic filter bioreactor. Bioprocess Engineering, 18, 317—322. 

Long D. Nghiem (removal of trace contaminants by NF/RO membranes membrane fouling and autopsy studies non-potable and indirect potable water reuse membrane bioreactors membrane extraction membrane electrolysis). School of Civil Mining and Environmental Engineering, University of Wollongong (UOW), NSW... 

Victor Starov (influence of surface forces on membrane separation nano-filtration, ultra- and microfiltration (fouling and/or gel layers formation)). Department of Chemical Engineering, Loughborough University, Loughborough... 

The hemocompatibility of hydrophilic materials is relevant for standard blood-contacting medical devices, but there are additional applications for which the protein-resistant properties are useful. Hydrophilic materials play a large role in the membrane industry, where improved wet-out improves solution flow through the membrane additionally, hydrophilic membranes show less protein fouling (55). In the realm of engineering thermoplastics, low protein binding materials are useful in lab equipment and in biopharmaceutical applications... 

Three key elements determine the potential and applications of a hollow-fiber membrane (1) pore size and pore size distribution, (2) selective layer thickness, and (3) inherent properties (chemistry and physics) of the membrane material. Pore size and its distribution usually determine membrane applications, separation factor, or selectivity. The selective layer thickness determines the membrane flux or productivity. Material chemistry and physics govern the intrinsic permselectivity for gas separation and pervaporation, fouling characteristics for RO (reverse osmosis), UF (ultrafiltration), and MF (microfiltration) membranes, chemical resistance for membranes used in harsh environments, protein and drug separation, as well as biocompatibUity for biomedical membranes used in dialysis and biomedical and tissue engineering. 

Chai, G.-Y., Krantz, W. B., and Greenberg, A. R. (2001). Measurement of membrane fouling in spiral-wound modules. Paper presented at the 6th World Congress of Chemical Engineering, Melbourne, Australia, Sept. 23-27, 2001. 

Operation of the virgin and modified AI2O3 manbrane was compared by the separation of an oil-water emulsion, which consisted of 20 engine oil (1 g/L), Tween 80 (0.5 g/L), Span 80 (0.5 g/L), and distilled water. Stable oil-water emulsion had an average droplet size of 1.79 pm, and 90% of the oil droplets were between 0.67 and 7.4 pm. Filtration tests were conducted at the transmanbrane pressure of 0.16 MPa, feed flow rate of 5 m/s, and at an operating temperature of SO C. The membrane was back-flashed at the interval of 10 min. For the virgin AljOj manbrane, the flux declined sharply in the first 60 min, from 446 to 159 L/m h. The steady flux was only about 30% of the initial flux, implying that the AljOj membrane was seriously fouled. However, the flux of the modified membrane quickly reached a constant in 10 min. The flux declined from 506 to 441 L/m h, which is 88% of the initial flux. 

Singh, S., The Mechanism of Fouling and Synthetic Membrane Development for Treating Coating Plant Effluent from a Pulp and Paper Mill , Ph.D. Thesis, Department of Chemical Engineering, University of Ottawa, (1999). 

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