Nanofiltration (loose reverse osmosis, low-pressure reverse osmosis)
- How does it work?
- What can it be used for?
- What can it not be used for?
- Related Facilities
- Further Information
|Key words||liquid-liquid separation, desalination, waste water treatment, drinking water, process water production, monovalent ion, multivalent ion, organic solute, sugar industry, dairy industry, juice, beer, wine, starch, demineralization, whey, protein recovery, peptide recovery, amino acid recovery, pesticides removal, partial desalination, arsenic removal, partial chemical removal, solid-liquid separation, membrane|
|Completed by||Wageningen UR - FBR|
How does it work?
|Primary objective||separation of liquids from liquids (liquid-liquid separation)|
|Working principle|| Nanofiltration designates a membrane separation process, driven by a pressure gradient, in which the membrane separates the solvent (e.g. water, alcohol) from other components (e.g. aromas, metal ions, colours) of a solution. The selectivity of the membrane defines the separation process and depends mostly on membrane material and characteristics of the membrane. Commonly pore sizes are 10-8-10-10m; more commonly the rejection of sodium chloride is given as 20-80 %, molecular cut-off: 200 – 1000 Da. Pressures needed are 350 – 3000 kPa (50 – 450 psig, 3.5 – 30 bar).|
|Additional effects|| Retention of microorganisms in retentate
microbiological decontamination of the permeate
|Important process parameters||pressure (3.5-30 bar), membrane type and material, surface properties of the membrane, surface area of the membrane, temperature, cross flow velocity, solvent resistance of the membrane|
|Important product parameters||viscosity, particle concentration, diffusivity and density, molecular mass higher than 200-1000 Da, particle size in the order of one nanometer|
What can it be used for?
|Operations|| Liquid-liquid separation
(Ion-)Fractionation Purification Partial desalination
|Solutions for short comings||Low energy consumption for some applications.|
What can it NOT be used for?
|Products||Solids, gas, high viscous liquids, aggressive materials (risk of damage of the membrane)|
|Operations|| Solid-liquid separation
|Other limitations|| Membrane fouling
Chemical resistance of the membranes Limitation of concentration Separation between solutes
|Risks or hazards||None|
|Maturity||Lab-scale, pilot-scale and industrial scale possible|
|Modularity /Implementation||Membrane system design offers simple modular expansion and can be inserted in existing production line|
|Consumer aspects||Not available yet|
|Legal aspects||Commonly accepted technology in food processing. No special legislation requirements.|
|Environmental aspects|| NF energy consumption is low when compared with conventional separation techniques
Water consumption is relatively high with respect to the cleaning procedure
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|Institutes||Twente University - Membrane Technology Group, European Membrane Institute Twente, Johannes Keppler Universität Linz - Institut für Verfahrenstechnik, Wageningen UR - FBR|
|Companies||Applied Membranes INC., MMS membrane Systems, Lenntech|
|References|| 1. Van der Bruggen, B., M. Manttari, et al. (2008). Drawbacks of applying nanofiltration and how to avoid them: A review. Separation and Purification Technology 63(2): 251-263.
2. Popov, K. I., A. N. Filippov, et al. (2010). Food nanotechnologies. Russian Journal of General Chemistry 80(3): 630-642.
3. Samhaber, W. M. (2005). Uses and problems of nanofiltration in the food industry. Chemie Ingenieur Technik 77(5): 583-588.
pressure (3.5-30 bar), membrane type and material, surface properties of the membrane, surface area of the membrane, temperature, cross flow velocity, solvent resistance of the membrane viscosity, particle concentration, diffusivity and density, molecular mass higher than 200-1000 Da, particle size in the order of one nanometer Membrane equipment 2.2.1 physical separation nanotechnology Web of knowledge (Searchterms: Nanofiltration AND Food) WikiSysop :Template:Review document :Template:Review status