understanding the basics of membrane filtration chen 320 – group 7
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Understanding the Basics of Membrane Filtration CHEN 320 – Group 7. Lianne Monterroso Scott Shelton Patricia Stratton Emily Wilborn. Roadmap. Introduction to Membrane Filtration Pressure-Driven Membrane Separation Membrane Materials, Structure, and Morphology - PowerPoint PPT PresentationTRANSCRIPT
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Lianne Monterroso Scott Shelton
Patricia Stratton Emily Wilborn
UNDERSTANDING THE BASICS OF
MEMBRANE FILTRATION
CHEN 320 – GROUP 7
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Introduction to Membrane Filtration
Pressure-Driven Membrane Separation
Membrane Materials, Structure, and Morphology
Membrane Format and Module Design MATLAB Code
Common Membrane Applications
Conclusion
ROADMAP
http://socialmediastrategiessummit.com/blog/a-roadmap-to-ensure-that-strategy-not-tactics-drives-your-social-media/roadmap/
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Accounts for 40% to 70% of capital and operating costs in the chemicals industry
Broad range of applications Process Water Treatment Wastewater treatment
and reuse Metal and catalyst
recovery Solvent recovery Gas separation Concentration of heat
sensitive biological macromolecules and proteins
INTRODUCTION TO MEMBRANE FILTRATION
http://cousemoses.wikispaces.com/Cubahttp://imperfectspirituality.com/2011/06/01/how-to-find-the-flow/flowing-waterfall/
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Membrane filtration can be accomplished with either dead end filtration or crossflow filtration.
Dead-end: Filter cake can form reducing filtration capacity.
Crossflow: Maintains more steady permeate flux and low pressure.
TWO MAIN TYPES OF FILTRATION
Figure: Created by Group 7
Figure: Created by Group 7
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PRESSURE-DRIVEN MEMBRANE SEPARATION
http://www.miniporeuf.com/channel.asp?id=26
• Reverse Osmosis
• Nanofiltration• Ultrafiltration• Microfiltration
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Employs tightest membranes for liquid separation. Only allows small water-soluble ions to go through
membrane along with water.
REVERSE OSMOSIS
www.degremont-technologies.com/dgtech.php?article458
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Removes multivalent ions and small molecules in nanometer range like sulfate ions, and sugars.
The most common type used for nanofiltration is the spiral membrane.
NANOFILTRATION
http://www.geaprocess.co.uk/gpuk/cmsdoc.nsf/webdoc/webb8uefdg
http://www.watertechtrading.com/purification-of-water/water-filtration/membrane-filtration/nano-filtration
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Used to retain relatively large dissolved materials like proteins and starches.
Ultrafiltration membranes are typically classified by their ability to retain component specific sizes.
ULTRAFILTRATION
http://www.answers.com/topic/reverse-osmosis
http://www.aquasource-membrane.com/-ultrafiltration-filtration-.html
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Suspended solids and large colloids are rejected, while dissolved solids and macromolecules pass through
Operate at low pressures of 10 psi or less.
MICROFILTRATION
http://www.geafiltration.com/library/enzyme_cell_separation.asp
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• Fabrication• Desired
Properties• Classification
s
MEMBRANE MATERIALS STRUCTURE AND
MORPHOLOGY
http://www.hidenisochema.com/application_industries/membrane-materials/
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Membranes are fabricated from variety of materials Made of Inorganic and organic materials Metals, polymers, and ceramics are used for different
applications based on their properties
FABRICATION OF MEMBRANES
http://icd.uni-stuttgart.de/?p=6947
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Ceramic and Metals used for aggressive media
Suitable for high temperature operations, acids, and strong solvent
CERAMICS AND METALS
http://www.made-in-china.com/showroom/ceramfil/product-detailNbcQIEdjLYhC/China-Ceramic-Membrane-Filter-CMF-Series-.html
http://www.directindustry.com/prod/purolator/stainless-steel-filter-cartridges-liquids-22202-884563.html
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Polymers are utilized most because of their price and versatility
Polymer membranes are typically made up of a thin layer of polymer on a porous backing, creating a material with high permeability, selectivity, mechanical strength, and chemical stability
POLYMERS
http://revision4gcses.wordpress.com/science/chemistry-2/polymers/
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Desired properties of membranes include:
High porosity Narrow pore size
distribution Sharp MWCO High mechanical strength Flexible High pH Chemical stability Surface properties Low fouling Low cost
DESIRED PROPERTIES
https://www.millipore.com/membrane/flx4/filter_properties_hm
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Membranes are classified according to structure, morphology, and application
Two classifications of membranes Symmetric membranes Asymmetric membranes
Composite membranes
CLASSIFICATION
http://research.che.tamu.edu/groups/Seminario/index-1.html
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Very few commercially available membranes are symmetric throughout their thickness
Some examples include: Polytetrafluoroethylene Polyethylene Polypropylene
SYMMETRIC MEMBRANES
http://ckj.oxfordjournals.org/content/3/suppl_1/i36/F2.expansion
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Include most of the commercially available membranes
Have either a thin microporous or dense permselective layer supported by a more-open porous substrate
The membrane may by integrally skinned, formed in a single operation, or by separate steps
An example of an asymmetric membrane is cellulose RO membrane, where both layers are made up of cellulose acetate.
ASYMMETRIC MEMBRANES
http://what-when-how.com/nanoscience-and-nanotechnology/nanofiltration-separations-part-1-nanotechnology/
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A composite membrane is a subset of asymmetric membranes
The skin layer and support layer are made up of different polymers based on the individual properties
The skin layer determines separation performance
Support layer determines mechanical stability
An example of a composite membrane is a polymide RO membrane which is made up of a thin polyamide permselective skin on a polysulfone UF support.
COMPOSITE MEMBRANES
http://www.ogj.com/articles/print/volume-94/issue-48/in-this-issue/production/membranes-solve-north-sea-waterflood-sulfate-problems.html
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• Cassette• Cartridge• Spiral
Wound
MEMBRANE MODULE DESIGN
Source: http://4.bp.blogspot.com/-Om7fiMFT42A/Tq4RXJWvfNI/AAAAAAAAFfg/RAxOua20zR8/s1600/2-12-idealfluidflow.008.png
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Cassette membranes are used for UF and MF.
The membrane filtrates the fluid, while the gaskets are used to separate the permeate, feed, and retentate streams.
Spacers introduce turbulence, which increases mixing and prevents the formation of a gel layer.
However, spacers are sometimes prone to particulate clogging, and can be difficult to clean.
CASSETTE
Source: "Understand the Basics of Membrane Filtration." Wang, Hua. Hongyi, Zhou. GE Global Research.
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INDUSTRIAL/LARGE-SCALE CASSETTE MODULE
Source: http://microclearmembrane.com/wp-content/themes/microclear_v0.1/img/products_photo_1.jpg
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Utilizes laminar flow for MF, UF, or NF.
Composed of a large number of hollow-fiber membranes in a cylindrical housing with permeate ports and end caps.
Has a very high packing density, therefore has a high surface area to volume ratio, making this particular filter ideal for product recovery.
CARTRIDGE
Source: "Understand the Basics of Membrane Filtration." Wang, Hua. Hongyi, Zhou. GE Global Research.
Source: http://ecx.images-amazon.com/images/I/41zayl%2BuLzL._SY300_.jpg
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Spiral Wound are used predominantly for RO.
They are composed of a multi-layered assemble of flat sheet membranes, and spacer screens.
These components are all rolled around a perforated tube, which seals the membrane and spacer layers on three sides.
SPIRAL WOUND
Source: "Understand the Basics of Membrane Filtration." Wang, Hua. Hongyi, Zhou. GE Global Research.
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They are built to have a high packing density by utilizing thin spacer screens.
Industrially, large-scale operations use these RO modules connected in parallel with one another.
SPIRAL WOUND MODULE USED FOR RO
Source: http://upload.wikimedia.org/wikipedia/commons/c/cf/Reverse_osmosis_membrane_coil.jpg
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>> % Rc: cake resistance >> % r: specific cake
resistance >> % Vs: volume of cake >> % Am: area of membrane >> >> %Plot of Rc vs. r (Vs =
0.001 m^3, Am = .01 m^2) >> r = linspace(0,10);>> Vs =
0.001;>> Am = .01; >> Rc = r*Vs/Am; >> plot(r,Rc,'-') >> legend('Vs and Am
constant') >> title('Plot of Rc vs. r') >> xlabel('r (m^-2)') >> ylabel('Rc (m^-1)')
PLOT OF CAKE RESISTANCE VS. SPECIFIC RESISTANCE WITH THE AREA OF THE MEMBRANE AND CAKE VOLUME HELD
CONSTANT
Figure: Created by Group 7
Source for Filtration equation: http://en.wikipedia.org/wiki/Microfiltration
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>> % Rc: cake resistance >> % r: specific cake resistance
>> % Vs: volume of cake >> % Am: area of membrane >> >> %Plot of Rc vs. Vs (r = 5 m^-2, Am = .01 m^2)
>> r = 5; >> Am = .01; >> Vs = linspace(1e-6,1,400); >> Rc = r*Vs/Am; >> plot(Vs,Rc,'-') >> legend('r and Am constant')
>> title('Plot of Rc vs. Vs') >> xlabel('Vs (m^-3)') >> ylabel('Rc (m^-1)')
PLOT OF CAKE RESISTANCE VS. CAKE VOLUME WITH THE AREA OF THE MEMBRANE AND SPECIFIC RESISTANCE HELD CONSTANT
Figure: Created by Group 7
Source for Filtration equation: http://en.wikipedia.org/wiki/Microfiltration
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>> % Rc: cake resistance >> % r: specific cake resistance
>> % Vs: volume of cake >> % Am: area of membrane >> >> %Plot of Rc vs. Am (r = 5 m^-2, Vs = .001 m^3)
>> Am = linspace(.0001,1,400);
>> r = 5;>> Vs = .001; >> Rc = r*Vs./Am; >> plot(Am,Rc) >> title('Plot of Rc vs Am') >> legend('r and Vs held constant')
>> xlabel('Am (m^2)') >> ylabel('Rc (m^-1)')
PLOT OF CAKE RESISTANCE VS. AREA OF THE MEMBRANE WITH THE SPECIFIC RESISTANCE
AND CAKE VOLUME HELD CONSTANT
Figure: Created by Group 7
Source for Filtration equation: http://en.wikipedia.org/wiki/Microfiltration
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•Desalinization using RO•Industrial water treatment•Biopharmaceutical manufacturing•Clarification steps in cellulosic ethanol production
COMMON MEMBRANE
APPLICATIONS
Picture: http://www.directindustry.com/prod/aqua-aerobic-systems-inc/membrane-bioreactors-mbr-wastewater-treatment-89335-876873.html
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Cost-effective Produce clean water from seawater in regions with limited
access to fresh water Removes salts, organic substances, algae, bacteria, and
suspended particles
DESALINATION FOR REVERSE OSMOSIS
Picture: "Understand the Basics of Membrane Filtration." Wang, Hua. Hongyi, Zhou. GE Global Research.
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Boiler feed water Cooling tower
water Process water in
many industries
INDUSTRIAL WATER TREATMENT
High purity water needed for:
Picture: http://en.wikipedia.org/wiki/Cooling_tower
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Conventional Treatment
MEMBRANE FILTRATION TECHNOLOGY MINIMIZES LAND, CONSTRUCTION, AND OPERATING COSTS:
Picture: "Understand the Basics of Membrane Filtration." Wang, Hua. Hongyi, Zhou. GE Global Research.
Membrane Treatment
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INDUSTRIAL MICROFILTRATION USES
Picture: http://bioprocessh2o.com/home/solutions/modular-containerized-mbr/
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For biological products: Recovery Purification Concentration
BIOPHARMACEUTICAL MANUFACTURING
Picture: "Understand the Basics of Membrane Filtration." Wang, Hua. Hongyi, Zhou. GE Global Research.
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Used for: Buffer exchange Final product
concentration Virus filtration
ULTRAFILTRATION
Picture: Created by Group 7
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CELLULOSIC ETHANOL PRODUCTION
Source: http://www.geafiltration.com/applications/membrane_filtration_ethanol.asp
Clarification of the pretreated liquor prior to hydrolysis
Clarification of the hydrolyzate stream prior to fermentation
Concentration fermentation pre-cursors
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CELLULOSIC ETHANOL PRODUCTION: CLARIFICATION USES
Picture: http://www.sciencedirect.com/science/article/pii/S0961953410003107
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Membrane filtration has lots of applications!
Several types of driving forces for membrane filtration: Pressure Difference Concentration Difference Temperature Difference
Used in many industrial processes: Desalination Wastewater and process water
treatment Biopharmaceutical
applications
CONCLUSION
Different types of membranes can be applied to various applications based on particle size: Reverse Osmosis (Smallest
constituent) Nanofiltration Ultrafiltration Microfiltration (Largest
constituent)
http://en.wikipedia.org/wiki/Filtration
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• Add a chemical to the solution being filtered to make membrane more durable
• Combine multiple driving forces
• Introduce turbulent flow to prevent clotting
SUGGESTED WORK FOR IMPROVEMENTS
http://ezial.com.au/Systems/SystemImprovements/tabid/115/language/en-GB/Default.aspx