MEMBRANE…..?
“Barrier which separates 2 phases & restricts transport of various
molecules in a selective manner”.
Driven by
• Pressure
• Concentration
• Temperature
• Electrical potential
Can be
Thick/Thin
Liquid/Solid
Symmetric/Asymmetric
Natural/Synthetic
Neutral/Charged
•MEMBRANE FILTRATION
Uses a physical barrier
Porous membrane or filter,
To separate particles in a fluid.
HISTORY:• IN 1748 - ABBE JEAN-ANTOINE NOLLET; French physicist
separated degassed alcohol using pig’s bladder.
• 1824, RENE-JOACHIM-HENRI DUTROCHET, French
physiologist introduced “osmosis”: movement of water through a
biological membrane
• 1861- THOMAS GRAHAM (FATHER OF MODERN DIALYSIS): coined
“dialysis “- separated dissolved substances based on mol.wt.,
& concentration.
• 1865 – MORITZ TRAUBE invented first artificial membrane using
Copper Ferro cyanide precipitates
• 1875- WILHELM FRIEDRICH PHILIPP PFERRER: Made the membranes
to withstand operational pressures
WORKING MECHANISM:
• MEMBRANE PROCESS: The feed stream is divided into two streams:
• Retentate (concentrate) stream
• Permeate stream
• Either the concentrate or permeate stream is the product of our interest.
•REPRESENTATION OF MEMBRANE SEPARATION
Driving Force
Feed
MEM
BRA
NE
Permeate
CLASSIFICATION OF
MEMBRANES
Pressure driven
Electrically driven
Pressure
driven
Ultra filtration
Micro
filtration
Reverse osmosis
Nano filtration
Concentration driven
Pervaporation
Dialysis
Gas separatio
n
Electrically driven
Mic
rofi
ltra
tion
Low pressure driven
(2 bar)
Membrane with an open structure
Allows-Dissolved particles
Rejects-Undissolved particles
APPLICATIONS•Bacterial reduction
•Fat removal in milk
•Whey as well as protein and casein standardisation
•Removal of casein from whey protein
ULTRA FILTRATION
Medium pressure driven
(1-10 bar)
Membrane with a medium open structure
Allows-Most dissolved , some undissolved particles
Rejects-Large particles
APPLICATIONS
•NANO FILTRATIONMedium to high pressure
driven
(5-40 bar)
Membrane with slightly more open structure
Allows-Monovalent ions
Rejects-Divalent ions
APPLICATIONS
•REVERSE OSMOSIS
High pressure driven
(10-100 bar)
Dense membrane
Allows only water
REVERSE OSMOSIS
APPLICATIONS
MEMBRANE CHARACTERISTICS
• Pore size:
• Microfiltration - 0.1 – 5µm
• Ultrafiltration - 0.01-0.1 μm
• Nano filtration - 0.001-0.01 μm
• Reverse osmosis- 0.0001 – 0.001 μm
• Temperature resistant <40ºC & 70-80ºC
• Pressure resistant
•ELECTRODIALYSIS• Semi permeable membrane
• Allows either positive or negative charged ions
• Under the influence of electricity
APPLICATIONS
Demineralization of dairy products
Demineralization of whey
Desalination of cheese whey
MEMBRANE FOULING
• Process where solute or particles deposit
• Onto a membrane surface or into membrane pores
• Degrades the membrane's performance.
Pre-treatment of the feed
solution
Membrane properties
.
Cleaning
a. Narrow pore size distributionb. Hydrophilic membranes
a. Heat treatmentb. pH adjustmentc. Chlorination
a. Hydraulic cleaning
b. Mechanical cleaning
c. Chemical cleaning
METHODS TO REDUCE FOULING
APPLICATIONS IN
DAIRY INDUSTRY
Extending shelf life
Desalting or demineralization
Fat
processing
Protein
processingCheese
industry
WASTE WATER TREATMENT
Whey processing
Lactose free milkHigh calcium
low fat milk Non fat yoghurt
High protein low fat
ice-creamLow lactose low fat
milkWhey based
beverage
Lactose free ice-cream
CONCLUSION
• Alternatives to conventional processing method.
• Cold pasteurization method
• Create products, ingredients with favorable characteristics
• Without the addition of chemicals, with low energy use.
• A very good technology for wastewater treatment.
FUTURE TRENDS
• Produce even higher-quality products at reasonable costs.
• Can apply ‘Reduce, reuse, recycle’
• Reuse of process waste water for water efficiency and security
improvement.
• Recycle is the process of converting waste materials into useful end
products
REFERENCE• Trevor Britz, Richard K. Robinson, Advanced dairy science and
Technology, Black well publishers Pg. no57-61
• By P. Walstra, Dairy technology: principles of milk properties and
processes ,Eastern hemisphere distribution, Pg. no 116-118
• Jelem p 1993,’’Pressure driven membrane processes; principles
definitions” New applications of Membrane processes, Brussels
Belgium:IDF pg. no7-14
• Www.Dairyprocessinghandbook.Com/chapter/membrane-technology
• JOURNAL OF FOOD RESEARCH AND TECHNOLOGY journal
homepage: www.Jakraya.Com/journa/jfrt