Membrane Processing Technology; Microfiltration, ultrafiltration, nanofiltration

Membrane Processing Technology; Microfiltration, ultrafiltration, nanofiltration

1. Membrane processing

2. In 1752, J. AbbeNollet discovered the phenomenon
of osmosis.
History of membranes
ethanol
Water + ethanol
Semipermeable
membrane
Pig’s bladder
Driving force:
Osmotic pressure

3. Definition of a membrane
An intervening structure separating two
phases and/or acting as an active or
passive barrier to the transport of matter
between the phases adjacent to it.

4. SEPARATION CONTACTING
IMMOBILISATION
CONTROLLED RELEASE
Membranes
The heart
Membrane functions

5. Membrane structures
Symmetric
The structure and
transport properties
are identical over the
entire cross-section
The total thickness
determines the flux
Dialysis and
electrodialysis.

6. Micro pores
Support layer
(100μm)
Polymer 2
Skin layer(<1μm)
Polymer 1
Composite membrane

7. Ultrafiltration (UF)
a selective fractionation process
utilizing pressures up to 145 psi
(10 bar)
concentrate suspended solids
solutes of molecular weight
greater than 1,000
The permeate contains low
molecular-weight organic solutes
and salts

8. Nanofiltration (NF)
a special process selected when
RO and UF are not the ideal
choice for separation
perform separation applications
(demineralization color removal
desalination )
the permeat contains monovalent
ions and low molecular-weight
organic solutions

9. Microfiltration (MF)
low pressure cross-flow
membrane process
separating colloidal and
suspended particles
in the range of 0.05-10
microns
used for fermentation
broth clarification biomass
clarification recovery

10. Reverse Osmosis (RO)
high pressure energy-efficient
technique
dewatering process streams
concentrating low-molecular-
weight substances in solution
(purifying wastewater)
concentrate all dissolved and
suspended solids
permeate contains a very low
concentration of dissolved solids
widely used in the desalination
of seawater
RO

11. Membrane separations are applied
concentration (removal of a diluting solvent such
as water)
purification (separation of contaminants)
fractionation (resolution into two or more
component substances)

12. applications of micro-filtration
•cold sterilization of beverages
•clarification of fruit juices, beers and wines
•continuous fermentation
•separation of oil-water emulsions
•wastewater treatment
•beer, milk, whey, brine, etc

13. MF---cold sterilization
Bactocatch
R
from Tetra Alcross (Pully
Switzerland) www.tetrapak.com
Ceramic
membranes

14. Applications of ultra-filtration
•concentration of milk
•recovery of whey proteins
•recovery of potato
starch and proteins
•concentration of egg
•clarification of fruit juices
and alcoholic beverages
Wine
clarification
Nearly 1000
systems
installed
wastewater
treatment

15. UF-Whey protein concentrate manufacture

16. •removal of micro-pollutants
•water softening
•waste water treatment.
Main application of nano-filtration

17. Reverse osmosis
Integrated or composite
membranes;
Pore size<2 nm
Pressure 30～60 bar
Solution-diffusion
mechanism
RO
Desalination
Production of ultra
purewater
Concentration of juice
and milk
Application

18. Equipment of our campus

21. Plant visit of enzyme mill
Concentration of the enzyme

22. Advantages
No phase change;
Energy efficient;
A higher quality product;
Environmentally friendly;
Easy to scale-up
Advantages and limitations of
membrane technologies
Limitations
Long-term reliability not
proven;
Excessive pretreatment;
Concentration polarization
and membrane fouling;
Replacement of
membranes;