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BIOSEPARATION
TECHNOLOGY
MK Mekanisasi Pertanian
Why Separation?
MOTIVASI PEMISAHAN
• Pemurnian.
Hal yang perlu diperhatikan: temperatur yang tinggi
menyebabkan dekomposisi beberapa komponen
• Pemindahan komponen yang tidak diinginkan.
Hal yang perlu diperhatikan: kehilangan komponen
yang berharga
• Recovery: untuk proses berikutnya
• Pemisahan padatan
Seaparation in Food Industries
Some Methods to Separate a Product
by Bioseparation
UNIT
OPERATION IN
BIOSEPARATION
Separasi mekanik
• Sedimentasi
• Separasi Sentrifugal
• Filtrasi
• Penyaringan
Gaya yang bekerja pada separasi mekanik:
gravitasi, sentrifugal dan tekanan
Kecepatan pergerakan partikel dalam Fluida
Kecepatan partikel tergantung pada:
ukuran, densitas dan bentuk partikel
serta sifat-sifat fluida.
Gaya yang berpengaruh: gaya eksternal
yang bekerja dan drag force yang
menahan gerakan.
FD FB
FG
SEDIMENTASI
• Sedimentasi gravitasi
• Flotasi
• Sedimentasi partikel dalam gas
• Pemisahan dengan kombinasi gaya
GRAVITATIONAL SEDIMENTATION
• Sedimentation uses gravitational forces to separate
particulate material from fluid streams.
• The particles are usually solid, but they can be small liquid
droplets, and the fluid can be either a liquid or a gas.
• Sedimentation is very often used in the food industry for
separating dirt and debris from incoming raw material,
crystals from their mother liquor and dust or product
particles from air streams.
Thickener kontinyu
Clear fluid
overflow
Clear fluid
Transition zone
Thickened
compression zone
Free settling
zone
Slow revolving
rake
Thickened
sludge
underflow
PERALATAN SEDIMENTASI
Cyclone
• Sering digunakan memisahkan aliran udara dari partikel-partikel dengan diameter sekitar 10 m atau lebih dan juga digunakan untuk memisahkan partikel dari cairan
• Bentuk cyclone bagian atas: silinder vertikal udara saratpartikel membentuk spiral menciptakan gaya sentrifugalsehingga partikel ke bagian dinding
• Gaya gravitasi mempercepat
pemisahan
CENTRIFUGAL SEPARATION
• Sedimentation process may be very slow because the specific
gravities of the components may not be very different, or
because of forces holding the components in association, for
example as occur in emulsions.
• For example, if whole milk is allowed to stand, the cream will
rise to the top and there is eventually a clean separation between
the cream and the skim milk.
• However, this takes a long time, of the order of one day, and so
it is suitable, perhaps, for the farm kitchen but not for the
factory.
• Hence, much greater forces can be obtained by introducing
centrifugal action, in a centrifuge.
A centrifuge uses centrifugal force to separate liquids/solid from liquid.
CENTRIFUGAL SEPARATION
Working principle
APPLICATIONS
Separating fat from milk
Cleaning dust from air
De-watering or de-oiling of food
DISTILLATION
We owe a great debt to the Arabian alchemist (and physician) Ibn Sina -
also known as Avicenna, who lived 980 - 1037 AD, since he was the first
one to perfect steam distillation - and his process was so good that it
stayed unchanged for a couple of hundred years.
Principles
• Distillation is a method of separating mixtures based
on differences in their boiling points.
APPLICATIONS
Production of essential oil
Alcohol purification
Sea water distilation
Petroleum refineries
FILTRATION
• Filtration is the separation of solids from liquids, by
causing the mixture to flow through fine pores which are
small enough to stop the solid particles but large enough to
allow the liquid to pass.
• The fine apertures necessary for filtration are provided by
fabric filter cloths, by meshes and screens of plastics or
metals, or by beds of solid particles. An advance filtration
for fine materials uses many types of membrane
FILTRATION EQUIPMENTS
Plate & frame press
Rotary vacuum filters
Centrifugal filters
MEMBRANE TECHNOLOGY
An advance type of filtration
Early membrane investigators experimented with
every type of diaphragm available to them, such as
bladders of pigs, cattle or fish and sausage casin
made of animal gut.
Later, collodion (nitrocellulose) membranes were
preferred because they could be made
reproducibly.
Types of Membrane
MEMBRANE PORE SIZE
APPLICATIONS
• Water purifications
• Separations of amino acids
• Gas separations