The document summarizes the process of sugar production from sugar beets. Key steps include harvesting beets from fields, cleaning and slicing beets, extracting sugar through diffusion with hot water, purifying juice through lime and carbonation, concentrating juice in evaporators, crystallizing sugar and separating it from molasses through centrifugation, and further processing molasses to extract remaining sugar. The finished sugar is then packaged, stored, and shipped for export.

2. SUGAR PROCESSING
FROM SUGAR BEET
Presented by: Ayaz Ahmad
Class no: 258
Subject: Sugar Technology
Teacher: Dr. Ihsan Mabood Qazi

3. Sugar beet
 Scientific name: Beta vulgaris L.
 Family: Amaranthaceae
 Habitat: temperate zone
 Irrigation: 6-7 (sprinkle) and 5-6 (flood)
 Soil: Sandy loam
 Average weight: 0.5-1.0 kg
 Leaves: broad, height 35cm and grow from the crown of beet
 Diseases: Aphanomyces Root Rot, Beet Curly Top etc.
 Top five producer: France, USA, Germany, Russia and
Turkey.

4. COMPOSITION
75-78%
water
17-20%
sugar
4-5%
Non-sugars

5. FROM FIELD TO FACTORY
 Sowing is done from April-May
 Harvesting start in September
 Harvesting is done mechanically
 Harvested beets are bring to factory through trucks or
lorries
 The beets are weighed by weighbridge
 Sample are taken to determine sugar-content
 The beets are unloaded:
1.dry-unloading (beets are stored in open air silos) and
2.wet-unloading (beets are washed in lorry through water jet
and transferred to washing station)

7. CLEANING OF BEETS
 Beets from silos or wet-unloading are passed to the washing
station through conveyer belt
 In route to the production process, stones and grass are
removed in a series of stone and grass catchers
 First they enter into the revolving drum where under a
shower of water the beets rubbed against each other
dislodging the soil
 The water flow, floats the beets which exit the drum
 The stones remain behind and collected in separate bucket
along the edge
 A screw conveyer moves the beets to the transfer system
which brings them into the slicing machine

8. SLICING
 The sugar beets are bring into the slicing machines where
very sharp knives cut them into long noodle-like pieces
called cossettes
 This makes more surface area for extraction of sugar
 Emerging from the slicing machines, the cossettes fall onto
a conveyor belt to be weighed and fed into the diffusion
system

9. DIFFUSION
 Sugar is extracted from the beet by diffusing it out with hot
water up to 70oC
 The beets are fed into the bottom of the diffuser and water is
entered from the top of diffuser
 Through the process of osmosis sugar is extracted from beet
slices into hot water called raw juice (contain 14% sugar)
 The remaining slices are called pulp ( up to 2% sugar) and are
send for further processing

10. PULP DRYER
 The wet pulp (90-92% water) from the diffuser is sent to pulp
presses
 The pulp presses squeeze the pulp in order to remove as much
water as possible
 then it is called pressed pulp (72-78% water) and is either sold
as livestock feed or sent to the dryer for further processing
 The water pressed out of the pulp is sent back to the diffuser to
recover the sugar in it
 The pulp dryers are direct fired by oil, gas or coal and dry the
pulp to 12% moisture
 Pressed pulp is sold for short term use while pellets store for
longer periods, but both are used for livestock feed

12. LIME KILN
 In sugar factory the lime kiln supplies the burned lime and
carbon dioxide for the purification processes
 Limestone (calcium carbonate) is heated to 1093OC in a
lime kiln using hard coal or natural gas
 The heating process releases carbon dioxide from the
limestone reducing the calcium carbonate to calcium oxide
 The calcium oxide (burned lime) is then mixed with sweet
water to form milk of lime in a lime slacker

13. PURIFICATION AND FILTERATION
PROCESSES
 Before sugar can be produced in a white crystalline form it
is necessary to remove non-sugars present in the juice
 lime and CO2 are added to the juice causing non-sugars to
be precipitated out of the solution
 Lime and CO2 are added in the following ways

14.  Raw juice having pH 5.5-6.0
 Pre heated and then slack lime and CO2 is added to it
raising pH between 8.8-9.0 and temperature between
75-80OC
 First carbonation is done and lime is added to raise the pH
between 11.0-11.5 and temperature between 85-88OC
 The resulting juice flows to a clarifier where the
precipitated calcium carbonate formed in first carbonation
is settled out
 The clear juice is filtered, heated and send for second
carbonation while the defecation lime left behind in the
bottom

15.  The defecation removed and fed to vacuum drum filters
where it is washed to recover the sugar left in it
 The washed defecat has about 1% of the sugar from the
beets in it and is sent to a lime pond
 The washed water with the recovered sugar is called
"sweet water" and is sent to the lime house to be mixed
with the burned lime

16.  In the second carbonation system CO2 is used to form
calcium carbonate precipitate
( pH 8.7-8.8 & temp 95-100OC)
 Juice is stored in collection tank, then filtered and again
heated
( pH 8.5-9.0 & temp 74-80OC)
 Sulfitation is done along with the addition of slack lime
( pH 7.0-7.5 & temp 90-100OC) and resulting thin juice is
send to evaporators

17. EVAPORATION PROCESS
 The thin juice is a sugar solution containing
approximately 14% sugar and 1% non-sugars
 The juice is concentrated boiling off water from the
solution in large vessels known as evaporators
 The evaporation station consists of 4 to 6 evaporator
bodies that contain tubes
 Steam is fed to the outside of the tubes and the juice is
on the inside of the tubes

18.  The heat transfers from the steam to the juice
 The water evaporated in one evaporator becomes the steam
feeding the next evaporator while the juice travels from one
effect to the next
 The thin juice enters the evaporators at 13 to 15% solids and
leaves the station at 60% solids and is called thick juice

19. CRYSTALLIZATION AND
SEPARATION
 Thick juice is send to high melting machine where high and low
sugars are dissolved in it through heating and agitation
 The juice is then heated, filtered and further concentrated
through the "concentrator" to 70 to 75% solids
 This is then called standard liquor and is fed to the white pan
where white sugar is crystallized from solution
 Finely ground sugar is used to "seed" the pan
 More and more water is evaporated forcing more sugar to
crystallize
 The solution is concentrated to 92% solids and consists of sugar
crystal surrounded by syrup of sugar-water and this is call white
massecuite.

20.  The massecuite is dropped into a mixer that then feeds the
white centrifugals
 The white centrifugals separate the sugar crystals from the
syrup in the massecuite by spinning the sugar against a
screen while the syrup spins through the screen
 Hot water is used to wash the residual syrup from the
crystal
 The white sugar is then conveyed to the granulator for
further drying and cooling
 The finished sugar is then shifted to the bulk sugar bins for
storage

21. HIGH RAW SYSTEM
 White centrifugal produce two type of syrup: 1.the high wash
is higher purity syrup that is recycled to the high melter 2.the
high green is the lower purity syrup
 It is sent to the high raw vacuum pan for processing
 Here again, seed crystals and evaporation are used to remove
sugar from the syrup solution
 The high raw massecuite is sent to a mixer and then to
another set of centrifugals to separate the sugar crystal from
the syrup
 The sugar crystals made here are not a good enough quality so
they are sent to the high melter to be re-dissolved and re-
processed in the white pan

22. LOW RAW SYSTEM
 The syrup leaving the high raw centrifugals is called machine
syrup
 Lower in purity than high green syrup
 The machine syrup is sent to the low raw system that contains
one additional piece of equipment as compared to the high
raw system
 The low raw vacuum pan is used to crystallize sugar

23.  The low raw massecuite sent to a crystallizer where cold
water is used to continue the crystallization process for an
additional 48 hours
 The low raw massecuite send to the low raw mixer and
centrifugals where sugar crystals are separated from the
syrup called molasses
 The sugar crystals are sent to the high melter for re-
processing

24. MOLASSES DESUGARIZATION
 The molasses is about 50% sugar by weight
 About 10-15% of the sugar from the beets leaves the sugar
factory in molasses
 The molasses is sent to the molasses desugarization system
 This operation removes about 80% of the sugar in the
molasses
 The molasses is treated to remove some non-sugars (Ca, Mg
and suspended solids) that will cause processing problems in
the separation process

25.  The molasses is softened by replacing non-sugars with
sodium and filtering the precipitates formed in the
reaction
 The pre-treatment process consists of dilution, heating,
soda ash addition (sodium source) and filtering
 The filtering process uses plate and frame filters to
squeeze the softened molasses through filter leaves, while
the precipitated non-sugars remain behind

26. SOFTENED MOLASSES SEPARATION
 The softened molasses is sent to the separation (ion
exclusion) process
 The columns are loaded with a resin that attracts certain
chemicals while letting other chemicals pass through
quickly
 This difference in travel time is used to separate the
molasses into a sugar fraction, a betaine fraction and a
residual molasses fraction

27. PACKAGING AND STORAGE OF
PRODUCT
 Dry sugar is stored in sugar silo which has air conditioning
 For the expedition sugar is packed in 50, 25 kg bags
 It can also be delivered unpacked in tanks
 Before packing, it is important that all sugar be cooled
below 45° C
 At higher temperatures it hardens in the bag or silo