3. INTRODUCTION
Sugar
• General term indicating sweet carbohydrates
• Mono-, di- and poly-saccharides
• Obtained from plants, largely sugarcane & sugar
beet plant
• Pakistan 12th largest producer of sugar
• Per capita consumption of sugar is 25kg
• More than 81 sugar mills in Pakistan
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9. Material Handling and Storage
• Stored in cane yards
• Carried from cane yard to feeding area by
– hook/chain
– Cranes
– Reelings
– Conveyer belt
– Carry
– Huge suction truck
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16. CRUSHING
• Cane crushed to
break hard structure
• Cells containing juice
are ruptured
• No juice extracted
• Increase efficiency of
juice extraction
• Subjected to crusher
with corrugated
blades
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18. MILLING TANDEMS
• 3 roller mills
connected in series
– Top roller
– Feed roller
– Discharge roller
• 5-7 in number
• Extract the juice from
crushed cane
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22. USE OF BAGASSE
• Stored in bagasse storage
• Used as fuel to generate steam
• Steam used for
– Generating electricity
– Evaporation of juice before crystallization
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29. EVAPORATION
• Juice evaporated to obtain super saturated
solution
• Increase concentration of juice from 15ᴼ brix
to 65ᴼ brix
• Juice preheated to
around 107-110ᴼC
• Two types of evaporators
– Single effect evaporators
– Multiple effect evaporators
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31. CONT…
• Steam used to evaporate juice
• 1 liter steam to evaporate 4
liter juice
• Steam temperature 113-
130ᴼC at 1st pan and
55ᴼC at last pan
• Each subsequent vessel with
decreasing pressure
• Last pan being under almost a
total vacuum
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33. CRYSTALLIZATION
• Carried out in single effect high-vacuum boiling
pans
• Brix are increased from 65ᴼ to 75ᴼ by boiling at
60ᴼC
• Three stages of crystallization
– Nucleation
– Initiation
– elongation
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34. CONT…
• Massecuite
– mixture of crystals and mother
liquor (molasses) resulting from the
crystallization
• Transferred to crystallizer
at low temprature
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36. CENTRIFUGATION
• Separate sugar from molasses
• Centrifuge operates at 100-1800 rpm
• Molasses pass through perforations
• Sugar crystals are
washed with 85ᴼC water
• Raw sugar and molasses
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43. AFFINATION
• Mixture of raw sugar with high purity syrup
(85%) called magma
• Melts outermost layer of the raw sugar crystal at
50ᴼC
• Centrifugation to remove resulting syrup from
melting of the outer layer
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44. MELTING
• Affinated sugar dissolved
with hot condensate to
conc. of 72ᴼ brix
• Melted at 85ᴼC in Batch or
continuous melter
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45. PURIFICATION
• Remelt may contain some impurities and
colorants
• Liming
1. Partial 2. Complete
• Carbonization
• Colorants remover by decolorization
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47. EVAPORATION &
CRYSTALLIZATION
• Sugar syrup evaporated up to super saturation
• Crystallization
• Centrifugation to obtain refined sugar crystals
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48. DRYING AND STORAGE
• Bucket elevator on conveyer
• Hot air for drying
• Sieving
– Fine, medium and bold grains
• Storage in godowns
– Cool, dry, moisture and odor free
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49. PACKAGING
• Containers opaque, airtight, moisture/odor proof
• Glass canning jars or cans for liquid sugars
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50. RAW & REFINED SUGAR
• Raw sugar
• Obtained directly from sugarcane juice without
refining
• Most natural sugar
• Brown in color due to molasses
• Refined sugar
• Have white luster and transparent
• Bleached to remove color and other impurities
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51. FACTORS AFFECTING
SUGAR STORAGE
• Temperature
• Moisture
• Quality of sugar
• Light
• Grain size and distribution
• Compression
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