Sugar Production

The process adopted in the
manufacture of sugar is Double
Sulphitation Process.
Sugar Factory consists of the
following five main stations:
1. Mill House
2. Boiler House
3. Power House
4. Clarification and Evaporation
House
5. Boiling and Curing House
MILL HOUSE:
Mill house is the cane crushing unit
which consists of cane carrier, cane
cutter having cutting knives, milling
tandem, bagasse carrier and
conveyor. Cane feeding to the cane
carrier is done by unloaders and
feeder table. As the cane carrier
moves, the cane kicker evens out
cane load in the cane carrier and
then two sets of cane knives cut the
cane into small pieces. This process
of cane cutting is called 'cane
preparation. These cane pieces then,
pass through different mills and the
juice is extracted. The mills are
driven by D.C.motors. The residue
which comes out of the mill after
extraction of juice is called bagasse.
BOILER HOUSE:
Boiler generates steam by burning
the bagasse. The steam is used in
powerhouse, boiling house, curing
house. The steam required by the
Sulphitation process varies from 42 -
45 % on cane crushed per hour.
POWER HOUSE:
The high pressure steam generated
by the boiler is utilized for
production of power by the turbo-
alternators. The power produced is
used for captive needs and the
surplus power is exported to the
government grid. The low pressure
steam that comes out from the turbo
alternator is utilized for boiling the
extracted juice.
CLARIFICATION AND BOILING
HOUSE:
The juice extracted by the mills is
measured by juice flow system. The
measured juice is heated in juice
heater in two stages. First the juice
is heated by the vapours from fourth
and third bodies of evaporator in
different heaters. This heating is
called primary heating. The heated
juice is treated with milk of lime and
sulphur-di-oxide to coagulate
maximum impurities and sent for
secondary heating. The secondary
heating is done with vapours from
second body of evaporator and
vapours from the first body or
exhaust steam. The treated juice is
passed to clarifier, where in clear
juice is removed from the top and
settled mud at the bottom is
separated. To extract sugar from the
mud, it is taken to vacuum filter in
which juice and filter cake are
separated. Juice is taken back to
process and the mud is disposed as
solid waste. Clear juice from clarifier
is taken to evaporator for
evaporating its water content. First
body is heated by exhaust steam,
and other bodies by the vapours of
the previous body. The total water
evaporated in the evaporator is
75-80 % percent. The juice after
evaporation is called as syrup. This
syrup is normally of 60 % solids of
its total weight. The syrup is then
sulphited in syrup Sulphitation
tower.
BOILING AND CURING HOUSE:
Sulphited syrup is taken to pan floor
for making sugar crystal. Three
massecuites boiling systems is
normally adopted, in which, A, B and
C Massecuites are boiled. A-
massecuites is formed by boiling
syrup, sugar melt ,‘A’ light molasses
and on ‘B’-single cured sugar as
seed. This A-Massecuite is boiled
till it attains the required size of
sugar crystal and it is dropped into
crystallizers and cooled. After
exhaustion of sugar in solution, the
‘A’ massecuite is passed on to the
centrifugals for separating sugar
crystals from the massecuite. The
separated 'A' sugar is bagged after
drying. ‘A’-Light and ‘A’-Heavy
molasses are pumped to pan floor
and are used for making ‘A’- and ‘B’-
Massecuite respectively.
‘B’-Massecuite boiled in ‘B’ pans is
dropped into B- Crystallizers and
then it is cured in ‘B’-Centrifugal
machines. ‘B’-heavy molasses and
‘B’-single cured sugar are obtained
separately. ‘B’-single cured sugar is
used as seed for A massecuite. ‘B’-
heavy molasses is used for making
‘C’-Massecuite in C-pans. ‘C’-
Massecuite is dropped into ‘C’-
Crystallizers where it is cooled. ‘C’-
Massecuite is then taken to ‘C’-fore
worker centrifugal machines for
curing. Final molasses and ‘C’-single
cured sugar are obtained. 'C' Single
cured sugar is again cured in
another centrifugal machine in
which ‘C’-double cured sugar and
‘C’-light molasses are obtained. ‘C’-
light molasses are taken to pan floor
and is used in making ‘C’-
Massecuite. ‘C’-double cured sugar
is melted and is used in making 'A'
Massecuite.
Sugar discharged from 'A' Machine is
dropped on to grass hopper
conveyors. By passing hot air in
hoppers the sugar is dried and
taken to grader in which powder and
rori’s are separated. The required
grade sugar is bagged