SUGAR MANUFACTURING PROCESS
In India the cane is harvested manually and harvested cane is supplied by the sugar cane
Grower’s through bullock-cart and trolley at factory main gate or factory cane purchasing
centre. After weighment of the cane it is unloaded on cane carrier by over head three motion
unloading cranes and truck-tripplers. The sugar cane is passed through set of cutter and the
fibrizers /shrudders to disintegrate sugar cane cells for efficient milling. The prepared cane
there passed through a set of milling tendem for the extraction of the juice by compression
methods. The juice extracted is strained and fine bagacillo particles separated from the juice
and return to milling tendem. After extraction of juice the remained residuals is called
bagasse and is conveyed by means of carriers and used as fuel to the boilers.
The extracted juice is weighted again through mars flow meter. Double Sulphitation Process
is followed for the manufacturing of the sugar. The raw juice is sent to juice heater and is
heated up to 700C before liming and sulphitation in a continuous juice sulphiter. Lime and
sulpher dioxide (SO2) are two major chemicals mixed with juice for clarification the juice. The
treated juice is again heated up to 1020C to 103 0C and to made to enter in a flash tank for the
removal of gases and air, before entering into a continuous clarifier where the settling of the
mud flocks takes place.
The clear juice is withdrawn from the upper region and sent for further processing while
accumulated mud is send to vacuum filter station where the mud solid particles are separated
and muddy juice return back in to raw juice.
The clarified juice from the clarifier is further heated to around 1150C in a plate type heat
exchange before entry into set of evaporators for thickening. Evaporators have consisted with
4 to 5 set bodies, which work under vacuum. The vapour from the 2nd effect is used to heat
the pan. The syrup of approximate 58 0Brix to 63 0Brix is further clarified by passing through a
continuous syrup sulphiter and pumps to pan supply tank at the pan floor.
A three or three and half boiling systems are followed with the use to true seeding methods
in the pans for complete exhaustion. The process of crystallization is initiated in the pans and
is completed in the crystallisers.
The Concentrated sulphated juice called syrup is boiled under vacuum with 25” Hg I pans
where the crystallization of the sugar takes place. The mixture of sugar crystal and mother
liquor is called massecuite which is dropped into the crystallisers where the further
crystallization takes place. The sugar crystal is separated from the mother liquors by passing
it through the centrifugals. The sugar discharge from the centrifugals is dried and cooled by
multi-tray hopper and conveyed to sugar grader. Sugar is screened accordingly to their
crystal size of L, M and S packed into 50/100 kg sugar bags. The mother liquor coming out
for centrifugal machines which called Molasses which is further boiled in Pan to further
crystallization of th e remaining sugar in the molasses. Molasses, bagasse and press mud are
the by-product of the sugar plant.