Cane Sugar

CANE SUGAR

RAW MATERIAL

The sugar requirements of the world are supplied from 2 main sources . The sugar cane is one of them. Climatically sugar cane is a tropical plant. The sugar cane requires ; • High Temperature • Ample supply of water during the growing period. It has average 2- 10 meters lengths

The sugar production by 70 % on the world is supplied from sugar cane. There are two important reasons : • Cost of sugar production from sugar cane lower than sugar beet. • Sugar cane is harvested 2 times per years but sugar beet only one.

High Quality Cane Low Quality Cane Sugar Sugar Cane water in (100 kg 50 kg 40 kg cane sugar ) Sugar ratio in cane 22 % 17 % water Amount of gur in ( 100 10 kg 7 kg kg cane sugar ) The sugars are synthesised by the cane plant from water and atmospheric carbon dioxide.

The sugar process is divided Ø Harvesting Ø Entry or transportation of the sugar cane Ø Milling Ø Clarification Ø Evaporation Ø Crystallization Ø Separation Ø Refining Ø Drying Ø Storage

HARVESTING

When sugar cane is ready for harvesting it stands two to four metres tall. Farmers harvest their cane between June and December when rainfall is less frequent and the plant’s sugar content is at its highest. Traditionally, the cane has been burnt before harvesting to remove leaves, weeds and other trash which impede harvesting and milling. However it is now common for sugarcane to be harvested green rather than burnt.

SUGAR CANE HARVESTER SUGAR CANE HARVESTER

ENTRY OR TRANSPORTATION OF THE SUGAR CANE

•Sugar is obtained from the cane at mills located near centers of production. •The cane first goes through a washer, then is cut into small pieces by revolving knives. •After this step the small pieces are shredded. The shredder is a large powerful hammermill that shreds the cane into a fibrous material. The cells in the cane stalk containing the sugar juice are ruptured but no juice is extracted at this stage. •After this preparation, the juice from the sugar cane can be extracted.

MILLING

The shredded cane is fed through a series of crushing mills to extract the sugar rich juice, which is then pumped away for further processing. The remaining fibre is called bagasse. The crushers consist of two large grooved rollers mounted horizontally, and then one above of the others. On the upper roller heavy hydraulic pressure is maintained

SUGAR CANE MILL SUGAR CANE MILL

Bagasse Fired Boiler BAGASSE FİRED BOİLER

CLARIFICATION

The limed juice enters a gravitational settling tank: a clarifier. The juice travels through the clarifier at a very low superficial velocity so that the solids settle out and clear juice exits. The mud from the clarifier still contains valuable sugar so it is filtered on rotary vacuum filters where the residual juice is extracted and the mud can be washed before discharge, producing a sweet water . The juice and the sweet water are returned to process. Brix 15°- 18° Purity 80-87 Reducing sugars 0.4- 1.0%. Ash 0.4-0.7%. CaO mgms/litre 600-800 P2O5 mgms/litre 60-300 N2 0.03-0.04% pH 5.2-5.4

CANE JUICE CLARIFIER CANE JUICE CLARIFIER

Ash and Water Clarifier ASH AND WATER CLARİFİER

EVAPORATION

The clarified juice is concentrated to syrup by boiling off excess water in a series of connected vessels. Under automatically controlled conditions in the evaporator station, each subsequent vessel operates under decreasing pressure with the last one being under almost a total vacuum. After this step the syrup is ready to go to the high- vacuum boiling pans.

EVAPORATOR EVAPORATOR

CRYSTALLIZATION

Concentration of the syrup from the evaporator is continued in vacuum pans. Very small seed crystals are introduced to the concentrating syrup and these begin to grow in size. When the crystals reach the required size, the mixture of crystals and syrup is discharged from the pan.

Continuous Vertical Crystallizer CONTİNUOUS VERTİCAL CRYSTALLİZER

SEPARATION

The sugar crystals are separated from the syrup in centrifugal machines that have an action similar to a spin- dryer. After leaving the centrifugals, the moist raw sugar is tumble dried in a stream of air and transferred to bulk storage bins. The separated syrup is reboiled and further sugar is crystallized. After three boilings no further sugar can be economically removed. The residual sugar is called molasses.

SEPARATOR SEPARATOR

REFINING

The purpose of the refinery is to remove impurities from sugar crystals. The refinery accepts raw sugar as its feed material. The sugar is dissolved (melted) and the colour is removed by various clarification processes. The final refining steps include melting the brown or raw sugar, decoloring by passing through carbon filters, recrystallizing in vacuum boiling pans, and drying by centrifuging.

CARBON FILTER

DRYING

The deterioration of sugar is retarded and the loss in test is reduced if the moisture content of the sugar is reduced. The water content of raw sugar is generally within the range 0.5-2%. With a dryer, this may be reduced to between 0.2 and 0.5%. This gives a saving in two directions: • The sugar keeps better • The polarisation and the titre increase immediately, in proportion to the water removed, and the financial gain so realised is much greater than loss of weight due to the water evaporated.

Sugar Dryer and Cooler SUGAR DRYER AND COOLER

STORAGE

The finished product is stored in large concrete or steel silos. It is shipped in bulk, big bags or 25 – 50 kg bags is used to industrial customers or packed in consumer-size packages to retailers. The dried sugar must be handled with caution, as sugar dust explosions are possible.

CONTROL POİNTS

Sample Determinations to be Number of made determination in 24 hours SUGAR CANE a)Cane fiber Fiber 1 b)Cane juices Brix 24 Sucrose 2 First mill juice Purity 2 Alkalinity Acidity 2 Brix 24 Sucrose 2 Purity 2 Mixed juice Reducing sugar 2 Ash 1 Alkalinity Acidity 2

Brix 24 Sucrose 2 Last mill juice Purity 2 Alkalinity Acidity 2 Brix 24 Sucrose 2 Clarified juice Purity 2 Alkalinity 2 c)Syrup Brix 2 Sucrose 2 Purity 2 Reducing sugar 2 Ash 2 Acidity 2 Sucrose 24 BAGASSE Fiber 2 Dry substance 12

FILTER-PRESS WORK

Brix 24 a)Juices Sucrose 2 Purity 2 Alkalinity 2 b)Filter-press cake Sucrose 2 Water 2 SUGAR Sucrose 2 a)Sugar Reducing sugar 2 Water 2 Ash 2

b)Fill mass Brix Each strike Sucrose Each strike Purity Each strike c)Molasses First molasses Brix Each strike Sucrose Each strike Purity Each strike Clerget Each strike Exhausted molasses Brix Each strike Sucrose Each strike Purity Each strike Clerget Each strike

PROPERTIES OF FINISHED PRODUCT

From ‘’TS 861’’ Properties White Sugar Class 2 (refined) Class 2 (crystal) Crystal sugar Cutting sugar Crystal sugar Cutting sugar Polar sugar,Z,min 99,7 99,7 99,7 99,7 Invert 0,04 0,04 0,04 0,04 sugar,%,(w/w),max Conductivity 0,0108 0,0108 0,027 0,027 ash,%,(w/w),max Color type (Crystal 4 4 9 9 color),Braunschweig score,max Solution color, 22,5 22,5 45 45 ICUMSA units,max Loss of 0,06 0,1 0,06 0,1 drying,%,(w/w),max Sulfur dioxide 15 15 15 15 (SO2),mg/kg,max Arsenic(As), 1 1 1 1 mg/kg,max Copper(Cu), 2 2 2 2 mg/kg,max Lead(Pb), mg/kg,max 0,5 0,5 0,5 0,5 Starch and None None None None others,%,(w/w),max material None None None None

TECHNOLOGY OF CANE SUGAR

THE MİLLİNG PROCESS OCCURS İN TWO STEPS

1. Breaking the hard structure of the cane 2.Grinding the cane •-knives •The crushed cane •-shredders multiple sets of •-crushers three roller mill are •-or a combination most commonly used although of these process some mills consist of four,five or six rollers in multiple sets.

TWO CLARİFİCATİON METHODS ARE COMMONLY USED: „

1. Pressure Filtration „ 2. Chemical Treatment -Phosphatation both processes required the -Carbonation addition of lime. Phosphoric acid, lime ( as lime sucrate to increase solubility) and polyacrylamide flocculent to produce a calcium phospate floc. The lime is added neutralize the organic acid, and temperature of the juice raised to about 95C

„Sugar cane juice obtained in the efficiency is by the technology used. .100kg equipment used by the manufacturer to the top three roller rattan cane juice never not draw more than 50 kg.

„Sugar produced in more than one hundred countries around the world.And appaximately 74 percent of sugar produced from sugar cane produced. „The main application areas of -sweets, -sugar and flour product, -ice cream, -candy, -jam, -marmalede, -alcoholic and non alcoholic beverages.

„Also due to the content of cellulose in the production of paper and paperboard used. „As more ethanol is used as fuel in cars.Brazil , ethanol production from sugar cane plants burning the remaining 34 percent of the positive energy from waste are sugar f ree. „In many countries including Brazil ,especially bioethanol produced from sugar cane as fuel in cars. „ Rum produced from sugar cane in Cuba.

„Sugar refinery bleaching technology,due to the nature of coal dust used in the early years.However nowadays this type of modern techonolgy the used of bleaching agents is not necessary and these system have been abondoned.

„Sugar cane is grown in Çukurova in Turkey. But is limited to the production of sugar used in industry. People used to made sugar cane juice and mollasses absorb. In addition given the leaves feed the animals. Pamace is used as the fuel and fertilizer stams.

REFERENCES

Handbook of Cane Sugar Engineering – E. Hugot (3rd Edition)1986 Sugar And Sweetener Yearbook, U. S. Department Of Agriculture, Economic Research Service, Washington, DC, June 1995.

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