No Slide Title

CLARIFICATION AND DESALTING OF CANE JUICE FOR HIGH YIELD

DR. B. CHAKRAVORTY

GENESIS MEMBRANE SEPRATECH PVT. LTD.Mumbai, India.Tel.: 91-22-5775456; Fax: 91-22-5790608; E-mail:genesis@bom5.vsnl.net.inby

TOTAL SUGAR PRODUCTION (INDIA )

Prodcution as of April 2012 is 3

PRODUCTION OF CANE ( INDIA )

5

NO. OF PLANTS WITH CAPACITY

There are 671 sugar mills in India.

In 1950, there were 139 sugar factories in the country with an annual installed capacity of 1.67 million tonnes.

Today, India has about 671 sugar factories with an annual sugar production of 24.1 million tonnes.

India has 20% of the total sugar mills in the world and accounts for about 15% of the global production.

IntroductionIndia is the second largest producer of sugar from cane after Brazil.

Production capacity is 24 million tons / year.

The total sale value in 1999 is 5 billion US$.

Total capital employed around 4 billion US$.

Better quality cane with higher sucrose content has been the biggest contributor to this industry.

However manufacturing techniques have not changed much.

The average recovery varies from as low as 7% to as high as 13% whereas sucrose content in the cane can be 18%.

Efforts are directed towards better manufacturing technique to achieve higher yield.

CANE CRUSHINGBLOCK DIAGRAM FOR CANE SUGAR PRODUCTIONLIMINGHEATINGTHIN JUICEEVAPORATIONCRYSTALLIZATIONMOLASSESRAW SUGARCaOSTEAMTHICK JUICERAW JUICE

SUGAR MANUFACTURE

(CANE MILLLING)Sugar Cane

Cane Carrier

Cane leveller or kicker to feed the cane cutting knives uniformly

Cane cutter-Ist cutting the cane to pieces

Mincer - IInd stage of cutting to finer pieces

Milling TandemComprising of Six mills

SCHEMATIC ARRANGEMENT FOR JUICE CLARIFICATION

Raw Juice pH 5.0

Heated to 650C on Juice Heaters

Simultaneous Liming and Sulphitation and the final pH is kept around 7.0/7.2

Heated to 102 0 C on Juice Heaters.

CLARIFIER

Subsequently juice is allowed to settle for 2.5 hours. The CLEAR supernatant juice is separated for further processing. The non-sugars precipitated as calcium sulfite complex compounds are further treated on Rotatory Vacuum Filters (RVF) for futher extraction of residual juice.

SUGAR MANUFACTURE (CONTD.)Prepared cane is subjected to twelve compressions which helps to squeezethe juice with application of high pressure. At final stage water is added andthen squeezed so that no sugar is left when the material leaves the Mills. The product after milling or extraction of juice is known as bagasse.

Juice delivered to the Boiling House Bagasse Bye Product for Clarification and Sugar Boiling (Fibre + Water + Little salts) Used as fuel in Boilers 5% sold to paper industries

Muddy Juice Clear Juice (15o Brix)

Rotatory Vacuum Filter Vapour Cell (For part Evaporation)

Filter cake or PressFilter Juice Quadruple Effect Evap.Mud (Bye product.(Back to the Juice (Evaporation of waterSold to farmers to tank to be mixed up to 75%)be used as manurewith raw juice and for the cane fields)re-processed) Concentrated material (called SYRUPof 60 Brix) Sulfitation Sulfited syrup pH 5.0CLARIFIER

BOILING PROCESS IN VACUUM PANS

I Stage:Syrup + B-seed + Melt from C-double cured Sugar

A-massecuite

Batch Centrifugal

A-Light & A-Heavy MolassesFinished Product Sugar

Hopper-Drying & Cooling

Grader

Powder Graded Sugar

Weighing Stitching

Sugar Godown

II Stage:

A - Light & A - Heavy Molasses

B-Massecuite

Continuous Centrifugal Machines

B - Seed. B - Heavy Molasses.Magmised and used as seed for A-massecuite.

III Stage:B - Heavy Molasses + C - Light Molasses

C - Massecuite

Continuous Centrifugal Machines

Magmised Final Molasses to storage tanks (A bye-product sold to distilleries producing rectified spirit, Second Curing alcohol, etc. )Continuous Centrifugal Machines

C - Double Cured sugar C- Light Molasses (Rich in sugar and therefore(Melted to give clear melt. sent back to the process forThis is pumped to the pan C-Massecuite boiling)floor and boiled with syrup to produceA - massecuite)

Repeat the four-step process under Point #1.

CORELATION OF PERMEATE FLUX WITH CONCENTRATION ON SPRIAL MEMBRANE

21

CORELATION OF PERMEATE FLUX WITH CONCENTRATION ON TUBULAR MEMBRANE

CORELATION OF PERMEATE FLUX WITH TEMPERATURE ON TUBULAR MEMBRANE

CORELATION OF % LOSS OF SUCROSE WITH CONCENTRATION

CORELATION ON DEGREE OF DESALTING WITH CONCENTRATION

THANK YOU

STAGE II DESALTING &

PRECONCENTRATION OF

CALRIFIED MIXED JUICE TO 23 BRIX

To Evaporator

Clear Juice

12,000 l/h

Brix : 11.5 12.0

Purity : 82 - 84

Settling

Tank

Chemical

6,000 l/h

Brix : 1.5

Partly to Cane Washing

4,500 l/h

500 l/h Filter Residue to

RVF

STAGE - I CLARIFICATION OF MIXED JUICE

Desalted Juice

6,000 l/h

Brix : 22 -23

Purity : 89 - 91

Temp : 45-50oC

Mixed Juice

10,000 l/h

Brix : 15

Purity : 76-80

Temp : 50-55oC

5,000 l/h

Clear juice; 7,500 l/h

Hot Water 550C

2500 l/hr