PROCESS DESCRIPTION

Processing of raw sugar to refined sugar involves the following steps:

1. Affination & Melting

• Raw sugar stored in the godowns is brought to the process house by conveyors. After breaking the lumps formed during the storage, the raw sugar is conveyed to the raw sugar bin by a belt conveyor and sugar elevator and is automatically weighed and then sent to a Mingler for preparing a magma with hot water and affined syrup. The magmised raw sugar is centrifuged through a set of Automatic Centrifugal Machines. Affined sugar from these machines is melted in a specially designed melter. The quality of affined sugar is controlled through automatic control of various parameters to remove maximum colour. Brix is maintained between 62-650 and the temperature of the melt is maintained at 600C. The colour value of the affined sugar melt is reduced and should be between 1200 – 1500 I.U.

2. Clarification

• The melt is next passed through a set of vibro-screens to remove bagacillo and other extraneous materials.
• The melt after screening is sent to a Buffer Tank for dosing with a specially anionic colour precipitant to remove the coloring and other colloidal impurities. The melt from buffer tank is then sent to the Reaction Tank for addition of lime sucrates and phosphoric acid to maintain a final pH of 6.9 to 7.0 pH for precipitation of impurities. The reacted melt is again heated to 850C in the tubular heater and sent to a constant head tank for feeding to the froth clarifier through a specially designed aeration unit & a flocculator. The micronised air assists in floatation and after dosing of flocculant in the flocculator, the impurities float as scum in a specially designed clarifier and is removed by rotating scrappers. The clear melt is drawn from the clarifier through weir box and sent for filtration.
• The scum contains entrapped sugar and is desweetened in the desugarization system.
• The maximum colour and ash are removed in the clarifier and the colour value after the clarifier is about 600-700 I.U.

3. Filtration

• The clarified liquor is filtered in a two stage system to remove all micro suspended impurities. In the 1st stage the filtration is done through deep bed filter and in the 2nd stage through Leaf Filters. Some colour reduction is also observed during filtration.

4. Decolourisation

• The filtered liquor after the two-stage filtration is passed through a set of ion-exchange resin columns (acyrlic and styrene based) for maximum removal of ash and colour.
• A colour value of 150-200 I.U. is achieved at the exit of the resin column. The Fine Liquor is used for refined massecuites boiling.
• The resin bed is periodically regenerated by brine & HCI solution.

5. Pan Boiling & Curing (Boiling Scheme for refined & recovery boiling)

• The boiling station is designed for six boilings – R1, R2, R3 (refined boiling) and Ry1, Ry2, and Ry3 (recovery boiling).
• The fine liquor received is used for R1. The run off from R1 massecuite is used for producing R2 massecuite. Similarly, the run off from R2 massecuite is used for producing R3 massecuite. The run off molasses from R3 massecuite is sent to recovery house for recovery boiling.
• The sugar from R1, R2 & R3 massecuites is cured in auto centrifugal machines to separate the mother liquor and the refined sugar is then dried, cooled and sent to conditioning bins. From the bins it is weighed, stitched and sent for sugar storage.
• The run off molasses from R3 massecuite is mixed with affined syrup from affination of raw sugar and is used for Ry1 boiling. The molasses of Ry1 is used for making Ry2 massecuite and similarly, Ry2 molasses received is used to make Ry3 massecuite. Ry3 massecuite is double cured. The sugar received from Ry1, Ry2 and Ry3 is melted for further reprocessing whereas the molasses of Ry3 is discharged/sold.
  

LIST OF EQUIPMENT

Production Capacity : 750 TPD

Top   |   Back