Affination Process in Sugar Refinery with Material balance Calculation

Affination Process in Sugar Refinery with Material balance Calculation:-  In this article discussed about factors involved in affination process of standalone refinery with material balance calculation.

Material Balance of Affination Process in Sugar Refinery:-

What is Affination Process:-

Affination process is a first step in the sugar refinery process when high colored raw sugar taken as a input material. This process can be defined as washing and consists of removing the adhering film of molasses from the surface of the raw sugar crystal which is input raw material of sugar refinery.

In affination process involves mingling the input high colored raw sugar with affination liquor (Which is obtained in same process after centrifuged) and purging the mixture in centrifugal machine with hot water washing after the syrup has been spin off. After this process obtained two products named as affinated sugar and affination liquior.

The Affinated raw sugar directly taken to raw sugar melter and some required quantity of affinated liquor used for same process and remaining quantity sent to recovery house for massecuite boiling.

Operating Condition in Affination :-

Temperature of mingling affinated liquor

The purpose of the affination is to remove the sticky high colored molasses film. Hot mingling is best practice to reduce the viscosity and maintained around 70 to 75oC and magma temperature will be around 45 oC.

Parameters

Affination liquor brix                   72 to 74%

Affination liquor purity               75 to 85%

Affination liquor temperature   70 to 75 oC

Affination magma brix                90 to 92%

Wash water temperature           85 to 90 oC

Quantity of wash water             Depends upon required affination brix and colour of raw sugar.Examples of Solids and Purity Balance for affination of raw sugar in refined sugar process

Example – 1

Input parameters

S.NO	Description	Values	UOM
1	Raw Suagr Quantity	100	T
2	Raw sugar Brix	99.7	%
3	Raw Sugar Purity	98.8	%
4	Affinated liquor Brix	75	%
5	Affinated liquor Purity	85	%
6	Magma Brix	90	%
7	Affinated raw sugar brix	99.7	%
8	Affinated raw sugar purity	99.5	% Calculation: Quantity of affination liquor  for magma preparation – 64.67 T Add caption Hint :  (((Quantity of raw sugar X raw sugar brix) – ( Qty of raw sugar  X magma brix))/ (Brix of magma – Brix of affination liquor) Magma Quantity = 100 + 64.67 = 164.67 T Purity of Magma = 93.38% Hint:    Affi. Raw sugar 99.5 8.38 Magma 93.38 Affi. Liquor 85 6.12 14.50    S.NO  Description  Quantity  Solids UOM  1  Affination Magma  164.7  148.2 T  2  Affinated Raw sugar  85.91  85.7 T  3  Affinated liquor  83.39  62.5 T  4  Wash water  4.64  0 T  5  Affinated liquor for magma preparation  64.7  48.5 T  6  Affinated liquor send to recovery house  18.73  14.04 T Example – 2 Input parameters S.NO  Description  Values UOM  1  Raw Sugar Quantity  100 T  2  Raw sugar Brix  99.7 %  3  Raw Sugar Purity  98.8 %  4  Affinated liquor Brix  75 %  5  Affinated liquor Purity  80 %  6  Magma Brix  92 %  7  Affinated raw sugar brix  99.7 %  8  Affinated raw sugar purity  99.5 % Calculation: Quantity of affination liquor  for magma preparation – 45.3 T Hint :  (((Quantity of raw sugar X raw sugar brix) – ( Qty of raw sugar  X magma brix))/ (Brix of magma – Brix of affination liquor) Magma Quantity = 100 + 45.3 = 145.3 T Purity of Magma = 92.24% Hint:  Affi. Raw sugar 99.5 12.94 Magma 92.94 Affi. Liquor 80 6.56 19.50    S.NO  Description  Quantity  Solids UOM  1  Affination Magma  145.3  133.671 T  2  Affinated Raw sugar  88.96  88.7 T  3  Affinated liquor  59.96  45.0 T  4  Wash water  3.63 T  5  Affinated liquor for magma preparation  45.3  33.9706 T  6  Affinated liquor send to recovery house  14.67  11.00 T Conclusion : From the above examples, The quantity of solids are sent to recovery house will be reduced while maintaining the proper brix of magma and control the purity of affination liquor as much as possible. If the quantity of solids of send to recovery house from affination process will be increased then massecuite % and final molasses percent is also increased. Colour reduction in this process will be obtained around 50 to 60% on input raw sugar color. Some times more percent reduction required for input raw sugar colour having higher side. For this we go for more washing in centrifugal section and at the same time losses also will be increased.