Syrup Clarification
Syrup clarification is useful for producing higher quality plantation white or direct consumption sugar with lower IU colour and lower residual sulphur dioxide levels.
National standards for residual sulphur dioxide and colour have been lowered to reflect the growing demand for improved quality and concerns for health risks.
Limitations Of Syrup Clarification System:
Increase Unknown losses : It may occur inversion losses due increasing the temperature of syrup and retention time across the system so it will effect the recovery. To overcome of this by maintain optimum required temperature with pH and retention time.
Foaming Problem : Excessive foaming observed in buffer tank and clarifier while decreasing the brix of material. So always try to maintain the brix around 60 and to overcome this problem, temporarily by using of anti foaming of fatty acids is advisable.
De Sweetening of Scum : The formation of the scum in melt clarification system is around 40 to 60 Ltrs per ton of melt flow and in syrup clarification system it will be around 2 to 3% on syrup flow rate The scum having the purity approximately 5 units less than the material purity (syrup or melt). So De-sweetening of scum is essential in both systems. The Syrup clarification system scum is better to divert juice sulphitor. The melt clarification system scum is better to divert three stage scum De-sweetening system. In back-end refinery plants the MCS scum also diverted to juice defector.
Brix of material : The brix of material required around 60 deg. to get better results. Now a day according to energy conservation point of view maintain the syrup brix more then 65 deg. In syrup clarification system (SCS) to overcome of this problem is better to divert 4th effect syrup to syrup clarification system. In melt clarification system (MCS) to overcome this problem by installing the melt concentrates.
Advantages:
- Reduction of turbidity up to 90%.
- Removal of maximum Bagacillo and suspended solid.
- Reduction of ICU MSA colour up to 25%.
- Reduction of viscosity of syrup and further process material.
- Faster crystallization, higher exhaustion and less final molasses purity.
- High quality sugar with less sulphur content.
- Lower IU colour sugar.
- Filtrate coming from vacuum filter is very low in purity, rich in gums and non-sugars.
- This filtrate is directed towards the mixed juice, and it will have adverse effect in processing.