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The Syrup clarification system generally used in plantation white sugar making process and Melt clarification system used in refinery sugar and sulphur free sugar process. The fundamental concepts and way of process are the same in both SCS and MCS systems. However good juice clarification may be, there is a large increase in turbidity of about 80% across the evaporators. The syrup clarification system very much helpful to reduce the turbidity as well as colour of syrup.

The Phosphoflotation process works on the principle of forming low density aggregates of particles and bubbles, and lower the density, more quickly they float. The process of phosphotation consists of screening the liquor to separate the coarse suspended solids and then dosing the liquor with phosphoric acid and lime sucrate. The resultant precipitate, after occlusion and absorption of the fine suspended solids, colloids and coloring matter, is floated with the aid of air bubbles enmeshed in the floccules.

The special design of Flotation clarifier with appropriate chemicals results in the entrapment of the suspended matter and colour causing impurities.

The system of syrup and melt clarifications mainly consists of following steps.

a) The syrup or melt collected in buffer tank and heated up to 80 to 85 O C by using heater.

b) The heated syrup is then passed through a specially designed reaction vessel. Before entering the reaction vessel added chemicals colour precipitent, Phosphoric acid and Lime sucrate with appropriate dosing.  After reaction vessel the syrup sent to aeration system for resulting in optimum flotation.

c) Flocculant is then added to aerated syrup and is sent to the froth clarifier, specially designed for separation of clarified syrup and the impurities in the form of scum, clarified syrup is further sent crystallization process.

 The interaction of calcium and phosphate ions leading to precipitation of Tricalcium phosphate is the principal chemical reaction of the flocculation. Other reaction involved are the interaction of calcium with acids present in the liquor, neutralization of colloidal charges induced by calcium cations and also surface absorption of suspended solids, micro floc and soluble color.

a) Phosphate precipitation is a time reaction and slow to approach equilibrium.

b) The rate of reaction and the quality of the precipitate are significantly affected by the nature and concentration of the impurities, and, of course, by the viscosity of the liquor.

c) The effectiveness of tricalcium phosphate as being efficient in removing significant proportions of turbidity and colour when added to the melt prior to filtration. They have also shown that the colors so removed are those associated with iron polyphenols, a grade of colour which is very difficult to eliminate by any other treatment.