While designing the system more thrust is given to the simplicity of the operation with optimum level of chemical consumption. The Syrup / melt normally has a brix of 60-62 oC, and the impurities have to be separated from the mother liquor in the form of scum that rises to the top of the surface which eventually is separated leaving the clarified liquor to be forwarded to the next unit process. Calcium Tri-Phosphate is universally known as the best colour adsorbent and hence, the first step in the system is production of Calcitum Tri- Phosphate by treating the syrup / melt with Lime Saccharate and Phosphoric acid in a specially designed reaction vessel to accomplish the reaction with provision of optimum reaction time for completion of the reaction kinetics. The syrup / melt is heated to 80 to 85 oC. before reaction vessel to achieve the desired reaction kinetics. The next step is aeration of the syrup / melt by inducing micronized air which by virtue of its fine bubble size adheres to Calcium Tri - Phosphate precipitate and other insoluble impurities. In the specially designed short retention time floatation clarifier the air bubbles are allowed to have the shortest path to the top surface and the clarified syrup / melt is withdrawn at the most silent zone. The air bubbles after reaching to the open top surface burst into atmosphere and the scum which is accumulated on the top of the surface is continuously pushed by raker arms into the scum channel. A telescopic valve is provided in the outlet line of clarified liquor to precisely monitor level of syrup / melt in the clarifier so that only the scum comprising of impurities is removed. In order to activate and boost the floatation phenomenon a floatation aid polymer which enhances kinetics of floatation is added prior to clarifier. Although major part of colouring matter gets adsorbed in the Calcium Tri- Phosphate the part which remains in the soluble form is precipitated by homogeneously mixing of the liquor with the de-colorising agent / colour precipitant.
Optimized automatic chemical dosage allows minimum recurring cost on account of chemical inputs.
No proprietary branded / chemical formulation; instead, off- the -shelf chemicals as available in open market are advised allowing reduced chemicals costs.Further there is no dependability on any particular source.
Unique design features allows duel capacity utilization. Best turndown ratio of 0 to 50%
Fully automatic dosing of all the four chemicals viz. Lime Saccharate, Phosphoric acid, colour precipitating agent and floatation aid polymer in proportion to Syrup / Melt inflow at pre-set, pre-tested dosage.
Well stabilised Syrup / Melt inflow controlled by using VFD atraw syrup /melt pump motor.
Auto pH control system
Clear melt generated from Melt clarification system contains fines and colloidal suspended solids that create visual turbidity. To improve final sugar quality it is necessary to remove these colloidal or suspended solids.
The Multi (Deep) bed filter works as a filtering unit after clarification to trap the fine colloidal suspended particles escaped from melt clarifier.
The basic concept of using multi bed filter to filter raw sugar melt is from the conventional sand filter having single layer sand filter. However, considering the nature of fine colloidal suspended solids contained in raw sugar melt the multi bed filter is used with 6 layers of graded filtering media. All the operations at this unit are provided with total automation.