Filtration of Sugar Syrup
When referring to sugar syrup we mean cane sugar at 60° - 68° brix and at a filtration temperature of 70° - 85°C. The quality of sugar syrup differs widely depending on its origin and refining process. In the "bottlers' industry" the purity of the sugar solution is measured in ICUMSA or RBU units. A high ICUMSA or RBU reading (150 - 450) indicates a poor quality sugar and means it is difficult to process. The international accepted standard (Coca-Cola) for sugar syrup 65° brix is less than 50 ICUMSA.
To reduce the ICUMSA / RBU readings the syrup is treated heavily with activated carbon (AC). The AC dosages range from 0.2 - 0.5 - 0.8 % (w/w). Because of the high dosage of AC, filters with a large sludge volume should be used and can withstand high pressure / pressure differential. In cases where a continuous filtration process is required, it is advisable to use two filters so that while the one filter is ON-LINE the second filter can be on CIP or STAND-BY.
FILTER-O-MAT® / SYNOX® - DE-Filtration
For the filtration of sugar syrup, good results are obtained when using a horizontal pressure leaf filter (FILTER-O-MAT 110) or a candle filter (SYNOX) whichever filter system is preferred. Both these filters are designed to withstand prolonged high temperatures and working pressures. Furthermore the filters are available either as hand-operated plants or fitted with pneumatic control systems, associated software and safety features.
NOVOX® - Plate and Frame Filter
In the case of good quality sugar (low ICUMSA readings), a plate and frame filter may be used instead of a standard DE-filter. Plate and frame filters can however only be automated with difficulty and are labour intense for cleaning.
FIBRAFIX® - Depth Filter Sheets and Washable Sheets
A wide range of depth filter sheets with different pore sizes are available, however for the filtration of sugar syrup a coarse filter sheet (AF 9) is recommended. Filter sheets can be sterilized with hot water and then re-used for a period of days. Filtrox also produces a "carbon impregnated filter sheet" designed for special duties and products.
DISCSTAR® - Lenticular Filtration - Depth Filter Module Filtration
This type of filtration system can be recommended for all products with a high degree of clarity, prior to filtration. The filter can very snugly be built into any pipe system and according to the pore size of the lenticular cartridges (modules), it can be used as a police filter, polishing filter or for sterile filtration. Lenticular cartridge filters can be drained with ease, can be sterilized with hot water or steam and re-used. Filtrox also produces a "carbon impregnated module" specially designed for the filtration of special products.