The refining of sugar from both sugar cane and sugar beets typically involves melting the sugar down into syrup. In this liquid state the sugar is filtered through liquid filters to remove impurities and as a step in the decolorization process. Sludge generated by other clarification processes is dewatered by liquid filters to minimize product loss. Menardi is a leading supplier of fabric filters for the pressure leaf filters and rotary vacuum drum filters typically used in these applications.
The most important design considerations for sugar refining liquid filters are fabrics that will resist blinding and plugging by the organic contaminants that must be removed, yet are heavy enough to remove the very fine particulate and resist abrasion.
Common process problems:
- Excessive labor costs associated with frequent filter changes
Menardi product solutions:
- Newer generation monofilament/multifilament filtration fabrics
- Snap cord closures
- Velcro® closures
- Zipper closures
Clarification of cane sugar syrup traditionally utilized spun and filament/spun polyester fabrics that did an excellent job of removing the fine particles present in the unfiltered syrup. However, the polyester was subject to failures due to abrasion and plugging in a relatively short period of time. This combination resulted in short filter cloth life and consequently high labor and downtime costs associated with changing filter cloths.
Menardi was one of the first fabric filter manufacturers to introduce monofilament/multifilament polypropylene fabrics that were capable of withstanding the elevated temperatures in this application. The monofilament/multifilament construction minimized the plugging problem and the polypropylene resists abrasion while keeping costs at an acceptable level.