INCREASED PRODUCTIVITY AND LOWER TOTAL COST OF OWNERSHIP BY USING SCALE RETARDANT FILTER MEDIA FOR BAYER LIQUOR CLARIFICATION

Scale formation is a major issue for most filter equipment and filter media used in the Bayer process. Scaling occurs particularly in the filtration area during the liquor clarification process; it limits the service life of filter cloths, which increases the cost of ownership. Knowing that scaling is a crystallisation on the yarn surface of the filter media, attempts have been made to delay this premature crystallisation. The solution comes from an improved polymer formulation used during yarn spinning. Woven filter media made of the improved yarn were compared to the standard yarn formulation in real conditions of operation. The results showed that the liquor flow achieved with improved yarn formulation was higher and decreasing more slowly than for the standard yarn formulation. The improvement of liquor flow along with the service life increase provides a reduction of filtration cost.