By Andritz |
Vacuum drum filters are state-of-the-art in highly corrosive applications like producing titaniumdioxyd (TiO2) in sulfuric acid (H2SO4) processes or in processes where slurries with a high content of hydrochlorid acid (HCl) are used. Conventionally, these filters are made out of carbon steel covered with rubber lining to protect the structural design of the machine against corrosive attacks. Disadvantage of this rubber lining is a partly embrittlement with tendency for cracks in relatively short time and therefore high maintenance costs with unscheduled production interruption.
In the past, filters completely made out of glassfibre reinforced plastic (GRP) were not long-term useable because of structural weaknesses of this material by chemical attacks along the glass-fibers due to capillary effects. Also, filters completely made out of thermoplastics failed because of poor material properties. The new CORES vacuum drum filters are designed in a different way. Structural design is, dependent on size, made out of steel or completely out of GRP. In addition, all parts in contact with the product are covered with a layer out of corrosion resistant, not reinforced plastic, which is commonly used in such industries, like PP (polypropylene) or PVC. Furthermore, some internal wetted parts can be completely designed out of resistant plastic and will be welded together with external surfaces out of plastic to have a closed surface for these corrosive applications.
The process functions of a vacuum drum filter still remain the same, but corrosion resistance of these new CORES filters are significantly increased compared with traditional carbon-steel rubber lined execution or conventional GRP filters without thermoplastic-layer coverage. Read more about this topic by downloading the whitepaper.