A new corrosion resistant fume-tight Pannevis RT filter from Larox make it possible to safely and efficiently process hazardous or toxic materials, or materials sensitive to outside contamination when the process is too corrosive for conventional materials. The new filter is constructed with the filter housing formed entirely of FRP and with all internal process contact surfaces of non-metallic, corrosion-resistant materials. Where the strength of metal is required in items that are subject to only indirect contact with the process then Hastelloy or other exotic materials are used, making the system 100% corrosion resistant inside the housing.

The new filters are fully enclosed systems based on the proven RT reciprocating tray concept, making it possible to carry out multi-step process operations in a single unit, including filtration, co-current or counter-current washing and cake drying. They operate with a normal air atmosphere while processing either hazardous or toxic materials, or materials that require containment. For hazardous or toxic products the filter is normally operated with a slight under-pressure inside the housing ensuring only in-leakage while contaminant-free operation uses a slight over-pressure of clean, filtered air to ensure a small out-leakage, eliminating external source contamination to maintain product purity.

Where contaminant free operation is required for hazardous or toxic materials, a similar unit, upgraded to Gas Tight filter specifications can be operated with closed loop re-circulation of the filter atmosphere.

The filter housings feature curved roofs and floors for ease of cleaning and drainage and can also be equipped with a built-in clean-in-place system. Also, as with all Pannevis enclosed filters, the majority of potential maintenance parts are located outside the housing to minimize the need for vessel access. Access, when required, is provided by large manways on both sides and both ends of the filter, or by removal of the end plates.

Larox also produces a full line of Pannevis Fume Tight filters for sanitary applications such as food or pharmaceutical processing.