Vacuum and Pressure Filtration work most efficiently if the feed solids concentration is high. Therefore low concentration slurries can first be thickened in a thickener-clarifier.

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Easy filterable applications with large capacities are well served by continuous filters, like Rubber Belt Filters and Drum filters.  Cake heights are usually high, like 5 cm but also higher is seen.

In case of longer filtration times, the cake height is reduced to 1 – 2 cm.  These filters operate without rubber sealing belts and on the principle of reciprocating trays.  These are thin cake filters which can run at much lower belt speed.

All of these filters are fed continuously and also discharged continuously without stopping the feed.

Cake wash is excellent on horizontal belt filters but also possible on drum filters, though less efficient.  Both Belt and Drum filters allow mechanical squeeze dewatering by mechanical pressure sections towards discharge end.  Final drying is sometimes possible on belt filters by means of steam injection, hot air or IR.