As a general rule of thumb, vacuum and gravity filters are typically used for faster filtering materials, whereas pressure filters are used for slower filtering materials.  Below is a chart that may aid in filter selection: Slurry Characteristics Fast Filtering Medium Filtering Slow Filtering Dilute Very Dilute Cake Formation Rate in/sec in/min 0.05 to 0.25 in/min <0.05 in/min No cake Normal concentration >20% 10-20% 1-10% <5% <0.1% Settling Rate rapid, difficult to suspend fast slow slow ----------- Leaf test rate (lb/hr/sq ft) >500 50 to 500 5 to 50 <5 ----------- Filtrate rate (gal/min/sq ft) >5 0.2 to 5 0.01 to 0.02 0.01 to 2 0.01 to 2 Filter Application Continuous vacuum filters: Multi-compartment drum X X X Single compartment drum X Hopper dewaterer X Top feed rotary drum vacuum filter X Tilting pan X X Horizontal vacuum belt filter X X Disk X X Precoat rotary drum vacuum filter X X Continuous pressure precoat X X Batch vacuum leaf X X X X Batch nutsche X X X X X Batch pressure filters: Plate & frame filter press X X X X Vertical pressure leaf filter X X X X Tubular/candle filter X X X X Horizontal pressure plate filter X X X X X Cartridge X X