Pressurized filtration is the most common pretreatment method used in of water treatment. The pressurized filtration requires a filter feed pump(s) and a filter vessel(s). The purpose of pressurized filtration is the removal of suspended solids and other contents of water. The operating pressure ranges from 2.5 - 6.0 bar, the size and constituents of the filter depend on its purpose. Mainly two support layers one a top another followed by another smaller grain size supportive layer as well as an active layer. The active layer may be sand for filtration of suspended solids, birm for removal of iron, carbon for removal of chlorine & odor, anthracite for fine filtration, etc…

The design of the filter vessel requires a case study on the application and varies from one to another.

The Silt Density index should be maintained below 3. Proper periodic backwashing insures longer and better operating regimes.