The filter press is a highly efficient and effective device for liquid / solid separation under pressure. The ALSI filter press design produces clearer filtrate and a drier filter cake than other filtration alternatives. Our customers have acheived up to 80 percent solids in certain applications.

Our filter press is unique in its construction and operation. The design has been tailored for zinc phosphate filtration as well as other difficult filtration processes. A header assembly is fabricated with 316L SS with flanged connection points to minimize any possibility for leakage. Utilization of a flow meter and pressure switch in conjunction with a VFD control system allows for automatic operation that is very effective when applied to many applications.

Particles under pressure are uniformly deposited on the surface of the filter cloth. This initial build-up becomes the filter media. The clarified filtrate passes through the cloth and is channeled to the discharge ports. The discharge stops when the chambers fill with solids and the liquid supply pump is signaled to turn-off based on pressure differential. To remove any excess liquid remaining in the press, air blowdown is utilized. Blowdown is accomplished by introducing pressurized air into the center feed line directly where the line enters the head plate.

Dewatering of the solids occurs as the air forces remaining liquid toward the discharge ports at the corner of each filter plate. The plates are then separated by turning the selector switch to the “open” position, and sliding the lightweight plates apart to reveal the dried filter cakes. The removed solids are allowed to fall from the chamber recesses, through a chute and into a hopper below. The filter plates are closed by turning the selector switch to “close”, which activates a pneumatically actuated hydraulic pump to cycle on and press the plates closed. The filtration process then re-starts once the liquid supply pump is signaled to resume operation.


  • Operation is automatic and requires little monitoring.
  • Durable filter cloths are designed for long life and easy release of filtrate solids.
  • Filter plates are lightweight and easy to handle.

Click here for ALSI Literature on Filter Presses.

Please contact us here.