How Filter Presses Work？

Filter presses are used as a fixed volume, batch operation process. First, a pump feeds the wastewater slurry into the filter press unit. The slurry enters filter cloth chambers and the filtrate exits through the cloth, while solids are trapped and compacted into cakes. Once a batch is complete, the filter plates open and the solid filter cakes are removed.

There are two main components that make up a filter press:

• Filter Plates – The filter chambers are constructed of rectangular plates lined with filter cloths. The plates are sealed on all sides and arranged side-by-side in a frame.

• Filtrate Head – The head applies pressure to the filter chambers to enhance the filtration process. It collects and discharges the filtrate.

Types of Filter Press

There are several different filter press designs and models available for handling various waste slurries.

• Plate and Frame – This is the most common type. It uses separate framed plates lined with cloth, separated by gaskets.

• Chamber – Chamber filter presses contain pre-assembled plates in a filter block design. This allows faster maintenance.

• Membrane – Membrane filter presses utilize pre-coated filter cloths. Flow passes through the cloth, not between chambers.

• Belt – Belt filter presses are continuous processes rather than batch. Two belts compress the sludge and move it between heavy rollers.

Applications In Wastewater Treatment

Filter presses are utilized for several important functions in the wastewater treatment process flow:

• Sludge Dewatering – Thickening and dewatering sludge is a crucial treatment step. Filter presses remove excess water from the sludge before disposal.

• Slurry Separation – Filters separate undesirable solids like fats, oils, and grease from wastewater streams entering the plant.

• Algae Removal – Filters remove algae from clarified water before disinfection and discharge.

• Chemical Treatment – Adding coagulants/flocculants causes particles to clump together. Filters remove these larger particles.

• Leachate Processing – Landfill leachate contains contaminants requiring filter pressing for solid-liquid separation before further treatment.