Filter press (sometimes called Plate-and-Frame Filter press) which describes the style of filters developed from the 19th century onwards originally for clay. The majority of today's filters are more correctly called "chamber filter press", "Membrane filter press", or "Membrane Plate Filter".
Many processes in the food, chemical or pharmaceutical industries make products from liquid-solid suspensions or slurries. These mixtures are like a runny mud or milk shake.
The solids in them do not dissolve in the liquid, but are carried along in it. Filter presses separate the solids from the liquids so that the useful part can be processed, packaged or delivered to the next step.
Filter presses generally work in a "batch" manner. The plates are clamped together, then a pump starts feeding the slurry into the filter press to complete a filtering cycle and produce a batch of solid filtered material, called the filter cake. The stack of plates is opened, solid is removed, and the stack of plates is re-clamped and the filtering cycle is repeated.