How the Filter Press is Used in Winemaking
Filter presses are used for separating solids from liquids across many industries and applications. In the wine industry, the filter press is often referred to as a "lees filter."
Lees is the sediment at the bottom of fermentation vessels and includes solids such as grape skins, pulp, stems, seeds and residual yeast. Lees also contain a high percentage of recoverable product, with solids concentrations typically in the range of 20-30%, which lends itself well to dewatering via filter press.
A filter press is also well-suited for this type of application as the lees filtration process generally results in a filter cake with low residual moisture (a relatively dry cake). The lees slurry is usually combined with a filter aid such as DE (Diatomaceous Earth) and fed into the filter press using an AOD pump.