Candle filter is also called filter cake layer filter which is a kind of automatic fine filtration equipment with high efficiency and no environmental pollution.
Candle filters provide for thin-cake pressure filtration, cake washing, drying, slurry, and automatic discharge. Units are available from 1 m2 up to 60 m2 of filter area per vessel. Working pressure: 0.3-0.35MPa. The clean removal efficiency to <1 micron (μm). As the cake builds up, removal efficiencies improve to <0.5 μm.

According different flow capacity, there are one or more cartridges inside the filter vessel, and a special kind filter cloth is used according to the source of fluid characteristics. When the liquid goes through the filter cloth, solid will be gradually gathered on the surface of the filter cloth. The so-called "filter cake layer" has been formed when this solid material reaches a certain thickness. Because the gap among the particles in the filter cake layer is very small, the particulate of impurities in the liquid is retained. The filtrate is clear and the filtration effect required by the production is achieved.