| Depending on the type of water, suspended solids concentration, oil and grease, COD/ BOD, iron contents, sand filters are sized differently, but the basic design data to clarify natural waters are the following: | | Filtration velocity | 6-15 m3/h.m2 | | Diameter | 50 cm to 1m | 1 to 3m | | Filtration area | 0,2 to 0,8 m2 | 0,8 to 7 m2 | | Flowrates | 10L/h to 10 m3/h | 10 to 100 m3/h | | Pressure ratings | 4 to10 bar | | Vessel Materials | Epoxy-coated steel | | Polyester composite | | Stainless steel (on request) | | Bed depth | 1 meter min. | | Filtration media | Anthracite 1.4-1.5 mm | | Sand 0.4-0.8 mm | | Sand 1.0-2.0 mm | | Gravel 2.0-3.15 mm | | Gravel 3.15-5.6 mm | | Top manhole | 2 1/2 to 6" | DN 400 | | Accessories | 5-ball or butterfly valves | 5-butterfly valves | | Options | Manometers, degaser, flowmeter | | Control | Automatic or manual backwash, on timer and/or differential pressure | More on sand filtration |  | |