The thin fraction of pig manure, after biological purification in an activated sludge plant, is treated in various stages of helophyte filters. The manure is passed through several flow fields, but it is the first stage of manure processing horizontal filter. This anaerobic biofilter, filled with blast furnace slag, mainly removes nitrogen.
In Wortel, near Hoogstraten, Rietland, in collaboration with Innova Manure, laid out a reed bed for the processing of the liquid fraction of pig manure. The system is designed to treat 60 m³ effluent from biological treatment to discharged water per day. The system consists of 22 basins and has a total area of 1.2 ha. The various cymbals each have their own function. There are, for example, an aerated stage and percolation reed fields for the removal of COD and the conversion of ammonium into nitrate. Furthermore, a large part of the reed field consists of flow fields to remove nitrate.
