Design and performance evaluation of a highly loaded aerated treatment wetland managing effluents from a food processing industry in Denmark

Treating highly loaded industrial effluents are challenging when treatment wetlands (TWs) are the choice selected for treatment. If TWs are selected as the solution, passive systems demand relatively large areas and may generate operational limitations and are not flexible in case of new treatment demands since no process adjustments can be made once the system is built. New types of intensified TW, such as aerated systems, have opened new possibilities in the field of the Wetland Technology and have shown capacity to treat several types of wastewater (WW). Aerated wetlands have been built across the USA and several European countries, but not a single system has been built in Denmark as to date. Thanks to an EU funded project and the cooperation of several partners under a consortium with the acronym HIGHWET, a new system is being built at the premises of a food processing factory in the vicinity of Faarup Denmark. The system will treat the WW generated at the plant and consists of a pretreatment system in the form of an anaerobic reactor, followed by two 1 m deep vertical flow beds, one of them aerated while the other bed is not aerated. Following these beds, the plant has two horizontal sub-surface flow beds fitted with aeration. For improving the P removal, media with high P binding capacity is are being used as filling material. In additiuon and for research purposes, the influent pump well plant is fitted with a dosing system in order to obtain pollutant loads at will so performance limits and kinetic constants can be established from the performance of the plant.