Water reclamation for hydroponic system
4 June, 2050
Waste water source
The wastewater treatment plant Hattorf (Wolfsburg) treats 8,000 population equivalents of urban wastewater. The wastewater treatment plant only receives urban wastewater without industrial discharger. All of the cities sewerage utilizes a separate system. The COD of the wastewater is about 890 mg O2/l.
After reclamation, the distribution system can either be set up as through-flow system or as a circulation system with internal storage. Seven lettuce cultivation pipes with a length of 13 m each are connected to the distribution system.
The reclaimed water is used to irrigate a hydroponic grown lettuce crop in a greenhouse. In a hydroponic system lettuce plants are grown in an artificial or peat pot to which water and nutrients are provided by a nutrient solutions that is in contact with the plant roots.
Waste water treatment description
Nutrient removal : none
Pesticide removal : Ozone and activated carbon
Disinfection : Ozone and activated carbon
Suspended solids removal : An integrated process consisting of an anaerobic/anoxic expanded granular sludge bed (EGSB) reactor and an aerobic sequencing batch reactor (SBR).
The hourly effluent of the wastewater treatment plant Hattorf is about 45 m³/h. The reclamation facility for the hydroponic system can treat 720 l/d.
Extent of the agricultural beneficiaries
The hydroponic growing area is about 100 m² and consists of seven lettuce cultivation lines with a length of about 13 m.
Funding is done by the ministery of research. The cost of the reclaimed water isn't known.
Type of agreement
Bliedung, A., Dockhorn, T., Germer, J., Fiebig, B., Peters G., Rossmanith, P., Wieland, A. (2019): The HypoWave-System – Nutrient and heavy metal flows within an integrated system of adapted wastewater treatment and subsequent water reuse in a hydroponic system. Book of Abstracts – IWA Water Reuse 2019, Berlin, 552-557
Schramm, E., Dockhorn, T., Ebert, B., & Winker, M. (2018). Wasserwiederverwendung im Gemeinschaftsrecht/Water reuse in European Communities law. Institut Für Sozial-Ökologische Forschung, 43. Retrieved from http://www.isoe-publikationen.de/fileadmin/redaktion/ISOE-Reihen/dp/dp-43-isoe-2018.pdf
The pilot plant and several case studies have shown the potential of the HypoWave process as an alternative cultivation method. With the reclaimed water of small communities of 500 and 1,650 person equivalent, an economic production can be achieved on 3,600 and 6,000 m².