VUNA - Nutrient Harvesting


By recovering nutrients from urine in small decentralized reactors we developed a dry sanitation system which is affordable produces a valuable fertilizer promotes entrepreneurship and reduces pollution of water resources.


Our body excretes the majority of nutrients in the urine (and not in the faeces). By collecting urine separately we can recover valuable nutrients e.g. nitrogen phosphorus potassium or sulphur. At the same time we prevent pollution of surface waters with high nutrient loads.; In Zurich at Eawag all toilets at the main building Forum Chriesbach divert the urine into a separate pipe system. After storage a pilot-scale treatment unit at the basement transforms the urine into a concentrated nutrient solution. Currently about 75 L of urine are processed every day producing on average 3 L liquid fertiliser and 72 L distilled water which is recycled into the building's toilet flush water system. In Durban the eThekwini municipality collects urine from household urine diverting dry toilets (UDDTs) and processes it at the Newlands-Mashu DEWATS Demonstration Plant test site. The site hosts several trials on nutrient recovery fertiliser application or decentralised wastewater treatment. (contact: Bastian Etter -...

Date of release