Urine as the raw material of the future?

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Urine as the raw material of the future?

Bill & Melinda Gates Foundation supports Swiss water research for South Africa.

The separate collection of urine allows innovative solutions for improvements in sanitation and recycling of the nutrients nitrogen, phosphorus and potassium. Especially in places where a Western European-style alluvial sewer system does not offer a sustainable solution, urine separation is a great opportunity. Now, the Bill and Melinda Gates Foundation is providing three million Swiss francs in support of a joint project by the Swiss water research institute Eawag and the eThekwini water utility in South Africa to develop this approach in a practical way.

The four-year project involves the further development of technical solutions for nutrient recycling from urine. In addition, together with experts from the University of KwaZulu-Natal and ETH Zurich, the participants are investigating logistical solutions for collecting and transporting urine from toilets to treatment plants. Finally, the Swiss water researchers are working with their partners in South Africa to investigate how the production and sale of a fertilizer from urine can economically promote sanitation so that an inexpensive, efficient and widely accepted sanitation system can be established.

Alternatives are urgently needed

The project is based on the realization that alternative concepts to the chain of toilets, alluvial sewers and central wastewater treatment are needed - if only because there is not enough water available in many places. This is particularly urgent if the number of people without access to basic sanitation and safe drinking water is to fall, as called for in the UN Millennium Development Goals. This is because, in addition to endangering the health of the population, inadequate disposal of fecal sludge in many places also jeopardizes drinking water supplies and places a massive burden on aquatic ecosystems. And last but not least, the global demand for fertilizer is so great that interest in local sources of nutrients is growing.

Successful preliminary work in Nepal

Eawag has many years of experience in research into urine source separation, also known as NoMix technology. In 2007, the cross-disciplinary Novaquatis project was completed for this purpose. Since then, Eawag has demonstrated - inter alia in a project in Siddhipur near Kathmandu (Nepal) - that urine processing to produce the phosphorus fertilizer struvite can close regional nutrient cycles and promote awareness of the value of nutrients in urine. The farmers involved also benefit because they have to buy less artificial fertilizer from imported sources. Acceptance of the simple dry toilets with urine source separation was further boosted in Nepal because the 100 or so test families were supported by a local "hygiene committee". www.eawag.ch/stun. "Eawag’s experience with the NoMix technology and cooperation with a very progressive administration have certainly contributed to the fact that our project is now being funded with a total of three million Swiss francs," says process engineer Kai Udert, who is leading the project at Eawag.

Cooperation with innovative water authority

In fact, Swiss water researchers in the South African region of eThekwini around Durban can rely on an innovative administration that has already done significant pioneering work in the field of sanitation. Among other things, water officials have been promoting a range of different dry toilets since 2002. Around 90,000 toilets with separate urine drainage are already in operation - but today the urine is simply seeped away, which creates new problems in the longer term. With nutrient recycling from urine, the aim now is to establish an overall system that is as simple as possible, reduces the cost of sanitation, prevents pollution of water resources and produces a fertilizer for the local market. "This is a completely new way of thinking, not just a small step along an already familiar path," says Kai Udert.