Swedish experiences with urine separating systems

Urine separating wastewater systems, where urine is collected and used as a fertiliser, could be a strategy to achieve a high degree of nutrient recycling from human waste to agriculture. The main argument for this is the fact that human urine contains the highest percentage of nutrients in human waste. About 3000 urine-separating water closets have been installed in Sweden. In this paper we describe experiences with urine separating system. Further, the actual utilisation of urine in agriculture and development of risk-assessment guidelines concerning the hygiene of stored urine are of importance. Transportation of large volumes of urine to agriculture can cause a negative environmental impact, however, recent research has shown that it is possible to dewater urine through drying techniques without excessive lossess of nitrogen.