Recently, many methods for treatment and volume reduction of collected yellow water have been studied. One method is dewatering by evaporation with and without nitrification and freeze concentration (Gulyas, 2004). By freezing, it is possible to concentrate 80 % of nitrogen and phosphorus in 25% of the original volume (Ban et al., 1999). By nitrification in combination with drying, it is possible to concentrate over 70 % of the nitrogen in 10 % of the original volume (Hellström and Johansson, 1999). The production of Isobuthylaldehyde-di-urea IBDU and ammonia water from urine is possible. Urea can be converted to IBDU only after concentrating urine. With air stripping and absorption ammonificated urine can be treated very effectively and a solution of 10 % w/w of ammonia can be obtained (Behrendt et al., 2002). These methods could be beneficial, when a larger volume of urine solution has to be transported a long way to the agriculture farm. However, these methods have been investigated only in small scale so far.