Master’s thesis proposal – Comparison of different urine-based fertilisers

Background

Urine is an important resource of crop nutrients, actually having a potential economic value of about three times higher than the nutrients that can be utilised from sludge from conventional wastewater treatment plants, since 80% of the nitrogen and 60% of both the phosphorus and the potassium in the wastewater origins from the urine. Therefore, in new city developments close to existing sewers, a good way to increase nutrient recovery from municipal wastewater is to install urine separation systems.

Direct application of human urine as a fertiliser is common practice in many rural areas worldwide. However, direct recycling from urban areas is more complicated. For example, stored urine has a pungent smell and is prone to N losses due to ammonia volatilization, the high water content renders transport to cropping regions costly, and undesired constituents (e.g. pathogens, micropollutants such as synthetic hormones, pharmaceuticals, and their metabolites) pose a health risk to farmers and consumers. Different treatment technologies for stabilisation, volume reduction and removal of health risks ends up with different fertiliser products.

Aim
The main aim of the Master´s thesis is to compare three different types of urine fertilisers with a conventional mineral fertiliser in growth experiments.

Method

The experiments will be performed in a greenhouse at the Swedish University of Agricultural Sciences in Alnarp. The three different types of urine fertilisers are a non-diluted stored urine, a urine dry powder and, Aurin, a concentrated urine fertiliser that is already on the Swiss market.

When?

Spring 2017

Supervisors
Sammar Khalil, assistant professor, Swedish University of Agricultural Sciences (SLU), sammar.khalil@slu.se

David Gustavsson, research leader, Sweden Water Research, david.gustavsson@vasyd.se