Urine contains valuable nutrients like ammonium and phosphate which we flush away as waste trough the toilet. During the purification of waste water, 70% of the energy is used for the removal of nitrogen/ammonium and phosphate. Ammonium is broken down to nitrogen during wastewater treatment and discharged into the environment. Phosphate is bound by bacteria in wastewater treatment plants and converted into sludge. The sludge will be burned as waste, while phosphorous is mined constantly to produce fertilizer and recovering phosphorus from mines is finite.
Wetsus investigates possibilities to recover nutrients from wastewater in order to establish a circular economy. From nutrients in urine we can make a fertilizer; struvite. Struvite is a mineral composed from ammonium, phosphate and magnesium and can be easily made from urine.
In this toolkit the students will learn about the importance of resource recovery (module 1), make their own struvite from urine (module 2), determine the concentration (module 3). In an extra module (module 4) they can create an experimental design to test their struvite or different recipes/sources for struvite.