Nitrogen and phosphorus recovery from hemodialysis wastewater to use as an agricultural fertilizer.

INTRODUCTION: Hemodialysis wastewater contains high concentrations of ammonia nitrogen and phosphorus. Recovery of these nutrients as soil fertilizers represents an interesting opportunity to ensure a sustainable fertilizer supply.

METHODS: In this paper, a simple method for recovering phosphorous and nitrogen as crystalline struvite [MgNH4 PO4 ·6H2 O] is presented. An integrated cost model is also presented in order to create a positive business case.

RESULTS: Recovery rates in form of struvite of 95% of PO4 3- -P and 23% of NH4 + -N were achieved with a profit.

CONCLUSION: To the best of our knowledge, this paper is the first to study the recovery of these naturally occurring minerals from hemodialysis wastewater. This offers great potential for the valorization of this type of wastewater.