Creating a valuable fertilizer at Marselisborg plant in Aarhus
Phosphorus recovery from wastewater
Without reuse of phosphorus, depletion is foreseen in 100 years from now and the European Commission has classified phosphorus among the 20 “critical materials”.
Technology that contributes to the circular economy and resource recycling
We developed a solution that extracts phosphorus via struvite from wastewater and turns it into a fertilizer.
The heart of Phosphogreen™ process consists injecting magnesium chloride to obtain precipitation-crystallization of struvite. Struvite is then extracted at the bottom of the reactor, washed, drained and dried before packaging.
Mass balance with up to 50% phosphorus recovery
Phosphogreen™ solution was fist implemented in a full-scale at Marselisborg wastewater treatment plant located in Aarhus.
The main reason was to solve an existing problem with struvite scaling in old and new pipes and present sand in digesters. Implementation of phosphorus recovery would eliminate those issues meanwhile increasing a green image of the client’s wastewater plant and its contribution to circular economy.
Total struvite production ranges between 650-800kg per day that can be sold on the market as agricultural fertilizers containing:
- 12,5% phosphorus
- 5,5% nitrogen
- 10% magnesium
with granules sizes between 1 to 3 mm.
SUEZ Phosphogreen™ solution at Marselisborg WWTP
Credit: SUEZ Danmark