Phosphorus Recovery from Sludge Liquor Using Struvia™ Technology

Phosphorus recovery from sewage sludge liquor using bio-acidification and Struvia™ technology in a pilot plant in Lille, France, achieves up to 75% recovery. The process involves anaerobic fermentation with carbohydrates to solubilize phosphorus, followed by struvite precipitation. The resulting granular struvite, with particle sizes of 200–500 µm, has low organic carbon (<1–2%) and low metal content, making it suitable as a fertilizer or feedstock. The plant processes 4 tons/day of thickened sludge, yielding 9–10 kg/day of phosphorus-rich product. Led by IRSTEA and Véolia Environnement, the project is licensed under CC BY.