Phosphorus Recovery from Sewage Sludge as Struvite

Environmental legislation on waste management coupled with the potential for nutrient recovery are key factors encouraging use of advanced treatment technologies to manage biosolids waste. In this context, phosphorus from sewage sludge treated by a wet oxidation (WO) process was carried out in work. High organic matter (up 85% COD) and total solids content 75%) removal values were achieved WO at elevated temperature 300 °C) pressure 200 bar) conditions. The liquid solid fractions found effluent contain high amounts that can be recovered. This research aims maximize its both fractions. effluent, recovered 90 mg P/L) chemical precipitation as struvite (MgNH4PO4∙6 H2O), slow-release fertilizer. case, P recoveries greater than 95% achieved. Additionally, fraction, analyzed after filtration drying (68 P/gsolid), acid leaching, obtaining up 60% recovery. All extracted orthophosphate form.