Phosphorus recycling as struvite from pig manure. Influence of process parameters
Résumé
Previous studies have shown that it was feasible, at bench scale, to recycle P from pig slurry as mineral fertiliser by a simple acidification/precipitation process. In this study the influence of several parameters on the continuous pilot process designed from the bench scale results were tested. The pH, stirring rate, N/P ratio and solid retention time were the main factors influencing the proportion of struvite in the solid and the crystal size. The P abatement rate was 95-99% both on dissolved and total phosphorus.