Membrane Filtration Pretreatment Preceding Struvite Precipitation

The ability of Microfiltration (MF) and Ultrafiltration (UF) technique for separation of organic matter in treatment of nutrient rich fluids is investigated in the study. Such separation is of great importance in case of performing magnesium-ammonium phosphate hexahydrate (struvite) precipitation as the struvite yield depends negatively on organic matter content. The advantage of cross-flow UF in separating the particulate organic matter and soluble phosphorus (P) was proved. Such a process allows COD removal rates over 99 %, while the P in permeate was kept high enough to perform a successful P precipitation as struvite