Precipitation of struvite using MgSO4 solution prepared from sidestream dolomite or fly ash

• DOI: 10.1016/j.heliyon.2022.e12580
• Publication Date: 2022-12-25T14:34:06Z
• Authors: Janne Pesonen; Fien Janssens; Tao Hu; Ulla Lassi; Sari Tuomikoski
• Keywords: Struvite

Struvite (NH4MgPO4∗6H2O) is a slow-release fertilizer produced from phosphorus and nitrogen-containing wastewater in the presence of Mg salts. Commercial salts are single most significant cost struvite precipitation. In this study, H2SO4 formed as an industrial sidestream was used to prepare MgSO4 solution waste dolomite (DOL) fly ash (FA). then precipitate synthetic (NH4)2HPO4 actual process waters. The best results were obtained with real waters where over 99% phosphate about 80% ammonium removals achieved both solutions after 30 min reaction time. A higher molar ratio between P improved removal efficiency, especially DOL-based solutions; however, it had no practical effect on removal. content precipitates 75.49% FA-based chemical 60.93% chemical; other valuable nutrients (Ca, K, S, Fe, Mn, Cl) captured precipitates. indicate that sidestream-based reagents perform well precipitation could be fertilizers.