Crystallization of struvite in the presence of calcium ions: Change in reaction rate, morphology and chemical composition

Ammonium, phosphorus, and potassium from wastewater treatment with a coexisting ion of calcium may be recovered simultaneously through struvite struvite-(K) crystallization. This paper presents the quantitative assessment impact ions on kinetics crystallization those crystals. Initial solutions containing dose levels Ca2+ pH 9 were set up for experiments in stirred laboratory at ambient temperature. According to reduction data, observed precipitation followed two steps; first step (0–3 min) second (3–60 which linear regression analysis both kinetic data fit first-order rate constants. In absence calcium, computed constants are respectively 2.568 h−1 stage 1.548 stage. The increased Ca (Ca/Mg > 0.5), lengthened multiphase Mg Ca-phosphates. Accordingly, had negative effect morphology, purity, quantity final crystalline product. understanding how affects reliably improves knowledge about controlling recovery products.