Struvite is known to form a hard scale in specific areas of wastewater treatment plants. Besides causing problems; struvite can also be used as a fertilizer. Good and reliable solubility data is essential for controlling the crystallisation of struvite. One of the important factors that affect the crystallisation of struvite is solution pH. Therefore, this study was undertaken to investigate in...

Mineral speciation of struvite family crystals precipitated in a synthetic wastewater containing Mg: NH : PO3 (MAP) ions were determined in the study. The pH levels by KOH addition and MAP ratios were set up to be the parameter dependence on struvite family crystals precipitation. The Rietveld analysis of XRPD pattern confirmed a mixed product of struvite, struvite-(K) and newberyite precipitat...

Struvite precipitation proved to be an effective method of ammonia removal from the landfill leachate from two separate sources. Batch tests for precipitating struvite yielded several different chemical combinations that were effective at removing ammonia from leachate. The struvite precipitate samples were quite heterogeneous in composition, containing a mixture of short and thick crystals, el...

BACKGROUND Formation of struvite stones is associated with urinary tract infection by urease-producing bacteria. Biogenic crystal growth in natural and synthetic materials is regulated by the action of inhibitors, ranging from small ions, molecules to large macromolecules. MATERIALS AND METHODS We report the dynamics of in vitro crystallization of struvite in presence of vitamin C in syntheti...

The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions addition are presented. Continuous reaction crystallization of struvite MgNH4PO4 × 6H2O ran both under stoichiometric conditions and at 20% excess of magnesium ions (pH 9,  900 s). ...

Formation of urinary stone is a serious and debilitating problem throughout the world. In the present study, the inhibitory effect of aqueous extract of root of Rotula aquatica was investigated against struvite crystals (one of the components of urinary stone) grown in vitro using single diffusion gel growth technique. For setting the gel, sodium metasilicate solution (specific gravity 1.05) an...

BACKGROUND:  Struvite crystals (Magnesium Ammonium Phosphate) are one of the most common causes of urolith formation in cats. Presence of these crystals in urea leads to urinary obstruction and idiopathic cystitis. The prevalence of urinary crystals has increased in recent years, thus there has been a growing interest in development of noninvasive, fast responsive therapies. Vitamin C is a safe...

An energy efficient method of concurrent hydrogen gas and struvite (MgNH(4)PO(4)·6H(2)O) production was investigated based on bioelectrochemically driven struvite crystallization at the cathode of a single chamber microbial electrolysis struvite-precipitation cell (MESC). The MESC cathodes were either stainless steel 304 mesh or flat plates. Phosphate removal ranged from 20% to 40%, with higher...

A sustainable way to recover phosphorus (P) in swine wastewater involves a preliminary step of P dissolution followed by the separation of particulate organic matter. The next two steps are firstly the precipitation of struvite crystals done by adding a crystallization reagent (magnesia) and secondly the filtration of the crystals. A design of experiments with five process parameters was set up...

The crystallisation of struvite is one means of removing phosphate (and nitrogen) from nutrient-rich wastewater. As with all crystallisation processes, the growth rate of the crystals and its dependence on supersaturation is of considerable interest in designing processing equipment. Modelling of struvite solubility using the computer package MINTEQA2 showed that struvite exhibits a minimum sol...