The prebiotic relevance of mineral struvite, MgNH4PO4·6H2O, was studied experimentally as a phosphorylating reagent and, theoretically, to understand the geochemical requirements for its formation. The effectiveness of phosphorylation by the phosphate mineral, monetite, CaHPO4, was also studied to compare to the efficiency of struvite. The experiments focused on the phosphorylation reactions of...

Urolithiasis accounts for 15% to 23% of cases of feline lower urinary tract disease (FLUTD), with struvite uroliths occurring more frequently, followed by calcium oxalate, ammonium urate, cystine, and xanthine calculi. In this clinical evaluation, we tested the efficacy of a commercially available nutraceutical diet in 33 cats affected by struvite uroliths. Results clearly indicated a significa...

The present review provides an understanding of principles of struvite crystallisation and examines the techniques and processes experimented to date by researchers at laboratory, pilot and full scale to maximise phosphorus removal and reuse as struvite from wastewater effluents. Struvite is mainly known as a scale deposit causing concerns to wastewater companies. Indeed struvite naturally occu...

Introduction Uroliths are concretions formed in the urinary tract. These can be problematic humans and companion animals such as cats. Magnesium ammonium phosphate (struvite) calcium oxalate (CaOx) most common forms of uroliths. The relative supersaturation (RSS) is a risk index crystal formation. Here, an updated program for calculating RSS, EQUIL-HL21, was used to detect differences RSS value...

Process of struvite (MgNH4PO4·6H2O) precipitation is a promising method for phosphorus recycling. The use of cheap magnesium ore for precipitation struvite as phosphate recovery has been examined. The optimal conditions for precipitation are pH 9.0 and Mg: 4 NH  : 4 PO  molar ratio 1.1:30.7:1. Linear correlation of experimental data is in qualitative agreement with modelling calculation. Surf...

OBJECTIVE To investigate the struvite precipitation under constant and non-constant pH conditions and to test a stainless steel device under different operating regimes to maximize the recovery of struvite. METHODS The molar ratio of NH4+: Mg2+: PO4(3-) was adjusted to 1: 1.2: 1.2 and pH was elevated to 9.0. The absorbance measurement was used to trace the process of struvite crystallization....

Recovering struvite from dairy manure has consistently posed problems for researchers. This study separated solids from anaerobically digested dairy manure using a filtration system. Filtrate was rich in free magnesium (160 to 423 mg/L), ammonium (320 to 1800 mg N/L) and orthophosphate (93 to 332 mg P/L). High concentrations of free calcium (128 to 361 mg/L) and alkalinity (3309 to 6567 mg/L as...

In the present study, struvite decomposition was performed by air stripping for ammonia release and a novel integrated reactor was designed for the simultaneous removal and recovery of total ammonia-nitrogen (TAN) and total orthophosphate (PT) from swine wastewater by internal struvite recycling. Decomposition of struvite by air stripping was found to be feasible. Without supplementation with a...

All the phosphate rock Japan needs must be presently imported from abroad because the country has no subterranean phosphorous resources. Therefore, there is a need to accelerate the development of and establish the technologies for phosphorous recovery from waste and wastewater. Swine wastewater has a high potential for phosphorous recovery in Japan. A reactor for removing and recovering phosph...

The presence of white deposits in specific areas of wastewater treatment plants is generally the consequence of the spontaneous formation of a mineral called struvite. Struvite forms when the levels of phosphate, ammonium and magnesium naturally available in wastewater effluents reach a minimum molar ratio 1:1:1 under specific conditions of pH, temperature and mixing energy. Originally regarded...