Use of concentrate water from seawater desalination plant as magnesium sources for struvite formation by using anaerobically digested effluent of swine wastewater

Abstract

Young Park (2016): Use of concentrate water from seawater desalination plant as magnesium sources for struvite formation by using anaerobically digested effluent of swine wastewater, Desalination and Water Treatment, A B S T R A C TAlthough struvite crystallization has been proven an effective process to recover nutrients from wastewater, this method has not been used widely because of the cost of the raw chemicals, such as magnesium chloride, required as supplements. In this study, in view of the high cost of supplementing magnesium, reject water from a seawater reverse osmosis process was investigated as a potential source of magnesium. The magnesium was used in the nutrient recovery process, by which struvite crystallization was performed from the anaerobically digested effluent of swine wastewater. The results of all the experiments were positive, indicating that struvite formation was successfully performed from the effluent, using the concentrate water as a magnesium source. Removal efficiencies of up to 94.5% for phosphate and 12.7% for ammonium were achieved under normal operating conditions. Seed materials were successfully used as nucleation sites to enhance the purity of the struvite and the crystal size. The removal efficiencies of phosphate and ammonia could be improved up to 97 and 84%, respectively, by adding phosphate and seed materials.

Changes to Struvite Growth and Morphology as Impacted by Low Molecular Weight Organics

“…The presence of nondiscrete dissolved organic matter (DOM) in LWE is known to hinder the struvite formation process, which is commonly carried out at optimal pH 9–10. − Several approaches are known to mitigate these hindrances to struvite recovery from LWE through DOM removal from the dissolved phase by flocculation, , osmosis/filtration, , and digestion. , In contrast to hindrance from non-descript DOM such as humic substances to struvite growth, ,, negatively charged low molecular weight (LMW) organics such as phenols and carboxylic acids promoted nucleation and growth of struvite in simulated LWE. , Additional research found that adding a negatively charged soluble short peptide labeled shADP5 (short human-derived amelogenin-derived peptide 5, 1736.8 g mol –1 ) to simulated wastewater (SWW) also increased the struvite precipitation rate. This study evaluated the relationship between the ionic charge of the dissolved LMW organics benzylamine, benzoate, and toluene to struvite growth rates and morphology in SWW.…”

“…16,17 The presence of nondiscrete dissolved organic matter (DOM) in LWE is known to hinder the struvite formation process, which is commonly carried out at optimal pH 9− 10. 18−22 Several approaches are known to mitigate these hindrances to struvite recovery from LWE through DOM removal from the dissolved phase by flocculation, 23,24 osmosis/ filtration, 25,26 and digestion. 27,28 In contrast to hindrance from non-descript DOM such as humic substances to struvite growth, 13,18,29 negatively charged low molecular weight (LMW) organics such as phenols and carboxylic acids promoted nucleation and growth of struvite in simulated LWE.…”