Ammonium nitrogen removal from slurry-type swine wastewater by pretreatment using struvite crystallization for nitrogen control of anaerobic digestion

Abstract

Precipitation of ammonium together with phosphate and magnesium is a possible alternative for lowering the nitrogen content of wastewater. In this study we examine the removal of ammonium nitrogen and phosphorus from slurry-type swine wastewater containing high concentrations of nutrients by the addition of phosphoric acid along with either calcium oxide or magnesium oxide, which leads to the crystallization of insoluble salts such as hydroxyapatite and struvite. The struvite crystallization method showed a high capacity for the removal of nitrogen when magnesium oxide and phosphoric acid were used as the magnesium and phosphate sources, respectively. When it was applied to swine wastewater containing a high concentration of nitrogen, the injection molar ratio of Mg2+:NH4+:PO4(3-) that gave maximum ammonium nitrogen removal was 3.0:1.0:1.5.

Phosphorus Recovery from Wastewater by Struvite Crystallization: A Review

“…Ammonium removal (ratio 1:1:1 Maekawa et al (1995) Swine wastewater More than 90% Priestley et al (1997) BPR anaerobic digested effluents 98% Altinbaş et al (2002) Anaerobically pre-treated wastewater from 68 to 72% Kim et al (2004)…”

Recovery of ammonium nitrogen from the effluent of UASB treating poultry manure wastewater by MAP precipitation as a slow release fertilizer

“…In recent years, several papers have addressed the recovery of NH 4 + or PO 4 3− as struvite from various types of wastewaters (mostly leachate and piggery wastewaters) such as landfill leachate [12,[20][21][22][23][24], swine wastewater [25][26][27][28], source-separated human urine [29,30], industrial wastewater [13,31], anaerobically pretreated domestic wastewater [32], slaughterhouse wastewater [33], filtered pig manure wastewater [34], anaerobic swine lagoon liquid [11], and supernatant of anaerobically digested sludge [35]. Compared with these studies, Lei et al [36] have emphasized that there is an advantage for applying struvite precipitation process to anaerobic effluents due to predominance of struvite constituent ions, NH 4 + -N and PO 4 3− -P, in the methane fermentation effluent, thereby minimizing the need to add chemicals.…”

Design and Optimization of Fluidized Bed Reactor Operating Conditions for Struvite Recovery Process from Swine Wastewater

“…This finding is in line with earlier studies [24], which observed that struvite was actively formed at pH 9-10. Previous studies also showed that, within the pH range of 8-11 and at a Mg to O-P ratio of over 1.0, the O-P removal from swine wastewater reached around 90% regardless of other operational parameters such as CR and HRT [1,[25][26][27][28], while a pH below 7.5 resulted in a much lower O-P recovery efficiency [11]. Therefore, the response analysis for O-P recovery was not expected to have meaningful results, and its relationship could not be built with the operational parameters.…”