Title |
Recovery of phosphate and ammonia from wastewater via struvite precipitation using spent refractory brick gravel from steel industry |
ID_Doc |
23587 |
Authors |
Li, DY; Cho, YC; Hsu, MH; Lin, YP |
Title |
Recovery of phosphate and ammonia from wastewater via struvite precipitation using spent refractory brick gravel from steel industry |
Year |
2022 |
Published |
|
DOI |
10.1016/j.jenvman.2021.114110 |
Abstract |
Spent refractory brick (SRB) generated from the steel industry has a high magnesium content. In this study, a procedure was developed to utilize SRB gravels for efficient recovery of phosphate and ammonia from high strength wastewater via struvite (MgNH4PO4 center dot 6H2O(s)) precipitation. Mg2+ and Ca2+ were first leached from SRB gravels using nitric acid solution. Ca2+ in the solution could inhibit struvite precipitation and was sequestered by dosing SO32xe213; to form calcium sulfite (CaSO3(s)). The resulting Mg2+-rich solution was then employed to initiate struvite precipitation for phosphate and ammonia recovery. The optimal precipitation was achieved with a molar ratio of [Mg2+]:[NH3-N]:[PO43-P] = 2:1:2 at pH 9.5. The residual phosphate in the solution can be further removed via the precipitation of calcium phosphate minerals. Overall, 99.6% phosphate and 98.2% ammonia could be recovered and the treated wastewater could meet the discharging standards of ammonia and phosphate. The resulting solids, including calcium sulfite, struvite and calcium phosphate can be potentially used in the cement industry and agriculture sector to achieve sustainable recycle of spent materials. |
Author Keywords |
Magnesium; Calcium; Nutrients; Resource recycle; Circular economy |
Index Keywords |
Index Keywords |
Document Type |
Other |
Open Access |
Open Access |
Source |
Science Citation Index Expanded (SCI-EXPANDED) |
EID |
WOS:000744266900006 |
WoS Category |
Environmental Sciences |
Research Area |
Environmental Sciences & Ecology |
PDF |
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