| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1055435 | Journal of Environmental Management | 2016 | 12 Pages |
•Anaerobically digested dairy manure has a high potential for struvite recovery.•Digested dairy manure is rich in ammonium, orthophosphate, and magnesium.•High ionic strength, Ca, and alkalinity hinder struvite formation in dairy manure.•Struvite recovery potential is defined by the least molar activity of struvite ions.•A mix of measures may overcome hindrances of digested manure to struvite formation.
Anaerobically digested dairy manure is rich in ammonium, orthophosphates, and magnesium, indicating a high potential for struvite recovery. Continuous generation of large amounts of dairy manure plus increasing global interest in anaerobic digestion of dairy manure suggest a huge market for struvite production with anaerobically digested dairy manure. However, the complex chemical composition of digested dairy manure presents hindrances to struvite recovery. This review paper assesses the significance and potential of struvite recovery from anaerobically digested dairy manure, identifies the factors hindering struvite recovery, and discusses the methods to overcome hindrances and the measures to improve phosphorus speciation of dairy manure for struvite formation. This paper proposes using “struvite recovery potential” or Pstruvite based on the least molar activity of struvite component ions in addition to “supersaturation ratio” to identify the potential for struvite recovery. The probable hindrances mainly include high Ca2+ concentration and molar activity ratios of Ca2+: Mg2+ and Ca2+: PO43−, high ionic strength, and high alkalinity. Struvite formation and purity is likely a function of all the interfering variables, rather than just a single factor with digested dairy manure. Potential enhancement measures need to be tested for technical and economic feasibility and applicability to various sources of digested dairy manure. This review paper provides guidance to overcoming the hindrances of digested dairy manure to struvite formation.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide
