Nitrogen and phosphorus recovery from anaerobic co-digestion…struvite precipitation
In the ongoing efforts to extend appropriate sanitation to the millions in the world lacking it, it benefits all to show that the byproduct of sanitation is not waste, but a valuable agricultural resource. Some even call it the new gold. This tangential research below is important in helping get that gold and getting to that goal.
New research by
- Y Dilsad Yilmaze – Civil and Environmental Engineering Department, Villanova University, Villanova, PA, USA
- Goksel Demirer – Department of Environmental Engineering, Middle East Technical University, Ankara, Turkey
Nitrogen and phosphorus recovery from anaerobic co-digestion residues of poultry manure and maize silage via struvite precipitation
Anaerobic digestion is commonly used for the stabilization of agricultural and animal wastes. However, owing to the stringent environmental criteria, anaerobic digester effluents need to be further treated to reduce nutrient loads to the receiving water bodies. Struvite precipitation is one of the promising techniques applied for this purpose. Yet, in the majority of cases, struvite precipitation is only applied to the liquid phase of anaerobic digester effluents. This study investigated the recovery of nutrients from both the liquid and the solid phases of the phase-separated effluent of a full-scale biogas plant co-digesting poultry manure and maize silage. Struvite precipitation in the liquid phase led to 72.1% and 95.1% average removal efficiencies of ammonium-nitrogen (NH4-N) and orthophosphate respectively. Changing the external phosphorus source did not make any statistically significant difference in nutrient removal. An acidic phosphorus-dissolution process was applied to the solid phase sample to obtain a phosphorus-enriched solution. More than 90.0% of both NH4-N and PO4-P were recovered from the phosphorus-enriched solution with the amendments of magnesium and phosphorus. In the experiments performed without any addition of external magnesium- and phosphorus-containing chemicals, almost complete (99.6%) PO4-P recovery and partial (14.6%) NH4-N recovery were obtained. The results of this study could contribute to the understanding of nutrient recovery from anaerobic digestion residues of manure and agricultural wastes by struvite precipitation.
Side note while WASHLink appreciates the above efforts, we appeal for more researchers to seek out open access scientific and scholarly journals to publish their work. more on OA by an example
- Anaerobic digestion tabled in Franklin (franklinmatters.org)
- UK: 60,000 TPA anaerobic digestion biogas plant approved in Yorkshire (vernetblog.wordpress.com)
- Anaerobic digester for electricity, fertiliser production (vanguardngr.com)
- $20 million program would send chicken bones, pizza boxes to Madison biodigester (host.madison.com)