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Updated: Feb 12, 2026
10:49
Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading
Published on: March 6, 2014
17.8K
Use of solid phosphorus fractionation data to evaluate phosphorus release from waste activated sludge
S P Pokhrel1, M W Milke1, R Bello-Mendoza1
1Department of Civil and Natural Resources Engineering, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
Waste Management (New York, N.Y.)
|March 26, 2018
Summary
Waste activated sludge (WAS) is a key phosphorus (P) source. Optimal conditions for P recovery from WAS involve low pH and high temperatures, enhancing P solubilization.
Area of Science:
- Environmental Science
- Environmental Chemistry
- Water Treatment
Background:
- Waste activated sludge (WAS) contains significant amounts of phosphorus (P), a valuable nutrient.
- Phosphorus recovery from WAS is crucial for resource management and preventing eutrophication.
- Understanding P speciation in WAS is essential for developing efficient recovery strategies.
Purpose of the Study:
- To investigate phosphorus speciation and solubilization in waste activated sludge.
- To determine the effects of pH and temperature on phosphorus release from WAS.
- To identify optimal conditions for maximizing phosphorus recovery from WAS.
Main Methods:
- Phosphorus speciation analysis under anaerobic conditions.
- Batch tests conducted at varying pH (4, 6, 8) and temperatures (10, 20, 35°C).
- Measurement of aqueous phosphorus and application of a solid phosphorus extraction protocol.
Main Results:
- Maximum total phosphorus solubilization (51%) achieved at pH 4 and 35°C within 22 days.
- Approximately 50% of total phosphorus solubilized within 7 days under optimal conditions.
- Low pH (4) significantly enhanced the release of apatite inorganic P and non-apatite inorganic P (including microbial polyphosphate).
- Organic phosphorus was found to be less readily released from WAS.
Conclusions:
- Phosphorus recovery from waste activated sludge is feasible and influenced by environmental conditions.
- Low pH and elevated temperatures are key factors for maximizing phosphorus solubilization and recovery from WAS.
- Fractionation analysis provides critical insights for designing efficient phosphorus recovery processes from WAS.
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