Related Experiment Video
Updated: Feb 18, 2026

Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent
Published on: February 21, 2017
Alkaline solubilization of excess mixed sludge and the recovery of released phosphorus as magnesium ammonium
De-Chao Xu1, Cong-Qiang Zhong1, Kui-Hao Yin1
1Shenzhen Academy of Environmental Sciences, Shenzhen 518001, China; State Environmental Protection Key Laboratory of Drinking Water Source Management and Technology, Shenzhen 518001, China; Shenzhen Key Laboratory of Emerging Contaminants Detection & Control in Water Environment, Shenzhen 518001, China.
Abstract:
The alkaline solubilization of excess mixed sludge was investigated and subsequently the released phosphorus was recovered as magnesium ammonium phosphate (MAP). Considerable and rapid release of glycogen and protein was encountered after alkaline addition into the sludge. Only 45.0% of sludge cells were destructed after 240 min treatment in R1 while the corresponding ratio was 96.1% in R3 according to the release of DNA. Non-apatite inorganic phosphorus (NAIP) in the alkaline treated sludge decreased due to the dissolution of Al(OH)3 and AlPO4, which was the dominant reason for phosphorus release. Soluble orthophosphate (SOP) in the supernatant of alkaline treated sludge could be recovered quickly with the recovery efficiency of 84.6% within 5 min and about 53-55% of P participated in MAP reaction, producing large amounts of acicular crystals.
More Related Videos
Related Concept Videos
Factors Affecting Solubility
Washing, Drying, and Ignition of Precipitates
Coagulation
Qualitative Analysis
For instance, group IV...
Extraction: Advanced Methods
The Phosphorus Cycle

