Phosphorus Recovery and Bioavailability from Chemical Extraction of Municipal Wastewater Treatment’s Waste Activated Sludge: A Case of Bangkok Metropolis, Thailand
Issued Date
2022-07-01
Resource Type
ISSN
16865456
eISSN
24082384
Scopus ID
2-s2.0-85132120308
Journal Title
Environment and Natural Resources Journal
Volume
20
Issue
4
Start Page
369
End Page
378
Rights Holder(s)
SCOPUS
Bibliographic Citation
Environment and Natural Resources Journal Vol.20 No.4 (2022) , 369-378
Suggested Citation
Khaing K.T., Polprasert C., Mahasandana S., Pimpeach W., Patthanaissaranukool W., Polprasert S. Phosphorus Recovery and Bioavailability from Chemical Extraction of Municipal Wastewater Treatment’s Waste Activated Sludge: A Case of Bangkok Metropolis, Thailand. Environment and Natural Resources Journal Vol.20 No.4 (2022) , 369-378. 378. doi:10.32526/ennrj/20/202200024 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/84699
Title
Phosphorus Recovery and Bioavailability from Chemical Extraction of Municipal Wastewater Treatment’s Waste Activated Sludge: A Case of Bangkok Metropolis, Thailand
Author's Affiliation
Other Contributor(s)
Abstract
This study evaluated the extractability and bioavailability of Phosphorus (P) recovered from waste activated sludge (WAS) so as to reduce dependence on the import of non-renewable P resources. P extraction was carried out using sulfuric acid (H2SO4). A response surface methodology was used to optimize conditions for the chemical leaching of WAS. The results showed the optimum condition for leaching WAS with 0.1 mol/L H2SO4 for 30 min, resulting in 97% P released. The efficiency of P recovery by P precipitation was associated with pH value and Mg:P. At pH 7, 9, and 11, P recovery was 92, 92, and 91% with uncontrolled Mg and 93, 93, and 92% with sea salt (Mg:P, 2:1), respectively. However, the yield of the produced struvite was much lower compared with that of added sea salt. From elemental analysis, the yield of struvite precipitated at pH 9 of Mg:P, 2:1 was about 26%, and the total P content of the precipitate was 12%. Available P was almost 80% after 35 days of operation, which was higher than that of commercial fertilizers. Results of this study are expected to provide fully comprehensive information to decision-makers regarding the suitability of implementing P-composite matter recovered from WAS. This will also help close the loop of the P cycle for food cultivation in the human ecosystem.