Work

Recovery of phosphate from sludge in fecal sludge treatment plants using gypsum waste

Year: 2025
Type: article
Abstract: This study evaluates the use of industrial gypsum waste as a seed material for phosphate recovery from fecal sludge treated in Fecal Sludge Treatment Plants (FSTPs). The objective is to assess the effects of pH and agitation speed on the quantity of recovered phosphate crystals. Industrial gypsum is compared with commercial-grade gypsum, and calcium dosages are based on stoichiometric requirements. Experimental conditions include pH levels of 7, 8, and 9, and agitation speeds of 100, 120, and 150 rpm, with pH adjusted using NaOH or H2SO4. Phosphate was measured using spectrophotometry following the extraction of sludge into a phosphate-rich solution. Extraction at pH 2 for 5 hours yielded recovery efficiencies of at least 65%. The results show that industrial gypsum waste supports crystal formation and achieves phosphate removal efficiencies exceeding 98% at pH 8–9 and stirring speeds of 100–150 rpm. Compare to amount of crystal formed, this research results suggest that best choice is reactor LG8-120, with phosphate removal 98.79% and crystal formed were 0.9903 grams. These findings suggest that industrial gypsum waste is a cost-effective and sustainable alternative for phosphate recovery, offering potential for nutrient recycling in resource-limited settings.
Language: English
Open Access status: green
OpenAlex ID: W7117118634
FWCI:
Cites:
Cited by:
Related to: