Aluminum-Based Water Treatment Residue Reuse for Phosphorus Removal

Water

Lai Yoke Lee¹  Bibin Wang²  Huiling Guo²  Jiang Yong Hu²  Say Leong Ong² 

[1] Centre for Water Research, Department of Civil & Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, 117576, Singapore;

关键词: phosphorus removal;    water treatment residue;    bioretention system;    filtration media;    secondary treated effluent;   

DOI  :  10.3390/w7041480

来源: mdpi

【 摘 要 】

Aluminum-based water treatment residue (Al-WTR) generated during the drinking water treatment process is a readily available recycled material with high phosphorus (P) adsorption capacity. The P adsorption capacity of Al-WTR generated from Singapore’s water treatment plant was evaluated with reference to particle size range, adsorption pH and temperature. Column tests, with WTR amendments in sand with and without compost, were used to simulate the bioretention systems. The adsorption rate decreased with increasing WTR sizes. Highest P adsorption capacity, 15.57 mg PO₄³⁻-P/g WTR, was achieved using fine WTR particles (>50% particles at less than 0.30 mm). At pH 4, the contact time required to reduce effluent P concentration to below the detectable range was half compared with pH 7 and 9. The adsorption rate observed at 40 ± 2 °C was 21% higher compared with that at 30 ± 2 °C. Soil mixes amended with 10% WTR and compost were able to maintain consistently high (90%) total phosphorus (TP) removal efficiency at a TP load up to 6.45 g/m³. In contrast, TP removal efficiencies associated with columns without WTR amendment decreased to less than 45% as the TP load increased beyond 4.5 g/m³. The results showed that WTR application is beneficial for enhanced TP removal in bioretention systems.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.