Characterization of aluminium-based water treatment residual for potential phosphorus removal in engineered wetlands

• Published in: Environmental pollution (1987) Vol. 157; no. 10; pp. 2830 - 2836
• Main Authors: Babatunde, A.O., Zhao, Y.Q., Burke, A.M., Morris, M.A., Hanrahan, J.P.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.10.2009; Elsevier
• Subjects: Adsorption; Adsorption capacity; Aluminum; Aluminum - chemistry; Applied sciences; Biological and medical sciences; Biological treatment of waters; Biotechnology; Byproducts; chemical residues; constructed wetlands; Engineered wetlands; Environment and pollution; Exact sciences and technology; extraction; Fundamental and applied biological sciences. Psychology; General purification processes; Industrial applications and implications. Economical aspects; phosphates; phosphorus; Phosphorus - chemistry; Phosphorus removal; physicochemical properties; Pollution; Reuse; sorption isotherms; Surface chemistry; Wastewater treatment; Wastewaters; Water Pollutants, Chemical - chemistry; water pollution; Water Purification - instrumentation; Water Purification - methods; Water Supply - analysis; Water treatment; Water treatment and pollution; Water treatment residual; Wetlands; X-rays; Ireland; Europe; Adsorption capacity; Phosphorus removal; Engineered wetlands; Wastewater treatment; Water treatment residual; Phosphates; Treatment residue; Specific surface area; Phosphorus; Biological purification; Waste management; Flocculation reagent; Artificial medium; Upgrading; Waste reuse; Surface area; Waste water purification; Wetland; Aluminium sulfate
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2009.04.016

Aluminium-based water treatment residual (Al-WTR) is the most widely generated residual from water treatment facilities worldwide. It is regarded as a by-product of no reuse potential and landfilled. This study assessed Al-WTR as potential phosphate-removing substrate in engineered wetlands. Results indicate specific surface area ranged from 28.0 m 2 g −1 to 41.4 m 2 g −1. X-ray Diffraction, Fourier transform infrared and energy-dispersive X-ray spectroscopes all indicate Al-WTR is mainly composed of amorphous aluminium which influences its phosphorus (P) adsorption capacity. The pH and electrical conductivity ranged from 5.9 to 6.0 and 0.104 dS m −1 to 0.140 dS m −1 respectively, showing that it should support plant growth. Batch tests showed adsorption maxima of 31.9 mg P g −1 and significant P removal was achieved in column tests. Overall, results showed that Al-WTR can be used for P removal in engineered wetlands and it carries the benefits of reuse of a by-product that promotes sustainability. Aluminium-based water treatment residual can be used for phosphorus removal in engineered wetlands!