Granulation and calcination of alum sludge for the development of a phosphorus adsorbent: From lab scale to pilot scale

JOURNAL OF ENVIRONMENTAL MANAGEMENT

卷:279

Article

Everaert, Maarten¹  Bergmans, Jef¹  Broos, Kris¹  Hermans, Benjamin²  Michielsen, Bart¹ 

[1] Flemish Inst Technol Res VITO, Unit Sustainable Mat Management, Boeretang 200, B-2400 Mol, Belgium

[2] De Watergrp, Vooruitgangstraat 189, B-1030 Brussels, Belgium

关键词: Alum sludge;    Calcination;    Drinking water production;    Granulation;    Phosphorus adsorption;    Water treatment;   

DOI  :  10.1016/j.jenvman.2020.111525

来源: Elsevier

【 摘 要 】

Alum sludge, an Al-oxyhydroxide rich waste product from water treatment practices, has the potential to be valorized as a P adsorbent material. However, several challenges currently prevent its application as an adsorbent in industrial setting, i.e. a limited P adsorption capacity due to saturation by organic matter and a fine nature resulting in percolation problems in adsorption bed setups. In this study, granulation and subsequent calcination of alum sludge were proposed to overcome these issues and to improve the P adsorption properties of alum-based adsorbent (ABA) materials. The effect of calcination temperature on the physicochemical properties of granular material was examined using X-ray diffraction, mass-spectroscopy coupled thermogravimetric analysis, Fourier-transform infrared spectrometry and specific surface area analysis, combined with density and crushing strength measurements. The ABA material obtained at 550 ?C showed superior P adsorption properties and, therefore, this material was selected for further P adsorption testing and characterization (scanning electron microscopy and sieving). Batch P adsorption tests showed that this material had a maximum P adsorption capacity of 7.27 mg-P g(-1). Kinetic adsorption tests determined the effect of the solid-to-liquid ratio and the granule particle size on the P removal. Finally, the performance of the ABA-550 material was tested in a pilot-scale adsorption setup, using a surface water stream (0.47 mg-P L-1) at a flow rate of 200 L h(-1). During the test, the P removal efficiency always exceeded 86%, while the material maintained its structural stability. The results of this study illustrate the potential of granulated/calcined ABA materials for P adsorption, paving the way for the industrial application of this novel, sustainable P removal technology.

【 授权许可】

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