Removal of strontium from drinking water by conventional treatment and lime softening in bench-scale studies

WATER RESEARCH

卷:103

Article

O'Donnell, Alissa J.¹  Lytle, Darren A.²  Harmon, Stephen²  Vu, Kevin³  Chait, Hannah⁴  Dionysiou, Dionysios D.¹ 

[1] Univ Cincinnati, Dept Biomed Chem & Environm Engn, 601 Engn Res Ctr, Cincinnati, OH 45221 USA

[2] US EPA, ORD, NRMRL, WSWRD, 26 W Martin Luther King Dr, Cincinnati, OH 45268 USA

[3] Macaulay Honors Coll City Coll New York, Dept Civil Engn, 160 Convent Ave, New York, NY 10031 USA

[4] Univ Illinois, Dept Chem & Biomol Engn, 600 S Matthews Ave, Urbana, IL 61801 USA

关键词: Strontium;    Drinking water;    Coagulation;    Lime softening;    Jar test;   

DOI  :  10.1016/j.watres.2016.06.036

来源: Elsevier

【 摘 要 】

The United States Environmental Protection Agency Contaminant Candidate List 3 lists strontium as a contaminant for potential regulatory consideration in drinking water. Very limited data is available on strontium removal from drinking water and as a result, there is an immediate need for treatment information. The objective of this work is to evaluate the effectiveness of coagulation/filtration and lime soda ash softening treatment methods to remove strontium from surface and ground waters. Coagulation/filtration jar test results on natural waters showed that conventional treatment with aluminum and iron coagulants were able to achieve only 12% and 5.9% strontium removal, while lime softening removed as high as 78% from natural strontium-containing ground water. Controlled batch experiments on synthetic water showed that strontium removal during the lime-soda ash softening was affected by pH, calcium concentration and dissolved inorganic carbon concentration. In all softening jar tests, the final strontium concentration was directly related to the initial strontium concentration and the removal of strontium was directly associated with calcium removal. Precipitated solids showed well-formed crystals or agglomerates of mixed solids, two polymorphs of calcium carbonate (vaterite and calcite), and strontianite, depending on initial water quality conditions. X-ray diffraction analysis suggested that strontium was likely incorporated in the calcium carbonate crystal lattice and was likely responsible for removal during lime softening. (C) 2016 Published by Elsevier Ltd.

【 授权许可】

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