Effect of low-intensity magnetic fields on constructed wetland mesocosms treating chromium wastewater

CIM Journal, Vol. 6, No. 1, 2015, pages 59-65
A. Rodriguez-Prado
Independent Consultant, Saskatoon, Saskatchewan, Canada
http://dx.doi.org/10.15834/cimj.2015.2
Abstract Magnetic fields affect the growth of cultured cells and plants; however, limited information exists about their effects on vegetation performing environmental remediation. Constructed wetland mesocosms treating hexavalent chromium (Cr(VI)) wastewater exposed to low-intensity magnetic fields (60 Hz, 56.5 × 10−6 Tesla) produced 100% more biomass than the unexposed control. Nonetheless, they removed only 43 ± 27% of Cr(VI), compared to 60 ± 21% for the control. A Cr(VI) reduction expression was developed as a function of the magnetic field. The design and operation of constructed wetlands to treat mining wastewater can be corrected for magnetic field effects.
Keywords: Aquatic plant growth, Constructed wetlands, Helmholtz coils, Hexavalent chromium (Cr(VI)), Magnetic fields, Wastewater treatment
Résumé Les champs magnétiques affectent la croissance des cellules et des plantes cultivées; toutefois, il existe peu d’information quant à leurs effets sur la végétation utilisée à des fins d’assainissement environnementale. Les mésocosmes des marais artificiels traitant des eaux usées, contenant du chrome hexavalent (Cr(VI)), exposés à des champs magnétiques de faible intensité (60 Hz, 56,5 × 10−6 Tesla) ont produit 100 % plus de biomasse que le contrôle non exposé. Néanmoins, ils n’ont enlevé que 43 ± 27 % du Cr(VI), comparativement à 60 ± 21 % pour le contrôle. Une expression de réduction du Cr(VI) a été développée en tant que fonction du champ magnétique. La conception et l’exploitation de marais artificiels pour traiter les eaux usées des mines peuvent être adaptées pour tenir compte des effets des champs magnétiques.
Mots-Clé Bobines d’Helmholtz, champs magnétiques, chrome hexavalent (Cr(VI)), croissance de plantes aquatiques, marais artificiels, traitement des eaux usées
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