RT Journal Article
T1 Environmental and Geochemical characterization of alkaline mine wastes from Phalaborwa (Palabora) Complex, South Africa
A1 Gómez Arias, Alba
A1 Yesares Ortiz, María Dolores
A1 Caraballo Monge, Manuel Antonio
A1 Maleke, Maleke
A1 Vermeulen, Danie
A1 Nieto Liñán, José Miguel
A1 Heerden, Esta van
A1 Castillo Hernández, Julio Cesar
AB A detailed characterization of alkaline tailing ponds and waste rock dumps from Phalaborwa Igneous Complex (PIC) South Africa, has been accomplished. The study goes beyond the environmental characterization of mining wastes, offering the first insight towards the recycling of the wastes as alkaline reagent to neutralize acid industrial wastewater. To achieve these aims, tailings and waste rocks were characterized using a combination of conventional, novel and modified Acid Rock Drainage (ARD) prediction methodologies, as well as South African leachate tests, sequential extractions and pseudo-total digestions. The scarcity of Fe-sulphide minerals and the abundance of alkaline minerals indicated that PIC wastes are not ARD producers. The highest neutralization potential was found in the carbonatite rocks and East tailing samples (range between 289 and 801 kg CaCO3 eq/t). According to the National Environmental Management Waste Act (59/2008) of South Africa, tailing ponds and waste rock dumps from PIC classify as non-hazardous (Type 3 waste). The sequential extractions showed that the different fractions from most of the samples would mostly release sulphate and non-toxic elements, such as Ca, Mg, Na and K, which might be a concern if leached in high concentration. In addition, relatively high concentrations of radionuclides, such as U and Th (average of 6.7 and 36.3 mg/kg, respectively) are present in the non-labile fraction of PIC wastes, while the leachable concentrations were always below 0.006 mg/L. Among PIC wastes, East tailing would be the best option as alkaline reagent to neutralize acid wastewater because of its high neutralization potential and non-harmful leachate composition. In general, this study exposes the shortcomings in mine waste characterization, particularly for alkaline mine wastes, and introduces the assessment of potential revalorization as a novel practice in mine waste characterization that, if extended as a regular practice, would facilitate a circular economy approach to the mining industry with its consequent economic and environmental benefits.
PB Elsevier
SN 0375-6742
SN 1879-1689 (electrónico)
SN 1879-1689 (electrónico)
YR 2021
FD 2021
LK https://hdl.handle.net/10272/23233
UL https://hdl.handle.net/10272/23233
LA eng
NO Alba Gómez-Arias, Lola Yesares, Manuel A. Caraballo, Maleke Maleke, Danie Vermeulen, José M. Nieto, Esta van Heerden, Julio Castillo, Environmental and geochemical characterization of alkaline mine wastes from Phalaborwa (Palabora) Complex, South Africa, Journal of Geochemical Exploration, Volume 224, 2021, 106757, ISSN 0375-6742, https://doi.org/10.1016/j.gexplo.2021.106757
NO This work was supported by the Department of Science and Technology (South Africa) through the ERAMIN project of the Horizon2020 (AMDREY-PCIN2015-242-256). It was also partially financed by: UNESCO (UNESCO-IUGS-IGCP-Project 682), Ministerio de Ciencia e Innovacin project MOS, Spain (grant number CGL2016-79204-R), CORFO and Codelco (project CORFO-16PTECME-66524), project CONICYT/PIA AFB180004 and Science Foundation Ireland (grant number 18/IF/6347). Special thanks are due to the staff of Palabora Mining Company and Foskor for their assistance during the sampling. The authors would like to thank the reviewers for their thoughtful comments and efforts towards improving the manuscript
DS Repositorio Institucional de la Universidad de Huelva
RD 13 jun 2026