Abstract
The impact that mining has on the environment is becoming an ever increasing problem all over the world. South Africa, Brazil and India are main producers of various valuable resources such as for example iron ore, platinum, gold and coal, of which coal and platinum mining will be discussed in this paper. Dumping of ash, waste and discards, result in the formation of acid mine drainage (AMD) due to the high sulphur content of the coal and the waste products. The main Fe-S-bearing minerals in the coals investigated were pyrite, jarosite and ferrous sulphate, a weathering product of pyrite. In the ash produced due to combustion or gasification of the coal, the main Fe-constituents are Fe2+,3+ glass (≈ 30%) and hematite (70%). The amorphous phase of the sample was composed mainly of SiO2 and Al2O3 with trace element inclusions of Hg, Ti, Cd and As. The soil, sediment and overburden in the coal mining areas contain pyrite as Fe-S-mineral and also ferrous sulphate as weathering product, with illite the main clay mineral. From laboratory leaching products of coal and ash, sulphur in the form of SO\(_{4}^{2-}\), was found to be one of the most leached ions with a concentration ranging between 100–1000 ppm. The amount of Fe leached out from the ash samples was between 2–5 ppm, but the Fe-leachability depends on the pH, with higher amounts leached out at pH ≤ 1.5. Magnetite losses, to the amount of about 1kg per tonne of magnetite used, occur during the dense medium separation process (DMS) used in cleaning the coal, which also reports in the waste product. South Africa is the largest producer of platinum and smelting of the ore can lead to various forms of pollution. Magnetite formation in the 2-stage furnace process is used as an indicator of the effectiveness of the reduction and the Fe2+ and Fe3+ ratio is used to monitor the process. In the flash furnace the ratio is 2–6, whilst in the electric furnace it is ≤0.02. If not monitored closely a large amount of nickel loss will occur if sent to the waste dump. Mössbauer spectroscopy was used to identify the Fe-species and the results were augmented by High Resolution-Transmission Electron microscopy (HR-TEM), Field Emission-Scanning Electron Microscopy (FE-SEM)/EDS, X-Ray Diffraction (XRD) and ICP-EOS results.
Similar content being viewed by others
References
http://www.southafrica.info/business/economy/sectors/mining.htm, accessed on 3 July 2016
Hall, I.: Overview of the South African Coal Value Chain, South African National Energy Development Institute–SANEDI (www.sanedi.org.za). p 231 (2011)
http://www.theodora.com/wfbcurrent/india/india_economy.html, accessed 1 September 2016
www.tradingeconomics.com/brazil/gdp-from-mining, accessed on 3 September 2016
Waanders, F.B.: The use of Mössbauer spectroscopy in coal research: Is it relevant or not? In: Sharma, V.K., Klingelhofer, G., Nishida, T (eds.) Mössbauer Spectroscopy: Applications in Chemistry, Biology, and Nanotechnology, 1st edn. chap 30, pp 576–501. Wiley, New York (2013)
Silva, L.F.O., Macias, F., Oliveira, M.L.S., da Boit, K.M., Waanders, F.: Coal cleaning residues and Fe-minerals implications. Environ. Monit. Assess. 172 (1–4), 367–378 (2011)
Hower, J.C., Graham, U.M., Wong, A.S., Robertson, J.D., Haeberlin, B.O., Thomas, G.A., Schram, W.H.: Influence of flue-gas desulfurization systems on coal combustion by-product quality at Kentucky power stations burning high-sulfur coal. Waste Manag. 17(8), 523–33 (1998)
Tiwary, R.K.: Environmental impact of coal mining on water regime and its management. Water Air Soil Pollut. 132(1–2), 185–199 (2000)
Ntwampe, I.O., Waanders, F.B., Fosso-Kankeu, E, Bunt, J.R.: Turbidity removal efficiency of clay and a synthetic af-PFCl polymer of magnesium hydroxide in AMD treatment. Int. Sci. Res. J. 06, 38–55 (2015). doi:10.18483/IRJSci.74
Mielke, R.E., Pace, D.L., Porter, T., Southam, G.: A critical stage in the formation of acid mine drainage: colonization of pyrite by Acidithiobacillus ferrooxidans under pH-neutral conditions. Geobiology 1, 81–90 (2003). doi:10.1046/j.1472-4669.2003.00005.x
Duan, J., Gregory, J.: Coagulation by hydrolysing metal salts. Adv. Colloid Interf. 100–102, 475–502 (2003)
McCarthy, T., Rubidge, B.: The story of earth & life: a southern African perspective on a 4.6-billion-year journey, 326p. Struik Publishers, Cape Town (2005)
Woollacott, L.C., Eric, R.H.: Mineral and Metal Extraction An Overview, 331p. The South African Institute of Mining and Metallurgy, Johannesburg (1994)
Andrews, L., Pistorius, P.C., Waanders, F.B.: Electron beam and Mössbauer techniques combined to optimise base metal partitioning in the furnace. Michrochim. Acta 161, 445–450 (2008)
Waanders, F.B., Nell, J.: Phase chemical composition of slag from a direct nickel flash furnace and associated slag cleaning furnace. Hyperfine Interact. 218, 101–105 (2013). doi:10.1007/s10751-012-0699-z
Stevens, J.G., Khasanov, A.M., Miller, J.W., Pollak, H., Li, Z. (eds.): In: Mössbauer Mineral Handbook, Mössbauer Effect Data Centre. University of North Carolina, Asheville, 527p (1998)
Uwaoma, R.C.: Water leaching of inorganic species from coal ash and slag generated at typical Underground Coal Gasification (UCG) temperature, M.Sc. dissertation. North-West University, 204p (2017)
Ward, C.R., French, D., Jankowski, J.: Comparative evaluation of leachability test methods and element mobility for selected Australian fly ash samples. Co-operative Research Centre for Coal in Sustainable Development, 22. http://Pandora.nla.gov.au/pan/64389/20080828-1328/www.ccsd.biz/publications/694.html.22pp (2003)
Kronbauer, M.A., Dai, M.I.S., Waanders, F.B., Wagner, N.J., Mastaler, M., Hower, J.C., Oliveira, M.L.S., Silva, L.F.O.: Geochemistry of ultra-fine and nano-compounds in coal gasification ash. Sci. Total Environ. 456–457, 95–103 (2013)
Silva, L.F.O., DaBoit, K., Sampaio, C.H., Jasper, A., Andrade, M.L., Kostova, I.J., Waanders, F.B., Henke, K.R., Hower, J.C.: The occurrence of hazardous volatile elements and nanoparticles in Bulgarian coal fly ashes and the effect on human health exposure. Sci. Total Environ. 416, 513–526 (2012)
Napier-Munn, T.J., Kojovic, T., Scott, I.A., Shi, F., Masinja, J.H., Baguley, P.J.: Some causes of medium loss in dense medium plants. Miner. Eng. 8 (6), 659–678 (1995)
Waanders, F.B., Mans, A.: Ferrosilicon –DMS medium characterisation and degradation during use, 2003. In: XXIIth IMPC-proceedings, pp. 396–401 (2003)
Waanders, F.B., Smit, D.S.: The leaching of a sulphide ore—a Mössbauer and SEM perspective. Hyperfine Interact. C5, 471–474 (2003)
Author information
Authors and Affiliations
Corresponding author
Additional information
This article is part of the Topical Collection on Proceedings of the 15th Latin American Conference on the Applications of the Mössbauer Effect (LACAME 2016), 13–18 November 2016, Panama City, Panama
Edited by Juan A. Jaén
Rights and permissions
About this article
Cite this article
Waanders, F.B., Silva, L.F.O. & Saikia, B.K. The use of Mössbauer spectroscopy in environmental research. Hyperfine Interact 238, 52 (2017). https://doi.org/10.1007/s10751-017-1423-9
Published:
DOI: https://doi.org/10.1007/s10751-017-1423-9