Journal
INTERNATIONAL JOURNAL OF COAL GEOLOGY
Volume 116, Issue -, Pages 75-92Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.coal.2013.07.002
Keywords
Mineral matter; X-ray diffraction; Coal preparation; Pyrite; Trace element
Categories
Funding
- National Council of Technological and Scientific Development (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq)
- CNPq
- Fundacao de Amparo a Pesquisa do Estado do Rio Grande do Sul (FAPERGS)
- Centro Universitario Lasalle-Canoas (UNILASALLE)
Ask authors/readers for more resources
Comparative studies of the mineral matter and trace elements in 12 pairs of run-of-mine (ROM) and clean-coal products from beneficiation plants in Santa Catarina, southern Brazil, have been carried out using low-temperature oxygen-plasma ashing, X-ray diffraction and chemical analysis techniques with the aim of evaluating the effect of coal preparation on the mineralogy and chemical composition of the final coal products. The results show that substantial reductions in mineral matter and ash percentages are associated with beneficiation of coals mined from the different deposits. These reductions are accompanied by changes in the percentages of Fe2O3 in the respective coal ashes, due to the reduction in the proportion of pyrite in the mineral matter, and also by a reduction in the percentage of Na2O, possibly due to ion exchange within the clay minerals. The relative proportions of quartz, clay minerals, and minor phases such as calcite and feldspar (mainly albite) within the mineral matter are not, however, significantly changed by the beneficiation processes. The concentrations of most trace elements in the beneficiation products are similar to the respective concentrations in the relevant ROM materials, or are reduced to an extent similar to that of the total mineral matter percentage for the respective coal samples. This suggests an association mainly with the clay-rich mineral matter. The concentrations of As and Pb, however, are reduced to a greater extent for most samples by the beneficiation processes, consistent with a pyrite association. Concentrations of Ge, U and Zr are higher in many of the clean coals than in the respective run-of-mine materials, suggesting the possibility of preferential association, at least for some deposits, with the organic-rich fractions of the coals concerned. (C) 2013 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available