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HEAVY AND TOXIC ELEMENTS DISTRIBUTION IN MAGNETICALLY SEPARATED FRACTIONS FROM COAL FLY ASHES

A. Shoumkova, V. Stoyanova

First published: 2010DOI pendingView metrics

Abstract

The analytical results for the concentration of about 50 elements in magnetic fractions, obtained by wet low intensity magnetic separation of fly ashes from six coal burning power plants in Bulgaria, have been compared to the data previously reported [1] for the initial fly ashes. It has been found that the total content of heavy and toxic elements in magnetic fractions is lower than that in the source materials. The concentrations of Cr, Mn, Co, Ni, and, in some ashes, of V and Cu are almost proportional to the content of Fe in magnetic fractions, indicating their presence in substituted magnetite or maghemite. In some magnetic fractions a slight enrichment of Ce, Hf, Zn, etc. has been also observed, but most of the trace elements (As, Pb, Pr, Rb, Sc, Sr, Sn, Tl, Zr, etc.) are concentrated in non-magnetic fractions. The chemical compositions of about 900 single particles, selected by brightness criterion in backscattering electrons mode, have been determined by means of SEM-EDX. It has been confirmed that many heavy metals and other toxic trace elements (Ba, Sr, Pb, Tl, Cd, etc.) exist predominantly in separate particles - alone, in typical combinations, or accompanied by Al and Si. The statistic data for the association of trace elements with iron and aluminosilicate matter, generally confirm the conclusions made on the base of the bulk analyses.

Publication details

Title
HEAVY AND TOXIC ELEMENTS DISTRIBUTION IN MAGNETICALLY SEPARATED FRACTIONS FROM COAL FLY ASHES
Authors
A. Shoumkova, V. Stoyanova
Proceedings
10th International Multidisciplinary Scientific GeoConference SGEM2010
Publisher
SGEM Scientific GeoConference
Year
2010
Pages
597-604
SWS Citekey
Shoumkova2010291
ISSN
Not available yet
ISBN
954-91818-1-2
Language
en
Publication type
Conference Paper
Keywords
Coal fly ashSEM-EDXmagnetic fractiontrace elements
References28

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