TRACE ELEMENTS IN FLY ASHES FROM “VARNA”, “BOBOV DOL”, “MARITZA IZTOK I”, “MARITZA ІІІ”, „REPUBLIKA” AND “ROUSSE IZTOK” POWER PLANTS, BULGARIA

6th International Scientific Conference - SGEM2006, www.sgem.org, SGEM2006 Conference Proceedings/ ISBN: 954-918181-2, June 12-16, 2006, Vol. 1, 349-358 pp

ABSTRACT

A comparative study of the content of five macro- and about fifty micro- and trace elements in fly ashes from six coal-burning power plants in Bulgaria is carried out by means of a combination of Chemical Analysis, AAS, X-Ray Luminescence and X-Ray Fluorescence EDA. The elements’ distribution among and within single particles is investigated on the base of the comparison of data from bulk analysis, micro-analysis, and the results from acid leaching tests using 0.1M HNO3. It is established that many heavy metals and other toxic trace elements (Ba, Cu, Sr, Pb, Tl, Cd, some Lanthanides and rare elements) exist predominantly in singe particles and/or acid-soluble forms and up to 70% of them could be extracted, when just 3÷15% of aluminosilicate material is dissolved. The results are discussed from chemical and ecological point of view.

Keywords: coal fly ash, trace elements, acid leaching, EPXMA.