Abstract
In the northern Adriatic coast of Croatia, combustion of super-high organic sulphur rich Raša coal was common between 1970 and 2000. These Late Paleocene coals are enriched in a number of trace elements. This work aims to provide a detailed study on the distinctive geochemical patterns of the Raša coal and investigate the environmental effects of the coal and combustion by-products on the area. Several analytical techniques were used to study the mode of occurrence, distribution, levels and solubility of major and trace elements in the Raša coal, fly ash, slag and soils in an area within 10 km from the power station. Due to the sulphur-rich calcareous depositional environment of the Raša coal, the combustion by-products are enriched in S and Ca. Fly ash and slag are enriched in potentially harmful trace elements i.e. Se, Mo, Hg, V and U. Similar enrichment pattern was found for soils suggesting that resuspension and deposition of airborne coal and fly ash particles, transport of gaseous species in the flue gas by dominant winds and/or leaching from ash deposits may have affected the wider environment. Whilst a large number of trace elements were found to be poorly soluble across samples, the leachable concentrations of Se, Cr and Mo in fly ash and slag are noteworthy. Their organic association in coal enhances volatilisation during combustion and then further condensation on ash particles as readily soluble oxyanionic species. Other oxyanionic metalloids such as As or V were insoluble in fly ash and slag, due to precipitation of solubility-limiting Ca-bearing species.
Original language | English |
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Article number | 104472 |
Journal | Applied Geochemistry |
Volume | 114 |
DOIs | |
State | Published - Mar 2020 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2019 Elsevier Ltd
Funding
The authors are grateful to Dr. Milko Jakšić, and Dr. Stjepko Fazinić (Division of Experimental Physics, Ruđer Bošković Institute, Zagreb, Croatia), who kindly provided the Raša coal, FA, and slags collected during the 1980s by Dr. Vladivoj Valković and archived by Dr. Jakšić and Dr. Fazinić. Prof Xavier Querol is thanked for scientific discussion. Financial support for the international collaboration (PS1.35) was provided by the University of Zagreb (Croatia) . We would also like to acknowledge Generalitat de Catalunya ( AGAUR 2015 SGR33 ). The authors are grateful to Dr. Milko Jak?i?, and Dr. Stjepko Fazini? (Division of Experimental Physics, Ru?er Bo?kovi? Institute, Zagreb, Croatia), who kindly provided the Ra?a coal, FA, and slags collected during the 1980s by Dr. Vladivoj Valkovi? and archived by Dr. Jak?i? and Dr. Fazini?. Prof Xavier Querol is thanked for scientific discussion. Financial support for the international collaboration (PS1.35) was provided by the University of Zagreb (Croatia). We would also like to acknowledge Generalitat de Catalunya (AGAUR 2015 SGR33).
Funders | Funder number |
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Division of Experimental Physics | PS1.35 |
Sveučilište u Zagrebu | |
Generalitat de Catalunya | |
Agència de Gestió d'Ajuts Universitaris i de Recerca | 2015 SGR33 |
Keywords
- Fly ash
- Leaching
- SHOS Raša coal
- Slag
- Soil pollution
- Toxic trace elements