Energy Research, Vol. 3, Issue 2, Jun  2019, Pages 13-23; DOI: 10.31058/ 10.31058/

Evaluation of Fluidized Bed Ashes from Animal Wastes, Properties, Environmental Impact and Valorization

, Vol. 3, Issue 2, Jun  2019, Pages 13-23.

DOI: 10.31058/

Despina Vamvuka 1* , Despina Pentari 1

1 Department of Mineral Resources Engineering, Technical University of Crete, Chania, Greece

Received: 19 April 2019; Accepted: 20 May 2019; Published: 10 June 2019

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Use of secondary fuels for power production, such as animal and agricultural wastes, is becoming important nowadays, in view of the declining reserves of fossil fuels. Fluidized bed furnaces offer many advantages, such as fuel flexibility, high efficiency and low pollutant emissions. However, bottom or fly ashes produced from these appliances may create technical and environmental problems. In this study, agricultural wastes from the island of Crete (S. Europe) were co-fired in a fluid bed unit and bottom and fly ashes were characterized by mineralogical and chemical analyses. The effect of ash materials on system’s performance, as well as their environmental impact and valorization were assessed. The results showed that all ashes were enriched in Ca, Si, Mg, P, K. These elements were principally associated with calcite, anhydrite, quartz, dolomite, hydroxyapatite, fairchildite and arcanite minerals. Animal waste ashes contained whitlockite, calcium sodium phosphate and epsonite. Combustion of animal manure above 1000°C could lead to deposition problems in furnaces. Heavy metals Cu, Zn, Mn and Sr dominated in fly ashes. Toxic elements leached through alkaline soil of phyllitic and quarzitic natures were below legislation limits for land disposal. All ashes could be used for soil amelioration, liming or possibly fertilization.


Agricultural Wastes, Animal Wastes, Fluidized Bed, Ash Leaching


© 2017 by the authors. Licensee International Technology and Science Press Limited. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


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