DBPapers
DOI: 10.5593/SGEM2014/B52/S20.080

REVIEW OF CURRENT TRENDS IN WAYS OF FLY ASH APPLICATION

M. Ondova, A. Sicakova
Wednesday 1 October 2014 by Libadmin2014

References: 14th International Multidisciplinary Scientific GeoConference SGEM 2014, www.sgem.org, SGEM2014 Conference Proceedings, ISBN 978-619-7105-18-6 / ISSN 1314-2704, June 19-25, 2014, Book 5, Vol. 2, 603-610 pp

ABSTRACT
Environment, sustainability, waste free and economic is the concept used in today´s world. The prognosticator stresses the dangers of natural resources exhaustion. In accordance to the criteria of sustainable development, environmentalists emphasize the necessary changes in the consumption of limited natural resources due to ensure the energy saving, and material recycling. Power and heating plants seems to be a worldwide problem in terms of huge amounts of waste production. At the other hand this waste has a great potential to substitute a natural raw sources. Fly ash, a by-product of the coal-burning power industry, is an industrial waste having the great significance to its multifunctional applications. It is defined as a fine grained residue of coal combustion in thermal production stations of electrical energy, which particles are smaller and almost totally spherical in shape, allowing them to fill voids, flow easily, and blend freely in mixtures. The current annual worldwide production of coal ash is estimated about 700 million tons of which 70 % is fly ash at least and based on the more references, fly ash can be used in different areas of building engineering thanks to its appropriate characteristics. It is obvious that the type of combusted coal has the significant impact on the chemical, physical and mineralogical characteristics of the fly ash and its further utilization. The paper presents the current trends of coal fly ash (FA) utilization as a secondary/alternative raw material for building materials production, while the typical portion of fly ash in the unit is quantified. Following the amounts of coal fly ash studies presented worldwide, the aim of this paper is specification of high interested areas. The review then includes its using in materials like: ordinary concretes, high volume fly ash concrete, road concrete, autoclaved aerated concrete, geopolymers, ceramic and fly ash bricks, as well. Based on the analysis it is possible to present the building products containing biggest portions of fly ash, thus it shows the effectiveness for achievement of sustainable development ideas.

Keywords: sustainable development, environment, coal fly ash, building materials