Ageing of ashes in a landfill top cover
2011 (English)In: SARDINIA 2011: Thirteenth International Waste Management and Landfill Symposium, S. Margherita di Pula, Cagliari, Italy; 3 - 7 October 2011 / [ed] Raffaello Cossu, Cagliari: CISA Publisher, Italy , 2011Conference paper (Refereed)
This paper is based on studies on the effects of accelerated ageing on refuse-derived-fuel (RDF) fly ashes, in experiments under controlled laboratory conditions, intended to derive models to predict the stability of RDF fly ashes used in a landfill liner and the mineralogi-cal changes that occur in them. A reduced factorial design was applied, followed by multivariate data analysis, to evaluate the effects of five factors — carbon dioxide (CO2) levels, temperature, relative air humidity (RH), time and the quality of added water — on mineral transformations within the ashes, and leaching behaviour. The pH values of these ash specimens ranged from 7.2 to 7.6, indicating advanced carbonation. Ageing decreased pH values from 12.4 to 7.2, conse-quently affecting the leaching behaviour of most chemicals measured in the leachates. Levels of Ba, Ca, Cl, Cr, Cu, Pb, K and Na decreased over the study period while those of Mg, Zn and SO4 increased. Clay minerals could not be detected neither in fresh nor in aged ashes. However, geo-chemical modelling indicated that such minerals may precipitate.
Place, publisher, year, edition, pages
Cagliari: CISA Publisher, Italy , 2011.
Research subject Waste Science and Technology
IdentifiersURN: urn:nbn:se:ltu:diva-27914Local ID: 17fedbbc-0fee-4451-ba41-57b465cdda0aOAI: oai:DiVA.org:ltu-27914DiVA: diva2:1001105
International Waste Management and Landfill Symposium : 03/10/2011 - 07/10/2011
Godkänd; 2011; 20111107 (evebra)2016-09-302016-09-30Bibliographically approved