Methodology for analysis of the reactivity of coal fly ash using selective dissolution by hydrofluoric acid
| Autor: | Elisabete Teixeira, Rui L. Reis, Manuel Joaquim Peixoto Marques Ribeiro, Aires Camões, Rui Reis, Raphaele Malheiro, João Abrantes |
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| Přispěvatelé: | Universidade do Minho |
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
Chemical and physical analysis
Materials science 020209 energy XRF 02 engineering and technology Fly ash Energy dispersive spectroscopy Clinker (cement) vitreous phase EDS acid attack chemistry.chemical_compound Hydrofluoric acid Engenharia e Tecnologia::Engenharia Civil Phase (matter) 0202 electrical engineering electronic engineering information engineering Concretes General Materials Science Reactivity (chemistry) Thermoelectric power plants Acid attack Chemical analysis Selective dissolution method Dissolution Cement Reactive potentials Rietveld refinement Mechanical Engineering Metallurgy fungi Vitreous phase Crystalline materials Selective dissolution Coal ash Cement replacement chemistry Mechanics of Materials selective dissolution SEM Scanning electron microscopy Crystalline phasis |
| Zdroj: | Repositório Científico de Acesso Aberto de Portugal Repositório Científico de Acesso Aberto de Portugal (RCAAP) instacron:RCAAP |
| Popis: | The use of some additions as cement replacement has played an important role in the amount of clinker reduction. Due to its huge worldwide availability one of the most important and recognised replace agent is the fly ash, but is also estimated that only 30 to 40% of fly ash is used, although there are some challenges to be overcome, such as the reactive potential quantification. Chemical analysis is typically determined by the oxides content and does not take into account the vitreous and crystalline phase ratio. Therefore, this paper describes in detail one selective dissolution method, based in the hydrofluoric acid attack, to the quantification of the vitreous phase (reactive) and crystalline phases (not reactive). Fly ash from Portuguese Pego thermoelectric power plant was submitted to different attacks. To confirm the method and its effects, chemical and physical analysis were performed, such as STA, XRF, XRD with Rietveld refinement, SEM, EDS and laser diffraction granulometry. The results can be used to quantify the potential reactivity of this type of fly ash. The best results were achieved with 1% hydrofluoric acid attack during 6 hours. The authors wish to acknowledge the SEM and XRD facilities were funded by FEDER Funds through QREN – Aviso SAIECT-IEC/2/2010, Operação NORTE-07-0162-FEDER-000050. |
| Databáze: | OpenAIRE |
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