Characterization of MSWI fly ash through mineralogy and water extraction

Athanasius P. Bayuseno and Wolfgang W. Schmahl

Resources, Conservation & Recycling, 2011, vol. 55, issue 5, 524-534

Abstract: This paper investigates the mineralogical characteristics of fresh, aged and hot water extracted MSWI fly ash for providing the baseline information of minerals stability which controls the released heavy metals into the environment. Quantitative determination of bulk phase abundance in the fresh fly ash by the XRD Rietveld refinement method provided composition levels for amorphous and crystalline phases such as potassium tetrachlorozincate (K2ZnCl4), gehlenite, halite, quartz, anhydrite, and feldspar. The minerals association in the fly ash is clearly unstable and subject to mineralogical reactions. The phases of K2ZnCl4, halite and anhydrite in the fresh fly ash were involved in hydration and dissolution/precipitation processes to form new minerals such as the Zn-bearing mineral gordaite, syngenite, gypsum and hydrocalumite. The solubility-controlling phases and extractability of heavy metals were examined in a Soxhlet hot water-extractor. Here the soluble salts were simply removed from fly ash while Ca-, Al-, Si- and SO42−-bearing hydrate minerals were precipitated from the extraction solution. Furthermore, a low release of heavy metals Zn, Pb and Cd in hot water was noticed, indicating a strong retention of the trace metals in the mineral phases remaining in the insoluble fly ash residues.

Keywords: MSWI fly ash; XRD Rietveld method; Mineralogical alteration; Soxhlet water extraction (search for similar items in EconPapers)
Date: 2011
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0921344911000048
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:recore:v:55:y:2011:i:5:p:524-534

DOI: 10.1016/j.resconrec.2011.01.002

Access Statistics for this article

Resources, Conservation & Recycling is currently edited by Ming Xu

More articles in Resources, Conservation & Recycling from Elsevier
Bibliographic data for series maintained by Kai Meng ().