TY - JOUR
T1 - Geoenvironmental weathering/deterioration of landfilled MSWI-BA glass
AU - Wei, Yunmei
AU - Saffarzadeh, Amirhomayoun
AU - Shimaoka, Takayuki
AU - Zhao, Chun
AU - Peng, Xuya
AU - Gao, Junmin
N1 - Funding Information:
This work was supported by National Natural Science Foundation of China (grant nos. 51308564 and 21107147 ), The Central University Basic Scientific Research Foundation of Building Division at Chongqing University (grant no. 106112013CDJZR210004 ) and The 111Project (no. B13041).
PY - 2014/8/15
Y1 - 2014/8/15
N2 - Municipal solid waste incineration bottom ash (MSWI-BA) glass serves as a matrix of assorted bottom ash (BA) compounds. Deterioration of the BA glass phases is quite important as they regulate the distribution of a series of toxic elements. This paper studied landfilled MSWI-BA samples from the mineralogical and geochemical viewpoint to understand the deterioration behavior of the BA glass phases as well as mechanisms involved. Bulk analysis by PXRD as well as micro-scale analysis by optical microscopy and SEM/EDX was conducted for such purposes. The results revealed that dissolution of the BA glass phases has resulted in a deterioration layer of 100-102μm thickness after years of disposal. This rapid weathering process is highly relevant to the specific glass characteristics and solution pH. The BA glass phases with more embedded compounds and cracks/fissures tend to be more vulnerable. Moreover, the generally alkaline pH in ash deposit favors a rapid disruption of the glass phase. The weathering products are mainly gel phases (including AlSi gel, CaAlSi gel, FeAlSi gel etc.) with iron oxide/hydroxide as accessory products. Breakdown of the BA glass phases triggers chemical evolution of the embedded compounds. Based on all the findings above, a model is proposed to illustrate a general evolution trend for the landfilled MSWI-BA glass phases.
AB - Municipal solid waste incineration bottom ash (MSWI-BA) glass serves as a matrix of assorted bottom ash (BA) compounds. Deterioration of the BA glass phases is quite important as they regulate the distribution of a series of toxic elements. This paper studied landfilled MSWI-BA samples from the mineralogical and geochemical viewpoint to understand the deterioration behavior of the BA glass phases as well as mechanisms involved. Bulk analysis by PXRD as well as micro-scale analysis by optical microscopy and SEM/EDX was conducted for such purposes. The results revealed that dissolution of the BA glass phases has resulted in a deterioration layer of 100-102μm thickness after years of disposal. This rapid weathering process is highly relevant to the specific glass characteristics and solution pH. The BA glass phases with more embedded compounds and cracks/fissures tend to be more vulnerable. Moreover, the generally alkaline pH in ash deposit favors a rapid disruption of the glass phase. The weathering products are mainly gel phases (including AlSi gel, CaAlSi gel, FeAlSi gel etc.) with iron oxide/hydroxide as accessory products. Breakdown of the BA glass phases triggers chemical evolution of the embedded compounds. Based on all the findings above, a model is proposed to illustrate a general evolution trend for the landfilled MSWI-BA glass phases.
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U2 - 10.1016/j.jhazmat.2014.05.093
DO - 10.1016/j.jhazmat.2014.05.093
M3 - Article
C2 - 25043593
AN - SCOPUS:84904568957
VL - 278
SP - 610
EP - 619
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
SN - 0304-3894
ER -