Effect of Particle Size on the Speciation Distribution of Heavy Metals in MSWI Fly Ash

2011 ◽  
Author(s):  
Yanlong Li ◽  
Rundong Li ◽  
Zhihui Zhang ◽  
Haijun Zhang ◽  
Lei Wang ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Particle Size ◽  
Fly Ash ◽  
Mswi Fly Ash ◽  
Effect Of Particle Size

MSWI fly ash particle size chemical and mineralogical characterization, before and after leaching tests, aimed to reuse. 

2021 ◽  
Author(s):  
Enrico Destefanis ◽  
Caterina Caviglia ◽  
Angelo Agostino ◽  
Davide Bernasconi ◽  
Linda Pastero ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Particle Size ◽  
Fly Ash ◽  
Waste Incinerator ◽  
X Ray Diffraction ◽  
Mswi Fly Ash ◽  
Mineralogical Characterization ◽  
X Ray ◽  
Ms Analysis ◽  
Icp Ms

<p>Municipal solid waste incinerator (MSWI) fly ash can represent a sustainable source of construction materials, but it needs to be treated in order to remove dangerous substances as chlorides, sulfates, and heavy metals. The concentration of salts and heavy metals in fly ash usually exceeds the law threshold and so they are considered a hazardous waste, unsuitable for reuse in concrete and civil engineering applications.In this work, a complete characterization of fly ash coming from a northern Italy thermovalorization plant was investigated, both on the solid and leachates composition, focused on the particle size, by X-Ray fluorescence and X-Ray diffraction on the solid matrices and ICP-MS analysis on the leachates.Using mechanical sieving on several subsamples of fly ash, six different particle size were separated and analyzed, and compared to the bulk fly ash composition.The most abundant elements are represented by Ca, Cl, S, and Si; trace elements and heavy metals are mainly represented by Zn, Fe, Al, Pb. The XRF and ICP-MS analysis show a general increasing trend, as the particle size decrease, of Na, K, Cl, S, as well as Cr, Cd, Cu, Pb, Sb, Zn, Ba, both on solid and leachates composition; on the contrary Ca and Si decrease.After leaching Cl and K decrease consistently, while it can be observed an increase of all the other elements, due to the weight loss attributable mainly to the leaching of Na-K chlorides, that is confirmed also by the X-Ray diffraction analysis.</p>

The Particle Size Distribution, Gross Contents of Heavy Metals and its Leaching Behavior of Fly Ash from Municipal Solid Wastes Incineration of Chongqing

2011 ◽  
Vol 414 ◽  
pp. 166-171 ◽  
Author(s):  
Si Chen Liu ◽  
Chang Sheng Jiang ◽  
Qing Ju Hao ◽  
Qing Ling Li ◽  
Yan Shi
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Particle Size ◽  
Fly Ash ◽  
Waste Incinerator ◽  
Particle Sizes ◽  
Municipal Solid Wastes ◽  
Mswi Fly Ash ◽  
Heavy Metal Leaching ◽  
Leaching Procedure

The distributions in different particle sizes of municipal solid waste incinerator (MSWI) fly ash in spring and autumn were studied by sieve method, and the heavy metal contents of Cu, Zn, Mn, Pb, Cd, Ni, Cr and Hg in different size particles were measured, and the heavy metal leaching amount in the different particle size were also studied under the GB5085.3-2007 and USEPA-TCLP leaching procedure, respectively. The results showed that the particle size of fly ash in autumn was relatively smaller than that of in spring, more than 90% of particle size of fly ash in spring and autumn were less than 250 μm, and the particle size in 83-105 μm of fly ash in spring distributes in most with about 40% of the total, but 105-149 μm in autumn distributes in most, accounted for about 45% of the total. The content of heavy metals decreased first and then increased with the decreasing particle sizes except for Ni, and the content of heavy metals in the spring is higher than that of in autumn except for Fe and Zn. Under the GB5085.3-2007 leaching procedure, the leaching content of Cu, Zn and Ni in MSWI fly ash in both spring and autumn and Cr in spring were not beyond limited standard, but Pb and Cd in both spring and autumn and Cr in autumn were beyond limited standard. However, under TCLP leaching procedure, the leaching content of Pb, Cr and Cd in both spring and autumn were beyond the standard limits.

scholarly journals An Experimental Study on the Melting Solidification of Municipal Solid Waste Incineration Fly Ash

2021 ◽  
Vol 13 (2) ◽  
pp. 535
Author(s):  
Jing Gao ◽  
Tao Wang ◽  
Jie Zhao ◽  
Xiaoying Hu ◽  
Changqing Dong
Keyword(s):  
Heavy Metals ◽  
High Temperature ◽  
Fly Ash ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Liquid Slag ◽  
Melting Process ◽  
Waste Incineration ◽  
Municipal Solid Waste Incineration ◽  
Mswi Fly Ash

Melting solidification experiments of municipal solid waste incineration (MSWI) fly ash were carried out in a high-temperature tube furnace device. An ash fusion temperature (AFT) test, atomic absorption spectroscopy (AAS), scanning electron microscope (SEM), and X-ray diffraction (XRD) were applied in order to gain insight into the ash fusibility, the transformation during the melting process, and the leaching behavior of heavy metals in slag. The results showed that oxide minerals transformed into gehlenite as temperature increased. When the temperature increased to 1300 °C, 89 °C higher than the flow temperature (FT), all of the crystals transformed into molten slag. When the heating temperatures were higher than the FT, the volatilization of the Pb, Cd, Zn, and Cu decreased, which may have been influenced by the formation of liquid slag. In addition, the formation of liquid slag at a high temperature also improved the stability of heavy metals in heated slag.

Influence of speciation distribution and particle size on heavy metal leaching from MSWI fly ash

2022 ◽  
Vol 138 ◽  
pp. 318-327
Author(s):  
Davide Bernasconi ◽  
Caterina Caviglia ◽  
Enrico Destefanis ◽  
Angelo Agostino ◽  
Renato Boero ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Particle Size ◽  
Fly Ash ◽  
Metal Leaching ◽  
Mswi Fly Ash ◽  
Heavy Metal Leaching

scholarly journals Inventory of MSWI Fly Ash in Switzerland: Heavy Metal Recovery Potential and Their Properties for Acid Leaching

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1668
Author(s):  
Wolfgang Zucha ◽  
Gisela Weibel ◽  
Mirjam Wolffers ◽  
Urs Eggenberger
Keyword(s):  
Heavy Metals ◽  
Fly Ash ◽  
Acid Leaching ◽  
Acid Neutralizing Capacity ◽  
Mswi Fly Ash ◽  
Mineralogical Characterization ◽  
Recovery Rates ◽  
Leaching Potential ◽  
Geochemical Properties ◽  
Neutralizing Capacity

From the year 2021 on, heavy metals from Swiss municipal solid waste incineration (MSWI) fly ash (FA) must be recovered before landfilling. This is predominantly performed by acid leaching. As a basis for the development of defined recovery rates and for the implementation of the recovery process, the authorities and plant operators need information on the geochemical properties of FA. This study provides extended chemical and mineralogical characterization of all FA produced in 29 MSWI plants in Switzerland. Acid neutralizing capacity (ANC) and metallic aluminum (Al0) were additionally analyzed to estimate the effort for acid leaching. Results show that all FA samples are composed of similar constituents, but their content varies due to differences in waste input and incineration conditions. Based on their geochemical properties, the ashes could be divided into four types describing the leachability: very good (6 FA), good (10 FA), moderate (5 FA), and poor leaching potential (8 FA). Due to the large differences it is suggested that the required recovery rates are adjusted to the leaching potential. The quantity of heavy metals recoverable by acid leaching was estimated to be 2420 t/y Zn, 530 t/y Pb, 66 t/y Cu and 22 t/y Cd.

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