Strength, leachability and microstructure characterisation of Na2SiO3-activated ground granulated blast-furnace slag solidified MSWI fly ash.
The chemical composition and the leachability of heavy metals in municipal solid waste incinerator (MSWI) fly ash were measured and analysed. For the leachability of unstabilized MSWI fly ash it was found that the concentrations of Pb and Cr exceeded the leaching toxicity standard. Cementitious solidification of the MSWI fly ash by Na2SiO3-activated ground granulated blast-furnace slag (NS) was investigated. Results show that all solidified MSWI fly ash can meet the landfill standards after 28 days of curing. The heavy metals were immobilized within the hydration products such as C-S-H gel and ettringite through physical encapsulation, substitution, precipitation or adsorption mechanisms.
Zhang
Dajie
D
College of Resource and Environment, Wuhan University, NO. 129 Luoyu Road, Wuhan 430079, PR China. zdajie1015@hotmail.com
Liu
Wenshi
W
Hou
Haobo
H
He
Xinghua
X
D002244:Carbon / Q000032:analysis* / Q000737:chemistry; D060729:Coal Ash; D019245:Compressive Strength; D017745:Incineration; D007220:Industrial Waste; D019216:Metals, Heavy / Q000032:analysis; D008855:Microscopy, Electron, Scanning; D052638:Particulate Matter / Q000032:analysis* / Q000737:chemistry; D017640:Silicates / Q000737:chemistry; D018505:Waste Management / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis
D060729:Coal Ash; D007220:Industrial Waste; D019216:Metals, Heavy; D052638:Particulate Matter; D017640:Silicates; D014874:Water Pollutants, Chemical; D002244:Carbon; C005691:sodium silicate