Experimental Analysis High calcium Fly Ash Geopolymers Solidification/Stablization of Heavy Metals
Guo Xiaolu and Shi Huisheng
DOI:10.3969/j.issn.1674-4764.2013.02.020
Received ,Revised , Accepted , Available online July 01, 2015
Volume ,2013,Pages 124-128
- Abstract
Utilization of high calcium fly ash geopolymer to solidify/stabilize heavy metals was explored. The solidification/stabilization effectiveness of heavy metals was studied using static and dynamic leaching experiments. Additionally, transferring mechanism and long term safety of heavy metals in geopolymer were also investigated. The results show that the leaching concentrations of heavy metals from the solidified/stabilized matrix were far lower than the limit values, and all the solidified/stabilized ratios of heavy metals reached 98% when the geopolymer solidified/stabilized 0.025% Pb(II), 0.025% Cr(VI), and 0.01% Hg(II), respectively. The results Dynamic leaching experiment show that real time leaching concentrations of heavy metals were lower than allowable maximum values, and the accumulated leaching concentrations became stable after 72 h. After dynamic leaching experiment, the radial distributions of heavy metals in geopolymer specimens were similar. Effective diffusion coefficient and dynamic leaching ratios of heavy metals from geopolymer were very low, and this geopolymer has a good long term safety.