TY - JOUR
T1 - Designing low-carbon cement-free binders for stabilization/solidification of MSWI fly ash
AU - Sun, Chen
AU - Ge, Weizhe
AU - Zhang, Yuying
AU - Wang, Lei
AU - Xia, Yan
AU - Lin, Xiaoqing
AU - Huang, Qunxing
AU - Lu, Shengyong
AU - Tsang, Daniel C.W.
AU - Yan, Jianhua
N1 - Funding Information:
The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China (No. 52206174 ) and the Open Project of State Key Laboratory of Clean Energy Utilization , Zhejiang University ( ZJUCEU2022001 ) for this study.
Publisher Copyright:
© 2023 Elsevier Ltd
PY - 2023/8/1
Y1 - 2023/8/1
N2 - Low-carbon and high-efficiency binder is desirable for sustainable treatment of municipal solid waste incineration fly ash (MSWI FA). In this study, CaO or MgO was used to activate ground granulated blast furnace slag (GGBS) to form calcium silicate hydrate and magnesium silica hydrate gel for stabilization/solidification of hazardous MSWI FA. Experimental results showed that potential toxic elements (PTEs), such as Pb and Zn, significantly inhibited the formation of reaction products in CaO-GGBS system due to the complexation between Ca(OH)2 and PTEs, whereas PTEs only had insignificant inhibition on transformation from MgO to Mg(OH)2 in MgO-GGBS system, resulting in lower leachabilities of PTEs and higher mechanical strengths. Stabilization/solidification experiments demonstrated that MSWI FA (70 wt%) could be recycled by MgO-GGBS binder (30 wt%) into blocks with desirable 28-day compressive strengths (3.9 MPa) and PTEs immobilization efficiencies (99.8% for Zn and 99.7% for Pb). This work provides mechanistic insights on the immobilization mechanisms of PTEs in CaO/MgO-GGBS systems and suggests a promising MgO-GGBS binder for low-carbon treatment of MSWI FA.
AB - Low-carbon and high-efficiency binder is desirable for sustainable treatment of municipal solid waste incineration fly ash (MSWI FA). In this study, CaO or MgO was used to activate ground granulated blast furnace slag (GGBS) to form calcium silicate hydrate and magnesium silica hydrate gel for stabilization/solidification of hazardous MSWI FA. Experimental results showed that potential toxic elements (PTEs), such as Pb and Zn, significantly inhibited the formation of reaction products in CaO-GGBS system due to the complexation between Ca(OH)2 and PTEs, whereas PTEs only had insignificant inhibition on transformation from MgO to Mg(OH)2 in MgO-GGBS system, resulting in lower leachabilities of PTEs and higher mechanical strengths. Stabilization/solidification experiments demonstrated that MSWI FA (70 wt%) could be recycled by MgO-GGBS binder (30 wt%) into blocks with desirable 28-day compressive strengths (3.9 MPa) and PTEs immobilization efficiencies (99.8% for Zn and 99.7% for Pb). This work provides mechanistic insights on the immobilization mechanisms of PTEs in CaO/MgO-GGBS systems and suggests a promising MgO-GGBS binder for low-carbon treatment of MSWI FA.
KW - Hazardous waste treatment
KW - Low-carbon stabilization/solidification
KW - PTEs leachability
KW - Sustainable waste management
KW - Waste incineration fly ash
UR - https://www.scopus.com/pages/publications/85152658999
U2 - 10.1016/j.jenvman.2023.117938
DO - 10.1016/j.jenvman.2023.117938
M3 - Journal article
C2 - 37080097
AN - SCOPUS:85152658999
SN - 0301-4797
VL - 339
JO - Journal of Environmental Management
JF - Journal of Environmental Management
M1 - 117938
ER -
