Grate fly ash and fluidized bed fly ash mixed with glass cullet additive respectively were melted in the electronic arc-furnace. The product, arc-melting slag, was further treated by crushing, pressing and heat treatm...Grate fly ash and fluidized bed fly ash mixed with glass cullet additive respectively were melted in the electronic arc-furnace. The product, arc-melting slag, was further treated by crushing, pressing and heat treatment in order to make the glass-ceramics. The crystallization behaviors of the produced glass-ceramics were examined by differential thermal analysis (DTA), X-ray diffractometry (XRD) and scanning electron microscopy (SEM). Results show that main crystalline phase of the glass-ceramics fi'om grate fly ash is wollastonite (CaSiO3) with small amount of diopside (Ca(Mg,Al)(Si,Al)206), and that from fluidized bed fly ash is diopside (Ca(Mg,Al)(Si,Al)206). It is found that the glass-ceramics sintered at 850 ℃and 1 000℃ from grate fly ash and fluidized bed fly ash respectively have the optimal physical, mechanical and chemical characteristics. Glass-ceramics samples, produced from incinerator fly ash with desirable properties and the low leaching concentration of heavy metals, can be the substitute of nature materials such as marble, granite and porcelain tiles.展开更多
Waste cathode ray tube(CRT)funnel glass(FG)is an important part in the disposal of electrical and electronic waste(e-waste).A novel approach for efficient lead extraction and glass-ceramics synthesized from waste FG t...Waste cathode ray tube(CRT)funnel glass(FG)is an important part in the disposal of electrical and electronic waste(e-waste).A novel approach for efficient lead extraction and glass-ceramics synthesized from waste FG through collaboratively smelting FG with coal fly ash(CFA)is proposed.Glass-ceramics materials with 40 wt%-80 wt%FG additions were produced under sintering temperatures of 900-1000℃.The microstructure and phase composition of the produced glass-ceramics were studied using X-ray diffraction(XRD)and scanning electron microscopy(SEM).The density,water absorption,Vicker hardness,chemical resistance and heavy metal leaching characteristics of the glassceramics were measured.The experimental results indicate that the samples can be crystallized at sintering temperatures of 900-1000℃.An elevated sintering temperature is favorable for enhancing the degree of crystallization,while the crystallization process is inhibited at excessively high temperatures.Increasing FG addition can lead to the transformation of the main crystalline phase from diopside to gehlenite.Well-crystallized crystals were generated in the specimens with 50 wt%-70 wt%FG additions.The samples with 40 wt%,50 wt%,60 wt%,70 wt%,80 wt%FG addition exhibit the optimal chemical and physical properties at 975,925,950,925 and 900℃,respectively.Overall results demonstrate that this study provides a feasible strategy for reliably detoxifying and reusing waste FG and CFA.展开更多
基金Project(20806051) supported by the National Natural Science Foundation of ChinaProject(20080440680) supported by China Postdoctoral Science Foundation
文摘Grate fly ash and fluidized bed fly ash mixed with glass cullet additive respectively were melted in the electronic arc-furnace. The product, arc-melting slag, was further treated by crushing, pressing and heat treatment in order to make the glass-ceramics. The crystallization behaviors of the produced glass-ceramics were examined by differential thermal analysis (DTA), X-ray diffractometry (XRD) and scanning electron microscopy (SEM). Results show that main crystalline phase of the glass-ceramics fi'om grate fly ash is wollastonite (CaSiO3) with small amount of diopside (Ca(Mg,Al)(Si,Al)206), and that from fluidized bed fly ash is diopside (Ca(Mg,Al)(Si,Al)206). It is found that the glass-ceramics sintered at 850 ℃and 1 000℃ from grate fly ash and fluidized bed fly ash respectively have the optimal physical, mechanical and chemical characteristics. Glass-ceramics samples, produced from incinerator fly ash with desirable properties and the low leaching concentration of heavy metals, can be the substitute of nature materials such as marble, granite and porcelain tiles.
基金Project(2020GDASYL-20200103101)supported by the GDAS’Project of Science and Technology Development,ChinaProject(2020A1515010729)supported by the Natural Science Foundation of Guangdong Province,ChinaProject(2018YFC1902004)supported by the National Key R&D Program of China。
文摘Waste cathode ray tube(CRT)funnel glass(FG)is an important part in the disposal of electrical and electronic waste(e-waste).A novel approach for efficient lead extraction and glass-ceramics synthesized from waste FG through collaboratively smelting FG with coal fly ash(CFA)is proposed.Glass-ceramics materials with 40 wt%-80 wt%FG additions were produced under sintering temperatures of 900-1000℃.The microstructure and phase composition of the produced glass-ceramics were studied using X-ray diffraction(XRD)and scanning electron microscopy(SEM).The density,water absorption,Vicker hardness,chemical resistance and heavy metal leaching characteristics of the glassceramics were measured.The experimental results indicate that the samples can be crystallized at sintering temperatures of 900-1000℃.An elevated sintering temperature is favorable for enhancing the degree of crystallization,while the crystallization process is inhibited at excessively high temperatures.Increasing FG addition can lead to the transformation of the main crystalline phase from diopside to gehlenite.Well-crystallized crystals were generated in the specimens with 50 wt%-70 wt%FG additions.The samples with 40 wt%,50 wt%,60 wt%,70 wt%,80 wt%FG addition exhibit the optimal chemical and physical properties at 975,925,950,925 and 900℃,respectively.Overall results demonstrate that this study provides a feasible strategy for reliably detoxifying and reusing waste FG and CFA.