摘要
Heavy metal containing pickling sludge(PS) is one of the by-products of the stainless-steel-making industry,which has been considered hazardous due to contained chromium and nickel.Traditional methods of PS disposing are landfill and cement solidification.This research is aimed at disposing PS by solidification/stabilization and reusing it as a nucleation agent of glass–ceramics.The crystallization behavior and the properties of a glass in the CaO–MgO–SiO2–Al2O3 system were studied by considering PS as the nucleation agent.Experimental results confirm that introducing 14 wt% PS as the nucleation agent of glass–ceramics can decrease crystallization temperature by 110.8 °C,refine the grain size by forming isometric crystals with size of 2 lm,enhance Vickers hardness by 2690 MPa and decrease water absorption from(1.21 ± 0.10) wt% to(0.04 ± 0.01) wt%.Therefore,it is reasonable to conclude that PS can be utilized as a nucleation agent to improve the crystallization and mechanical properties of the glass–ceramics.The testing results of US EPA toxicity characteristic leaching procedure(TCLP)confirm the safety of this reusing method.
Heavy metal containing pickling sludge(PS) is one of the by-products of the stainless-steel-making industry,which has been considered hazardous due to contained chromium and nickel.Traditional methods of PS disposing are landfill and cement solidification.This research is aimed at disposing PS by solidification/stabilization and reusing it as a nucleation agent of glass–ceramics.The crystallization behavior and the properties of a glass in the CaO–MgO–SiO2–Al2O3 system were studied by considering PS as the nucleation agent.Experimental results confirm that introducing 14 wt% PS as the nucleation agent of glass–ceramics can decrease crystallization temperature by 110.8 °C,refine the grain size by forming isometric crystals with size of 2 lm,enhance Vickers hardness by 2690 MPa and decrease water absorption from(1.21 ± 0.10) wt% to(0.04 ± 0.01) wt%.Therefore,it is reasonable to conclude that PS can be utilized as a nucleation agent to improve the crystallization and mechanical properties of the glass–ceramics.The testing results of US EPA toxicity characteristic leaching procedure(TCLP)confirm the safety of this reusing method.
基金
financially supported by the National Natural Science Foundation of China (Nos.51502014,51472030 and U1360202)
the National Key Project of the Scientific and Technical Support Program of China (No.2012BAC02B01)
the National Hi-Tech R&D Program of China (No.2012AA063202)
the Fundamental Research Funds for the Central Universities (No.FRF-TP-15-050A2)
the China Postdoctoral Science Foundation Funded Project (No.2014M560885)