Suitable water content plays a decisive role in the granulation of sintering mixtures.Herein,a method was proposed to predict the suitable water content for effective granulation on the basis of Litster's granulat...Suitable water content plays a decisive role in the granulation of sintering mixtures.Herein,a method was proposed to predict the suitable water content for effective granulation on the basis of Litster's granulation model.The granulation effectiveness of a sintering mixture was predicted by the model,with the allowance error of±10%.The effects of the water absorption properties,particle size composition and content of adhesive particles on the suitable water content were studied.The results showed that the allowable error of prediction was within±0.5%compared to the experimentally determined suitable water content.With an increase in adhesive powder content of mixtures with higher water absorption,the suitable water content increased to achieve similar granulation effectiveness.Moreover,as the amount of concentrates increased,the suitable water content first increased and then remained steady.The influence of the water absorption characteristics of the adhesive particles on the suitable water content was less than that of their particle size composition in the mixture.展开更多
The aim of the present study was to investigate the influence of heavy metals on the polymorph transformation of tricalcium silicate.Heavy metal(0.1wt% to 3.0wt%) of Cr,Zn,Cu,Ni and Pb(in oxides form) was added in...The aim of the present study was to investigate the influence of heavy metals on the polymorph transformation of tricalcium silicate.Heavy metal(0.1wt% to 3.0wt%) of Cr,Zn,Cu,Ni and Pb(in oxides form) was added into the raw mixtures and then sintered together three times at 1450 ℃ for 2 h.The f-CaO content of doped C3S was determined by the glycerol-ethanol method,and their polymorph transformation was investigated by means of XRD and FTIR.Thermal analysis(DTA/DTG) was conducted to determine the reaction temperatures and mass losses during the sintering process of raw mixtures.The concentration of heavy metal in C3S after sintering was determined by ICP-AES.The experimental results indicate that heavy metal doping contributes to a higher symmetry of C3S except for Pb.Addition of up to 3.0wt%,Cr will lead to a decomposition of C3S into C2S and CaO;Zn will cause a transformation from T1 to M2 polymorph,and then to R polymorph;Cu and Ni cause a gradual transformation from T1 to T2 and then to M1 and/or M2 polymorph.During the sintering process,all the Pb releases into atmosphere because of evaporation.展开更多
基金supported in part by the National Natural Science Foundation of China under Grant No.51804347.
文摘Suitable water content plays a decisive role in the granulation of sintering mixtures.Herein,a method was proposed to predict the suitable water content for effective granulation on the basis of Litster's granulation model.The granulation effectiveness of a sintering mixture was predicted by the model,with the allowance error of±10%.The effects of the water absorption properties,particle size composition and content of adhesive particles on the suitable water content were studied.The results showed that the allowable error of prediction was within±0.5%compared to the experimentally determined suitable water content.With an increase in adhesive powder content of mixtures with higher water absorption,the suitable water content increased to achieve similar granulation effectiveness.Moreover,as the amount of concentrates increased,the suitable water content first increased and then remained steady.The influence of the water absorption characteristics of the adhesive particles on the suitable water content was less than that of their particle size composition in the mixture.
基金Funded by the National Natural Science Foundation of China(51002110)the Fundamental Research Funds for the Central Universities(2012-IV-025)the State Scholarship Program of China Scholarship Council
文摘The aim of the present study was to investigate the influence of heavy metals on the polymorph transformation of tricalcium silicate.Heavy metal(0.1wt% to 3.0wt%) of Cr,Zn,Cu,Ni and Pb(in oxides form) was added into the raw mixtures and then sintered together three times at 1450 ℃ for 2 h.The f-CaO content of doped C3S was determined by the glycerol-ethanol method,and their polymorph transformation was investigated by means of XRD and FTIR.Thermal analysis(DTA/DTG) was conducted to determine the reaction temperatures and mass losses during the sintering process of raw mixtures.The concentration of heavy metal in C3S after sintering was determined by ICP-AES.The experimental results indicate that heavy metal doping contributes to a higher symmetry of C3S except for Pb.Addition of up to 3.0wt%,Cr will lead to a decomposition of C3S into C2S and CaO;Zn will cause a transformation from T1 to M2 polymorph,and then to R polymorph;Cu and Ni cause a gradual transformation from T1 to T2 and then to M1 and/or M2 polymorph.During the sintering process,all the Pb releases into atmosphere because of evaporation.