The phenomena of tuyere upward-warp have been found at No.6 blast furnace in Kunming Steel Company China after its blow-in, which has made a great impact on the practical production of the furnace. Thus, a number of e...The phenomena of tuyere upward-warp have been found at No.6 blast furnace in Kunming Steel Company China after its blow-in, which has made a great impact on the practical production of the furnace. Thus, a number of efforts have been made to elucidate the mechanism of this phenomenon. The results of investigation and tests revealed that the enrichment and expansion of zinc in the tuyere bricks is the main factor leading to the tuyere upward-warp. The eroding behavior of zinc is that the inner structure of the tuyere bricks turns from dense to loose with entering, enriching and expanding of zinc, which forms spot-like→stripe-like→ditch-like→vein-like→tumorlike eroding passage. Additionally, it is found that the sequence of deleterious ele- ments entering the tuyere refractory is K, Na, Zn and Pb, respectively. Finally, the phenomena and process of zinc crystallization and growth in the refractory have been clearly observed and recorded during this investigation.展开更多
The electrochemical behavior of Mengzi lead-silver-zinc ore flotation system was studied. Based on the electrochemical characteristics of sulfide mineral flotation system, a stage potential control flotation was devel...The electrochemical behavior of Mengzi lead-silver-zinc ore flotation system was studied. Based on the electrochemical characteristics of sulfide mineral flotation system, a stage potential control flotation was developed with the main parameters of pulp potential(φp), pH value and collector dosage. Using N,N’ diphenylamino-dithiolphosphoric acid(NNDDC) as a collector, which has good selectivity for galena flotation at pH 8.8 and pulp potential 330 mV, DDTC is used as secondary collector to improve both the grade and recovery of Pb and Ag. The pulp potential values significantly influence the floatability of practical minerals and single minerals when using NNDDC as the collector. The flotation recovery of galena reaches 85% at about 0.3 V and pH8.8. With the usage of pulp potential control during grinding and flotation, the new pulp electrochemical technology for Mengzi lead-silver-zinc ore flotation was developed. The results show that the grades of Pb and Ag of galena concentrate are 55% and 1 800 g/t, respectively, while the recoveries of Pb and Ag are 86.5% and 65%, respectively, the grade of Zn of marmatite concentrate is 42.5%, and the recovery of Zn is 91.25%.展开更多
FCLS (Ferric Chromium Lignin Sulfonate) was used to aid the separation of chalcopyrite from marmatite. Flotation, adsorption and zeta-potential tests of treated marmatite and chalcopyrite were performed. The flotation...FCLS (Ferric Chromium Lignin Sulfonate) was used to aid the separation of chalcopyrite from marmatite. Flotation, adsorption and zeta-potential tests of treated marmatite and chalcopyrite were performed. The flotation of marmatite was strongly depressed, while that of chalcopyrite was only slightly depressed, over a wide range of pH values when FCLS was used as depressant in the presence of Butyl Xanthate (BX). The adsorption of BX onto chalcopyrite or marmatite takes place over a wide pH range. The adsorption density of BX on chalcopyrite and marmatite decreases as the pH increases. The adsorption density of FCLS onto marmatite is greater than the adsorption density onto chalcopyrite. The zeta potentials of chalcopyrite and marmatite become more negative due to the addition of xanthate and FCLS.展开更多
The flotation behavior of jamesonite was investigated with sodium diethyldithiocarbamate(DDTC) as a collector. The results show that jamesonite has good floatability from pH 2 to pH 13. The flotation of jamesonite is ...The flotation behavior of jamesonite was investigated with sodium diethyldithiocarbamate(DDTC) as a collector. The results show that jamesonite has good floatability from pH 2 to pH 13. The flotation of jamesonite is also dependent on the pulp potential. The potential-pH range for jamesonite flotation is established. The FTIR spectroscopy analysis shows that the major adsorption product of sodium diethyldithiocarbamate on jamesonite is lead diethyldithiocarbamate. The intensity of the FTIR signals of metal diethyldithiocarbamate adsorption on jamesonite and the flotation response of jamesonite are correlated with the pulp potential.展开更多
The mechanism of attachment and leaching of thiobacillus ferrooxidans(T.f.) on chalcopyrite were studied. The shaking flasks with bacteria were observed by SEM. The process of T.f attached to the surface of the mine...The mechanism of attachment and leaching of thiobacillus ferrooxidans(T.f.) on chalcopyrite were studied. The shaking flasks with bacteria were observed by SEM. The process of T.f attached to the surface of the mineral sample and the biofilm forming were described. The promoting role of the biofilm for bioleaching was discussed. The existence of Fe2+ in the exopolysaccharide layer of T.f was demonstrated by EM(electronic microscope)cell-chemistry analysis. These results show that under the proper growth condition of bacteria, bioleaching of chalcopyrite results in the formation of complete biofilm after 23 weeks. There are iron ions in the outer layer polymer of T.f., which provides the micro-environment for themselves, and can guaruntee the energy needed for the bacteria growth in the biofilm. At the same time, Fe3+ions produced oxidize sulfide which brings about the increase of both growth rate of the bacterial and leaching rate of sulfide minerals.展开更多
基金supported by Program for New Century Excellent Talents in University(NCET-2008-0099)
文摘The phenomena of tuyere upward-warp have been found at No.6 blast furnace in Kunming Steel Company China after its blow-in, which has made a great impact on the practical production of the furnace. Thus, a number of efforts have been made to elucidate the mechanism of this phenomenon. The results of investigation and tests revealed that the enrichment and expansion of zinc in the tuyere bricks is the main factor leading to the tuyere upward-warp. The eroding behavior of zinc is that the inner structure of the tuyere bricks turns from dense to loose with entering, enriching and expanding of zinc, which forms spot-like→stripe-like→ditch-like→vein-like→tumorlike eroding passage. Additionally, it is found that the sequence of deleterious ele- ments entering the tuyere refractory is K, Na, Zn and Pb, respectively. Finally, the phenomena and process of zinc crystallization and growth in the refractory have been clearly observed and recorded during this investigation.
文摘The electrochemical behavior of Mengzi lead-silver-zinc ore flotation system was studied. Based on the electrochemical characteristics of sulfide mineral flotation system, a stage potential control flotation was developed with the main parameters of pulp potential(φp), pH value and collector dosage. Using N,N’ diphenylamino-dithiolphosphoric acid(NNDDC) as a collector, which has good selectivity for galena flotation at pH 8.8 and pulp potential 330 mV, DDTC is used as secondary collector to improve both the grade and recovery of Pb and Ag. The pulp potential values significantly influence the floatability of practical minerals and single minerals when using NNDDC as the collector. The flotation recovery of galena reaches 85% at about 0.3 V and pH8.8. With the usage of pulp potential control during grinding and flotation, the new pulp electrochemical technology for Mengzi lead-silver-zinc ore flotation was developed. The results show that the grades of Pb and Ag of galena concentrate are 55% and 1 800 g/t, respectively, while the recoveries of Pb and Ag are 86.5% and 65%, respectively, the grade of Zn of marmatite concentrate is 42.5%, and the recovery of Zn is 91.25%.
基金Financial supports are the National High Technology Research and Development Program of China (No.2006AA06Z120)the Graduate Student Education Innovation of Central South University (No.1343-74334000028)
文摘FCLS (Ferric Chromium Lignin Sulfonate) was used to aid the separation of chalcopyrite from marmatite. Flotation, adsorption and zeta-potential tests of treated marmatite and chalcopyrite were performed. The flotation of marmatite was strongly depressed, while that of chalcopyrite was only slightly depressed, over a wide range of pH values when FCLS was used as depressant in the presence of Butyl Xanthate (BX). The adsorption of BX onto chalcopyrite or marmatite takes place over a wide pH range. The adsorption density of BX on chalcopyrite and marmatite decreases as the pH increases. The adsorption density of FCLS onto marmatite is greater than the adsorption density onto chalcopyrite. The zeta potentials of chalcopyrite and marmatite become more negative due to the addition of xanthate and FCLS.
基金supported by the National Key Fundamental Research and Development Program(No.2005CB623701)the National Department Public Benefit Research Foundation from Ministry of Land and Resources(No.201011031 )the Foundation for the Author of Zhengzhou Institute of Multipurpose Utilization of Mineral Resources CAGS(No.2935)
基金Project(50234010) supported by the National Natural Science Foundation of China
文摘The flotation behavior of jamesonite was investigated with sodium diethyldithiocarbamate(DDTC) as a collector. The results show that jamesonite has good floatability from pH 2 to pH 13. The flotation of jamesonite is also dependent on the pulp potential. The potential-pH range for jamesonite flotation is established. The FTIR spectroscopy analysis shows that the major adsorption product of sodium diethyldithiocarbamate on jamesonite is lead diethyldithiocarbamate. The intensity of the FTIR signals of metal diethyldithiocarbamate adsorption on jamesonite and the flotation response of jamesonite are correlated with the pulp potential.
文摘The mechanism of attachment and leaching of thiobacillus ferrooxidans(T.f.) on chalcopyrite were studied. The shaking flasks with bacteria were observed by SEM. The process of T.f attached to the surface of the mineral sample and the biofilm forming were described. The promoting role of the biofilm for bioleaching was discussed. The existence of Fe2+ in the exopolysaccharide layer of T.f was demonstrated by EM(electronic microscope)cell-chemistry analysis. These results show that under the proper growth condition of bacteria, bioleaching of chalcopyrite results in the formation of complete biofilm after 23 weeks. There are iron ions in the outer layer polymer of T.f., which provides the micro-environment for themselves, and can guaruntee the energy needed for the bacteria growth in the biofilm. At the same time, Fe3+ions produced oxidize sulfide which brings about the increase of both growth rate of the bacterial and leaching rate of sulfide minerals.