In the present paper,the fundamental research on the properties of boron-rich slag melting separated from boron-bearing iron concentrate was performed.The melting and fluidity of B2O3–MgO–SiO2–FeO slag system,cryst...In the present paper,the fundamental research on the properties of boron-rich slag melting separated from boron-bearing iron concentrate was performed.The melting and fluidity of B2O3–MgO–SiO2–FeO slag system,crystallization of separated boron-rich slag and factors on the extraction efficiency of boron-rich slag were systematically investigated.B2O3 content would heavily affect the melting and fluidity property of boron-rich slag.Generally,FeO could improve the melting and fluidity property of boron-rich slag.Boron-containing crystalline phase mainly precipitated in temperature range from 1200°C to 1100°C.Higher smelting temperature and B2O3 reduction ratio were negative for the extraction of boron.The cooling rate of 10–20°C/min was better for the crystallization of boron-containing crystalline phase.Based on the obtained experimental results,the optimum operating parameters for the development of pyrometallurgical boron and iron separation process and further boron-rich slag cooling process were proposed.展开更多
The effect of composite agglomeration process(CAP) on fluoric iron concentrates sintering was investigated.The yield and quality of the sinter are greatly improved when using CAP assisted with heat airflow and enhanci...The effect of composite agglomeration process(CAP) on fluoric iron concentrates sintering was investigated.The yield and quality of the sinter are greatly improved when using CAP assisted with heat airflow and enhancing magnesium oxide(MgO) contents.For conventional sintering of fluoric iron concentrate,due to lower viscosity of binding phase and higher fluidity of liquid phase,the sinter is formed with large thin-walled holes and the strength of the sinter is deteriorated consequently.The novel process forms composite agglomerate in which acid pellets are embedded in basic sinter.The pellets are solid with interconnecting crystals of hematite(Fe2O3) and magnetic(Fe3O4).For basic sintering,after adding MgO,the viscosity of the melting phase increases and the fluidity decreases;and calcium and aluminum silico-ferrites and magnesium ferrite are formed with perfect crystals and good sintering microstructure.展开更多
Carboxylmethyl cellulose(CMC) has become a commercial organic binder in agglomeration of iron ore concentrates. The relative molecular mass and degree of substitution(DS) of CMC have a large impact on its binding perf...Carboxylmethyl cellulose(CMC) has become a commercial organic binder in agglomeration of iron ore concentrates. The relative molecular mass and degree of substitution(DS) of CMC have a large impact on its binding performance. The interaction mechanism between CMC and iron ore particles was analyzed through Zeta potential measurements, adsorption measurements and infrared spectra. The results show that the interaction is chemical adsorption-oriented and the CMC's adsorption performance is related to the properties of CMC as well as the type of iron oxides. CMC has a greater affinity to Fe2O3 than Fe3O4, and CMC with higher relative molecular mass shows a higher adsorption isotherm. Pelletization of practical iron ore concentrates added with CMC further illustrates that CMC with higher relative molecular mass or DS exhibits a better binding performance, which is consistent with the results of adsorption tests.展开更多
基金Project(FRF-TP-16-019A1)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(51274033)supported by the National Natural Science Foundation of China
文摘In the present paper,the fundamental research on the properties of boron-rich slag melting separated from boron-bearing iron concentrate was performed.The melting and fluidity of B2O3–MgO–SiO2–FeO slag system,crystallization of separated boron-rich slag and factors on the extraction efficiency of boron-rich slag were systematically investigated.B2O3 content would heavily affect the melting and fluidity property of boron-rich slag.Generally,FeO could improve the melting and fluidity property of boron-rich slag.Boron-containing crystalline phase mainly precipitated in temperature range from 1200°C to 1100°C.Higher smelting temperature and B2O3 reduction ratio were negative for the extraction of boron.The cooling rate of 10–20°C/min was better for the crystallization of boron-containing crystalline phase.Based on the obtained experimental results,the optimum operating parameters for the development of pyrometallurgical boron and iron separation process and further boron-rich slag cooling process were proposed.
基金Project(50725416) supported by the National Science Fund for Distinguished Young Scholars
文摘The effect of composite agglomeration process(CAP) on fluoric iron concentrates sintering was investigated.The yield and quality of the sinter are greatly improved when using CAP assisted with heat airflow and enhancing magnesium oxide(MgO) contents.For conventional sintering of fluoric iron concentrate,due to lower viscosity of binding phase and higher fluidity of liquid phase,the sinter is formed with large thin-walled holes and the strength of the sinter is deteriorated consequently.The novel process forms composite agglomerate in which acid pellets are embedded in basic sinter.The pellets are solid with interconnecting crystals of hematite(Fe2O3) and magnetic(Fe3O4).For basic sintering,after adding MgO,the viscosity of the melting phase increases and the fluidity decreases;and calcium and aluminum silico-ferrites and magnesium ferrite are formed with perfect crystals and good sintering microstructure.
基金Project(2012zzts101)supported by the Fundamental Research Funds for the Central Universities,China
文摘Carboxylmethyl cellulose(CMC) has become a commercial organic binder in agglomeration of iron ore concentrates. The relative molecular mass and degree of substitution(DS) of CMC have a large impact on its binding performance. The interaction mechanism between CMC and iron ore particles was analyzed through Zeta potential measurements, adsorption measurements and infrared spectra. The results show that the interaction is chemical adsorption-oriented and the CMC's adsorption performance is related to the properties of CMC as well as the type of iron oxides. CMC has a greater affinity to Fe2O3 than Fe3O4, and CMC with higher relative molecular mass shows a higher adsorption isotherm. Pelletization of practical iron ore concentrates added with CMC further illustrates that CMC with higher relative molecular mass or DS exhibits a better binding performance, which is consistent with the results of adsorption tests.
