文章就包钢500 m 2烧结机基于不同SiO_(2)含量在烧结矿中的作用,进行了烧结矿SiO_(2)含量为4.75%、4.85%、4.95%、5.15%、5.30%的烧结生产,结果表明:烧结矿中SiO_(2)含量小于5.15%时,随着烧结矿SiO_(2)含量逐步增加,烧结矿转鼓强度提高;...文章就包钢500 m 2烧结机基于不同SiO_(2)含量在烧结矿中的作用,进行了烧结矿SiO_(2)含量为4.75%、4.85%、4.95%、5.15%、5.30%的烧结生产,结果表明:烧结矿中SiO_(2)含量小于5.15%时,随着烧结矿SiO_(2)含量逐步增加,烧结矿转鼓强度提高;在SiO_(2)含量为5.15%左右时烧结矿转鼓强度达到最佳,较SiO_(2)含量为4.75%时提高了3%,平均粒径提高1.77 mm;当烧结矿SiO_(2)含量从5.15%增加至5.30%以上时,随着SiO_(2)含量继续增加,转鼓强度变化不大。综合不同SiO_(2)含量的烧结矿显微结构分析,随着SiO_(2)含量的增加,板柱状的铁酸钙增加,当SiO_(2)含量增加到5.30%左右,部分区域硅酸二钙大面积富集。在包钢烧结高自产精矿比例条件下,控制烧结矿SiO_(2)含量为5.15%左右,烧结矿转鼓强度可以达到79.5%以上,平均粒径可以提高到19 mm以上。展开更多
Mineral compositions and microstructures of fluorine bearing magnetite concentrate and vanadium titanomagnetite concentrate are studied. The results show that a boride and a catalytic oxidation agent have great effect...Mineral compositions and microstructures of fluorine bearing magnetite concentrate and vanadium titanomagnetite concentrate are studied. The results show that a boride and a catalytic oxidation agent have great effects on ameliorating the mineral compositions and microstructures of these sinters, and the catalytic agent is more effective. Comparing these two kinds of ores, the performance of fluorine bearing magnetite concentrate is better. Addition of 0.01% catalyst into fluorine bearing magnetite concentrate can increase calcium ferrite content from 15% 20% up to 34% 39%, and its microstructure changes from large cavities and thin framework into intermediate cavities and thick framework, and the microcracks disappear.展开更多
Iron ore containing BaSO_(4) may have a series of effects on the quality of the sinter and performance of the blast furnace.Thus,the effect mechanism of BaSO_(4)(0-6.0 mass%)on the compressive strength,mineral composi...Iron ore containing BaSO_(4) may have a series of effects on the quality of the sinter and performance of the blast furnace.Thus,the effect mechanism of BaSO_(4)(0-6.0 mass%)on the compressive strength,mineral composition,and microstructure of the sinter was investigated.The experimental results show that the compressive strength of the sintered samples initially increases and then decreases when the BaSO_(4) content increases from 0 to 6.0 mass%,reaching a peak value of 12.78 kN with a BaSO_(4) content of 1.0 mass%.Thermal analysis indicates that BaSO_(4) initially decomposes to produce BaO at 1468 K in the presence of iron ore.BaO combines with Fe_(2)O_(3) forming barium ferrite(Ba_(2)Fe_(6)O_(11)),which exists in the sintered sample with a granular form.BaO also dissolves in calcium ferrite and slag to promote the formation of calcium ferrite and barium glass,respectively.The content of needle-like calcium ferrite gradually increases and then decreases with the increase in BaSO_(4) content.Hematite exists in a plate-like form.The generation of dicalcium ferrite is promoted by increasing the BaSO_(4) addition from 2.0 to 6.0 mass%.展开更多
This study investigated the interdiffusion of calcium ferrite/calcium titanate system in the time range of 0-120 min by the diffusion couple method in a CO/N2 reducing atmosphere at 700℃.The results show that after t...This study investigated the interdiffusion of calcium ferrite/calcium titanate system in the time range of 0-120 min by the diffusion couple method in a CO/N2 reducing atmosphere at 700℃.The results show that after the diffusion reaction occurred,no longitudinal agglomerations were present on the substrate surface on the calcium titanate side.When the diffusion time was increased to 105 min,a net vacancy flow from calcium titanate to calcium ferrite might have occurred,causing the surface of the calcium ferrite substrate to collapse.The thickness of the diffusion layer of the calcium ferrite/calcium titanate system was about 17-48μm,which conforms to the parabolic law of diffusion.The diffusion coefficient and the Ti^4+concentration in the calcium ferrite/calcium titanate system are related.This shows an increase in the diffusion coefficient with the increase of Ti^4+concentration,and the diffusion coefficient value was in the range of 10^−12-10^−11 cm^2·s^−1.展开更多
文摘文章就包钢500 m 2烧结机基于不同SiO_(2)含量在烧结矿中的作用,进行了烧结矿SiO_(2)含量为4.75%、4.85%、4.95%、5.15%、5.30%的烧结生产,结果表明:烧结矿中SiO_(2)含量小于5.15%时,随着烧结矿SiO_(2)含量逐步增加,烧结矿转鼓强度提高;在SiO_(2)含量为5.15%左右时烧结矿转鼓强度达到最佳,较SiO_(2)含量为4.75%时提高了3%,平均粒径提高1.77 mm;当烧结矿SiO_(2)含量从5.15%增加至5.30%以上时,随着SiO_(2)含量继续增加,转鼓强度变化不大。综合不同SiO_(2)含量的烧结矿显微结构分析,随着SiO_(2)含量的增加,板柱状的铁酸钙增加,当SiO_(2)含量增加到5.30%左右,部分区域硅酸二钙大面积富集。在包钢烧结高自产精矿比例条件下,控制烧结矿SiO_(2)含量为5.15%左右,烧结矿转鼓强度可以达到79.5%以上,平均粒径可以提高到19 mm以上。
文摘Mineral compositions and microstructures of fluorine bearing magnetite concentrate and vanadium titanomagnetite concentrate are studied. The results show that a boride and a catalytic oxidation agent have great effects on ameliorating the mineral compositions and microstructures of these sinters, and the catalytic agent is more effective. Comparing these two kinds of ores, the performance of fluorine bearing magnetite concentrate is better. Addition of 0.01% catalyst into fluorine bearing magnetite concentrate can increase calcium ferrite content from 15% 20% up to 34% 39%, and its microstructure changes from large cavities and thin framework into intermediate cavities and thick framework, and the microcracks disappear.
基金financially supported by National Natural Science Foundation of China(Grant No.51604209)Natural Science Basic Research Program of Shaanxi(Program No.2019JLP-05).
文摘Iron ore containing BaSO_(4) may have a series of effects on the quality of the sinter and performance of the blast furnace.Thus,the effect mechanism of BaSO_(4)(0-6.0 mass%)on the compressive strength,mineral composition,and microstructure of the sinter was investigated.The experimental results show that the compressive strength of the sintered samples initially increases and then decreases when the BaSO_(4) content increases from 0 to 6.0 mass%,reaching a peak value of 12.78 kN with a BaSO_(4) content of 1.0 mass%.Thermal analysis indicates that BaSO_(4) initially decomposes to produce BaO at 1468 K in the presence of iron ore.BaO combines with Fe_(2)O_(3) forming barium ferrite(Ba_(2)Fe_(6)O_(11)),which exists in the sintered sample with a granular form.BaO also dissolves in calcium ferrite and slag to promote the formation of calcium ferrite and barium glass,respectively.The content of needle-like calcium ferrite gradually increases and then decreases with the increase in BaSO_(4) content.Hematite exists in a plate-like form.The generation of dicalcium ferrite is promoted by increasing the BaSO_(4) addition from 2.0 to 6.0 mass%.
基金This work was financially supported by the National Natural Science Foundation of China(No.51674084).
文摘This study investigated the interdiffusion of calcium ferrite/calcium titanate system in the time range of 0-120 min by the diffusion couple method in a CO/N2 reducing atmosphere at 700℃.The results show that after the diffusion reaction occurred,no longitudinal agglomerations were present on the substrate surface on the calcium titanate side.When the diffusion time was increased to 105 min,a net vacancy flow from calcium titanate to calcium ferrite might have occurred,causing the surface of the calcium ferrite substrate to collapse.The thickness of the diffusion layer of the calcium ferrite/calcium titanate system was about 17-48μm,which conforms to the parabolic law of diffusion.The diffusion coefficient and the Ti^4+concentration in the calcium ferrite/calcium titanate system are related.This shows an increase in the diffusion coefficient with the increase of Ti^4+concentration,and the diffusion coefficient value was in the range of 10^−12-10^−11 cm^2·s^−1.
