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《烧结球团》2017,(5)
为了改善钒钛烧结矿的低温还原粉化性能,以承德地区的钒钛粉为主料,采用烧结杯实验方法,研究了配碳量、碱度、w(MgO)和澳大利亚FMG矿粉配比对钒钛烧结矿低温还原粉化性能的影响,建立了配碳量、碱度、w(MgO)以及FMG矿粉配比与低温还原粉化性能指标间的回归模型。结果表明:w(MgO)、配碳量、澳大利亚FMG矿粉配比每增加0.1%,低温还原粉化指数分别提高3.41%、1.76%、0.078%;碱度每增加0.1,低温还原粉化指数提高1.63%,模型误差为3%。随着配碳量、碱度、w(MgO)以及FMG矿粉配比的增加,低温还原粉化性能改善,模型结果为钒钛矿烧结工艺参数优化提供理论指导。 相似文献
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铁矿粉烧结中添加MgO有助于稳定磁铁矿和抑制二次赤铁矿的形成,可以改善烧结矿低温还原粉化性能,但其对烧结矿低温还原过程的影响尚不是十分明确。通过热重法测定不同MgO含量的烧结产物在550℃还原过程中质量的变化,定量地了解MgO对烧结产物低温还原性的影响。同时结合XRD和光学显微镜跟踪试样在还原前后矿物组成、结构及裂纹的变化,揭示了MgO改善烧结矿低温还原粉化的机理。结果表明,MgO对烧结产物低温还原过程的影响与Al_2O_3含量有关,不含Al_2O_3时,MgO抑制烧结产物的低温还原,添加Al_2O_3后,MgO对烧结产物低温还原的抑制作用减弱。另外,烧结产物还原过程中裂纹的形成与烧结产物的矿物组成及结构有关,适当的孔隙有利于减少裂纹的形成,这很好地解释了实际铁矿石烧结生产中添加少量的MgO可以改善烧结矿的低温还原粉化性。 相似文献
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高碱度烧结矿的软熔性能 总被引:1,自引:0,他引:1
根据武钢的原料条件,研究了CaO/SiO_2=1.6~2.4,FeO=8~14%,MgO≈3%的16种高碱度烧结矿的软熔性能和还原后的强度。发现:烧结矿的软熔温度和还原强度随其碱度的提高而提高,在所研究的范围内,烧结矿FeO的含量对其软熔性能没有明显的影响;降低FeO的含量不会降低烧结矿的强度。研究表明:烧结矿在软熔过程中其矿物组成的变化也会影响其高温冶金性能。 相似文献
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试验中研究了钒钛烧结矿的高温冶金性能。试验结果指出,在一定范围内,提高碱度和增加烧结矿中MgO含量来改善钒钛烧结矿高温还原性能及软熔性能是有效的。增加MgO还可抑制硅、钛的还原及碳氮化物的生成,有利于渣铁熔融分离而滴落。钒钛磁铁精矿配入普通富矿粉及适当增加烧结混合料配碳量,可以降低炉渣中TiO_2的活度,增加炉渣的氧化能力,有利渣铁分离。但不利于烧结矿的高温还原性和软熔性能的改善。 相似文献
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The effect of dolomite addition on the properties of sinters produced from a high aluminous iron ore
This study provides a systematic approach to an evaluation of the sinter properties with increased MgO addition for superfluxed sinters produced from a high aluminous ore. The investigation revealed that part or full replacement of limestone by dolomite in the sinter mix leads to a drop in sinter cold strength, reducibility and production rate, but has a favourable influence on low-temperature reduction strength and probably better softening and meltdown properties. The change in sinter mineralogy due to the MgO addition has a paramount influence on the sinter properties. The Gua iron ore having a high alumina content, is easily amenable to sintering and the sinters produced can constitute a good burden material because of their high reducibility, good cold and hot-strength characteristics. Improved production rates can be expected by choosing dolomites having a smaller crystal size or choosing other suitable MgO-bearing materials. A high circulating load should be expected while producing MgO-bearing sinters. 相似文献
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通过对不同MgO含量烧结矿破碎体的筛上、筛下物分布规律的研究,计算得出了烧结矿粒度分布的分形维数,线性相关系数均大于0.97,说明使用分形维数定量表征烧结矿在不同MgO含量条件下的粒度组成是可行的.结果表明:分形维数随着MgO含量的增加而增加,在一定程度上可以定量估测烧结矿中MgO含量的范围,并结合微观结构,合理解释了转鼓强度、成品率和分形维数之间的关系.为更加深入表达不同MgO含量的烧结矿的有关数值模型提供了新的理论依据和研究方法. 相似文献
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《钢铁冶炼》2013,40(7):515-520
AbstractDolomite and other MgO bearing materials are being increasingly used as basic flux constituents for production of fluxed sinters. Addition of flux materials in sinter influences the resultant sinter microstructure and chemical properties. The physical and metallurgical properties of sinter mainly depend on mineralogy of the sinter. Dolomite is the source of double carbonate of calcium and magnesium. Recent studies reveal that, apart from the additional fuel needed, the addition of dolomite and MgO bearing material greatly influences the magnetite content and the properties of the sinter produced. The increasing use of MgO bearing fluxes in the blast furnace burden, and the trend to incorporate a major part of fluxes in the sinter mix led to an investigation of the influence of MgO on sinter properties and productivity. In this study, the systematic investigation has been made on the influence of MgO% (1·4 to 2·6) on sinter mineralogy and sinter properties with dolomite. Microstructural examination of dolomite sinter revealed that hematite and calcium ferrite phases decreased whereas magnetite phase increased with increase in MgO percentage in sinter. From the laboratory pot grate sintering results it was found that sinter reduction degradation index improved whereas tumbler index and reducibility decreased with increase in MgO%. 相似文献
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富矿粉烧结中配加蛇纹石与白云石的对比研究 总被引:3,自引:0,他引:3
采用微型烧结法 ,在实验室条件下研究了富矿粉烧结时配加蛇纹石与白云石对烧结矿矿物结构和物理性能的不同影响 ,分析了它们在烧结矿中的作用和赋存状态 ,并通过烧结杯试验验证了机理研究的结果。 相似文献
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为阐述烧结过程熔融机制和成矿机制,明确MgO、Al2O3质量分数对烧结液相生成和矿物组成的影响是至关重要的。利用Factsage软件计算Fe2O3 SiO2 CaO Al2O3 MgO体系的液相生成,计算氧分压在500Pa时,不同温度,不同MgO、Al2O3质量分数下体系液相生成和液相区分布的影响。通过烧结试验,分析烧结矿的矿相和矿物成分,结合软件计算得出烧结矿中MgO质量分数为2.0%、Al2O3质量分数为3.0%时其液相量、矿相、矿物成分达到最优适合烧结冶炼的标准。 相似文献
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Influence of MgO addition on mineralogy of iron ore sinter 总被引:2,自引:0,他引:2
S. C. Panigrahy P. Verstraeten J. Dilewijns 《Metallurgical and Materials Transactions B》1984,15(1):23-32
The influence of MgO addition on sinter mineralogy was studied on sinters produced in a laboratory installation, with a wide
range of MgO/CaO ratios at several basicity indices [B = (CaO + MgO)/ (SiO2 + A12O3)] between 0.7 to 1.9. The most striking influence of MgO is the suppression of hematite and Ca-ferrite phases and the increase
in magnetite phase. In general, MgO favors the formation of glass and suppresses the precipitation of dicalcium silicates
in favor of Ca-Fe-Mg olivines and pyroxenes. Microprobe studies revealed that most of the Mg was picked up by the magnetite
phase to form mixed spinels of type (Fe, Mg)O · Fe2O3. At a constant basicity index, increased replacement of CaO by MgO also led to increased participation of FeO in the slag
formation process, thus increasing the overall FeO content of sinter. A mechanism for the formation of mixed spinels has been
proposed. The effect on various sinter properties resulting due to change in sinter mineralogy has been outlined.
S. C. PANIGRAHY, with Department of Metallurgy and Metallography, State University of Ghent, Ghent, Belgium at the time the
experiments were carried out 相似文献
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为了研究添加高镁粉时w(MgO)对熔剂性球团矿冶金性能的影响。考察了w(MgO)为1.6%~2.4%时,其对球团矿抗压强度、RI(还原性指数)、RDI(低温还原粉化指数)和RSI(还原膨胀指数)的影响。采用光学显微镜和X射线衍射仪对球团矿微观结构和矿物组成进行了分析。结果表明,随着MgO质量分数的增加,抗压强度呈先升高后降低的趋势,w(MgO)为2.0%时,抗压强度最大,为3 533 N;随着w(MgO)由1.6%增加到2.4%,球团矿RI、RDI和RSI得到改善;w(MgO)为1.8%~2.0%时,球团矿微观形貌和矿物组成较好,赤铁矿成片结晶,球团矿强度良好。在用高镁粉和研山精粉造球时,w(MgO)控制为1.8%~2.0%,以期得到较低的还原膨胀指数和较好的冶金性能。 相似文献