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利用基础烧结设备检测了细粒级铁矿粉同化速度、流动能力,并通过微型烧结杯模拟料层下部单元点烧结过程的方法来研究配加15%细粒级矿粉的烧结矿结构变化,有效分析了3种细粒级矿粉在烧结时的液相行为及对烧结矿结构和性能的影响。通过比较生产用混匀矿与配加质量分数为15%的A、B、C粉的烧结矿结构表明:A粉有利于减少烧结矿内部孔洞的尺寸,减少核颗粒和液相间较大孔洞的数量,并能促进针铁矿发展;B粉会增加烧结矿内部大孔洞,增加柱状或片状铁酸钙的生成;C粉同化速度慢,液相流动能力差,粘结效果差,会使液相与核颗粒间孔洞尺寸和数量增加。烧结杯试验结果表明:在生产用混匀矿中使用质量分数为15%的A粉,烧结矿的转鼓指数提高2.94%,低温还原粉化指数(RDI)降低3.37%。 相似文献
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《钢铁研究学报》2020,(7)
为减少因低品位废弃含镍矿堆积而产生的重金属污染和镍资源浪费,同时达到有效利用固废资源及改善褐铁矿型红土镍矿烧结性能的目的,在研究两者基本物化性能及矿物赋存状态的基础上,对比了褐铁矿型红土镍矿无铺底料烧结工艺、烧结矿铺底料烧结工艺及废弃块矿铺底料烧结工艺各项指标,并揭示了相关机制。结果表明:相对于无铺底料烧结工艺及烧结矿铺底料烧结工艺,采用废弃块矿作为铺底料能更为有效地改善褐铁矿型红土镍矿烧结性能,烧结矿转鼓强度分别提高10.16%、3.82%,利用系数分别增加13.40%、6.80%,固体燃耗分别降低9.64%、9.20%;同时,烧结矿冶金性能优异,RI和RDI_(+3.15 mm)分别高达78.24%及96.79%。固结机制研究发现:相对于其他2种工艺,废弃块矿铺底料烧结工艺中,烧结矿微观结构由大孔薄壁结构转化为大孔厚壁结构,且孔洞趋于规则的圆形;另外,SFCA面积分数由7.27%、8.78%增至12.21%,并沿孔洞边缘向内部发展,主要固相—铁尖晶石晶粒有所长大,彼此之间连结程度较好,能更为有效地被液相所润湿,烧结矿微观结构更为紧密,从而使得烧结矿强度进一步提高。而强度更高的块矿作为铺底料,料层透气性更为有效地提高,促进了无烟煤的充分燃烧,使得烧结矿固体燃耗大幅降低,利用系数明显改善。 相似文献
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摘要:为减少因低品位废弃含镍矿堆积而产生的重金属污染和镍资源浪费,同时达到有效利用固废资源及改善褐铁矿型红土镍矿烧结性能的目的,在研究两者基本物化性能及矿物赋存状态的基础上,对比了褐铁矿型红土镍矿无铺底料烧结工艺、烧结矿铺底料烧结工艺及废弃块矿铺底料烧结工艺各项指标,并揭示了相关机制。结果表明:相对于无铺底料烧结工艺及烧结矿铺底料烧结工艺,采用废弃块矿作为铺底料能更为有效地改善褐铁矿型红土镍矿烧结性能,烧结矿转鼓强度分别提高10.16%、3.82%,利用系数分别增加13.40%、6.80%,固体燃耗分别降低9.64%、9.20%;同时,烧结矿冶金性能优异,RI和RDI+3.15mm分别高达78.24%及96.79%。固结机制研究发现:相对于其他2种工艺,废弃块矿铺底料烧结工艺中,烧结矿微观结构由大孔薄壁结构转化为大孔厚壁结构,且孔洞趋于规则的圆形;另外,SFCA面积分数由7.27%、8.78%增至12.21%,并沿孔洞边缘向内部发展,主要固相—铁尖晶石晶粒有所长大,彼此之间连结程度较好,能更为有效地被液相所润湿,烧结矿微观结构更为紧密,从而使得烧结矿强度进一步提高。而强度更高的块矿作为铺底料,料层透气性更为有效地提高,促进了无烟煤的充分燃烧,使得烧结矿固体燃耗大幅降低,利用系数明显改善。 相似文献
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加拿大铁精粉由于具有铁品位高、脉石及有害元素含量低等优点,其在烧结过程中使用具有有利条件。采用微型烧结法考察了该铁精粉配比对烧结体固结强度的影响及其机理,并研究了4种富矿粉的细粉液相流动性和粗颗粒吸液性。在此基础上,通过固结试验,探究并验证了烧结体固结强度的改善方法。研究结果表明,将该铁精粉配入混匀料中,大幅降低了黏附粉偏析碱度,减弱了液相流动性,因此恶化了烧结体的固结强度。在固定碱度的条件下,高硅铁矿粉有较高的细粉液相流动性,低气孔率铁矿粉有较弱的粗颗粒吸液性。在配加该铁精粉的条件下,选择高液相流动性铁矿粉、弱吸液性铁矿粉、强吸液性铁矿粉粗颗粒分加制粒均能有效改善烧结体的固结强度。 相似文献
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Effect of Size Parameters of Mix Ingredients on the Porosity and Reduction Characteristics of Sinter
Ram P. Bhagat Uday S. Chattoraj Manik C. Goswami Deo P. Singh Samir K. Sil 《国际钢铁研究》2007,78(6):451-454
The paper aims to describe the effect of size parameters of the mix ingredients on the tumbler index, porosity and reduction properties of sinter. These parameters are important factors for the furnace performance when the sinter is fed as burden material Understandably, the fines generated inside the furnace in the stack zone or during reduction affect the permeability of the stack zone, which results in a decrease in driving rate and CO utilisation. Pot sintering studies were carried out using hematite ore mix from typical mines in India. The sinter basicity (CaO/SiO2) and MgO content in the sinter were kept at 2.1 and 1.5% respectively. The effect of the size parameters of the mix ingredients, namely size of coke, size of ore fines and that of limestone, on the porosity and quality parameters of sinter was investigated. The studies have shown that reducibility of sinter was well correlated with the proportion of micro‐pores out of total pores available in the sinter. Micro‐porosity of the sinter samples and their reducibility increased with decrease in the size range of coke breeze. Sintering of ore fines with reduced size, also, increased the sinter micro‐porosity. Besides, the average pore radius and density of the sinter sample and consequently the sinter reducibility increased with decreasing ore size. When the size of flux was narrowed down to –3+0.5 mm from –3 mm, the reduction degradation index value declined from 26.8% to 25.6% with marginal decrease in sinter reducibility. Moreover, the speed of sintering increased as well. 相似文献
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澳富粉粒度很细,配入冀东铁精矿中烧结,使烧结矿质量下降。为改善烧结矿质量,在实验室进行了提高配碳量、增加高硅球团返矿量和提高碱度的试验研究。结果认为,提高碱度是最有效的措施。 相似文献
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Iron ore sinter constitutes a major proportion of blast furnace burden. Hence, its quality and consistency have a significant impact on blast furnace performance. Iron ore fines are the main source for sinter, and the chemical composition of the iron ore fines, together with the thermal conditions that blends are subjected to, plays an important role in forming the primary melt during the sintering process and accordingly determines the sinter structure and quality. Therefore, considerable importance has been placed on the chemical composition and consistency of iron ore fines, particularly in terms of alumina content. Due to depletion of high grade iron ore resources, alumina content in the iron ore fines is expected to increase gradually. Ore with higher alumina content is usually expected to be detrimental in forming the sinter matrix, if sintered alone, due to the low reactivity of alumina bearing minerals and the high viscosity of primary melts. The selective granulation process is a new sintering process for high alumina iron ore fines, and can eliminate the adverse effects of ‘hard to sinter’ or ‘unsuitable – for ironmaking’ ores. In the present work laboratory sintering experiments have been carried out with iron ore fines of different alumina level (2.00 to 5.46 mass‐%) to know the influence of alumina on mineralogy, productivity, physical and metallurgical properties of sinter prepared by the conventional and the selective granulation process. With increasing alumina content in sinter of both the conventional and selective granulation process, the fractions of hematite and of silico‐ferrites of calcium and alumina (SFCA) as well as the pore phase increased whereas the magnetite and silicate phases decreased. With increase in alumina content sinter productivity and tumbler index (T.I.) decreased, and metallurgical properties like sinter RDI and reducibility improved. However, sinter of the selective granulation process showed better results compared to the conventional process. 相似文献
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随着鞍钢自产铁精矿供应量逐年减少,扩大进口矿用量成为必然。本文根据鞍钢炼铁总厂烧结车间和西区烧结车间的原料条件,在实验室进行了配加巴西南部粉矿的烧结杯试验研究。结果表明:(1)配加巴西粉矿后超过20%后,烧结矿的转鼓强度下降幅度明显。随着巴西南部粉矿配比增加,垂直烧结速度增大,利用系数提高,燃耗略有提高。(2)相同配比条件下,配矿C方案时烧结矿转鼓要高于A、B方案,但烧结速度较慢、烧结机利用系数低,烧结燃耗增加。(3)配加巴西粉矿后超过20%后,烧结矿的低温还原粉化趋于严重。相同配比条件下,配矿C方案时烧结矿低温还原粉化最优。据此认为:采用巴西南部粉矿配比不超过20%时,可获得较好的烧结指标。工业应用中应避免采用B配矿方案。 相似文献
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为了解巴西CVRD粉矿比例降低对烧结的影响,在试验室条件下进行了5组烧结试验研究,包括烧结矿的冶金性能试验以及矿物组成及结构的研究。研究表明,配用20%巴西CVRD粉矿的第4组烧结矿较为理想,采用澳粉3代替部分巴西CVRD粉矿是可行的;5组烧结矿都是以铁酸钙为主要粘结相的高品位烧结矿,具有较高的强度;在高碱度、高料层的烧结工艺条件下,马钢烧结配矿时可以部分降低巴西CVRD粉矿,对烧结矿质量指标影响不大。 相似文献