浮选赤铁精矿烧结节能降耗的实践

赤铁矿烧结主要是还原再氧化反应过程，与磁铁矿烧结相比，其能源消耗较高。用浮选法选别后的赤铁精矿具有细、粘等特点，烧结过程中表现为混匀难、造球难、烧结难、能耗高。本文介绍了鞍钢矿业集团东烧厂采用这种浮选赤铁细精矿烧结的节能降耗经验和措施。     

攀枝花铁精矿烧结强化与烧结过程的研究

根据冷态模型试验和φ250毫米烧结杯试验,并通过烧结过程解剖,研究和讨论了以下问题: 1) 细磨钒钛铁精矿对强化制粒,改善混合料透气性的效果及其影响因素。关于烧结混合料制粒小球的结构; 2) 细磨钒钛铁精矿的烧结性能; 3) 烧结料层厚度与负压对烧结过程的影响; 4) 不民碱度的钒钛烧结矿及添加氧化镁的钒钛烧结矿的烧结特性与产品的冶金性能; 5) 钒钛铁精矿烧结过程料层温度与压力的变化规律。烧结过程各带的形成与矿物生成的特点。     

粘结剂强化高配比镜铁精矿烧结研究

就添加不同种类粘结剂,以强化镜铁精矿制粒,从而提高镜铁精矿在烧结料中的配比进行了试验研究。结果表明:在镜铁精矿配比为36%时,添加有机、无机或有机无机复合粘结剂均可改善烧结料层透气性,垂直烧结速度可提高1.08~2.62 mm/min,利用系数增加了0.03~0.14 t/(m~2·h),烧结矿转鼓强度达到67%~72%,固体燃耗则降低2.82~4.01 kg/t。其中,有机无机复合粘结剂综合效果最佳。     

海南铁精矿烧结研究

对海南铁精矿适宜的烧结工艺参数及强化措施进行了研究，研究表明：海南铁精矿作为烧结原料时，烧结利用系数低，燃耗高，脱硫率低，而且精矿配比最高不能超过７０％，料高以４００ｍｍ为宜，配加澳矿是改善海南铁精矿结矿质量的重要途径，焦粉分加是降低燃耗的主要措施，较高料层时，有机粘结剂可以强化制粒，改善料层透气性。     

铁精矿烧结新工艺研究

以近北庄为主的磁铁精矿的球团烧结进行了较全面的实验室探索，结果表明，球团烧强工艺可以用普通粒度结燃料和全部磁铁精矿生产出碱度不同的优质烧结矿。     

冀东铁精矿配加细粒澳富粉烧结试验

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。     

高压辊磨强化赤铁精矿制备氧化球团的研究

以巴西某赤铁精矿为主要原料,在系统研究赤铁矿制备氧化球团特性的基础上,针对其生球强度差、焙烧温度高以及成品球强度差等问题,系统研究了高压辊磨预处理对其成球性能和焙烧性能的影响及规律,并从颗粒形貌的角度分析了影响机理.预处理后铁精矿的比表面积可达1 600 cm2/g以上,膨润土用量可降低0.75％,适宜的预热温度可降低...     

巴西赤铁精矿球团试验研究

1前言 到目为止我国球团原料仍然以磁铁精矿为主，但随着球团生产的迅速发展，磁铁精矿产量远远满足不了球团生产的需要。近年有的球团厂在磁铁精矿中配加部分赤铁精矿，但配加的比例较少。加大赤铁精矿配比将是我国今后球团发展的趋势，因此本文对赤铁精矿生产球团矿进行了研究。     

铁精矿粉的烧结及其局部还原

苏联中央黑色冶金科学研究院研史了使用铁精矿粉制造部分由还原铁所组成的烧结团,并且在精矿粉的烧结过程中使用了固体还原剂粉及矿粉煤球,然后在1100～1300℃的温度下烧结。目的是为了得到足够强度的未烧结好的烧结球团并使铁的还原度达     

微波烧结磁铁精矿试验研究

微波能是一种清洁的新型能源,利用微波的热效应进行磁铁精矿微波烧结是一项全新的课题.本文研究了在氮气保护下, 分别配加不同含碳量和改变二元碱度( CaO/SiO2 )的条件下微波烧结精矿粉,并就含碳量和碱度等因素对烧结产品的影响做了分析.得出当二元碱度为2.5时国内精矿试样的烧结产品性能达到了一定的要求,为今后微波烧结磁铁精矿的工业化生产作了探索性研究.     

Study on the sintering melting characteristics of Meishan concentrate and its influencing factors

The melting characteristics of iron ore plays an important role in the process of sintering and mineralization. The softening and melting process of Meishan concentrate, the main mineral in the sintering of Meishan Iron and Steel Company, and four typical imported iron ores were observed through a visual micro-sintering test device. The results show that the Meishan concentrate has a relatively gentle liquid-phase velocity, good liquid-phase temperature control property, and relatively good safety. In addition, with the increase in alkalinity, its melting characteristics become worse. When combined with OA, its melting characteristics became worse, and with OD ore, its melting characteristics had improved in our study. Therefore, based on the principle of optimizing the complementary ore blending, in order to ensure the good temperature control and safety of the Meishan concentrate in the liquid phase of the sintering process, the appropriate sinter basicity and the appropriate type of iron ores should be selected.     

强力混合强化微细粒精矿烧结的工艺试验分析

为了研究强力混合工艺对微细粒精矿粉烧结的作用,针对太钢微细粒精矿为主的烧结原料结构,系统开展了强力混合对制粒效果、烧结指标影响的研究。结果表明,与传统圆筒混合、制粒工艺相比,强力混合因强化了水分的分散和物料混匀,适宜制粒水分明显降低,混合料制粒效果明显改善,制粒强度提升,有利于减少粉尘排放量。对于太钢原料结构而言,适宜的强力混合-制粒工艺流程为圆筒混合+强力混合+圆筒制粒,烧结速度和利用系数大幅提升,烧结效果得到改善。     

赤铁精粉配比对烧结矿强度的影响

 铁精粉具有铁品位高、脉石矿物含量及有害元素少、价格较低等优点，但由于其粒度过细，会对烧结生产产生不良影响，进而导致其使用受到限制。为了明确铁矿烧结过程中赤铁精粉配比对烧结矿强度的影响规律，采用微型烧结法研究了赤铁精粉配比对烧结液相流动性及其固结强度的影响规律，并在此基础上进一步探究了优化石灰石粒度对烧结矿强度的影响规律，最终为高效使用赤铁精粉提供理论基础。研究结果表明，随着赤铁精粉配比的增大，烧结体固结强度呈现先略微降低，而后在配比为15%时大幅下降（相对于配比10%铁精粉来说固结强度降低了16%），这是由于随着赤铁精粉配比的增大，黏附粉的偏析碱度降低，进而使得黏附粉的液相流动性减小，最终导致烧结矿强度降低。然而，减小石灰石粒度，可以有效改善烧结液相流动性，进而提高烧结矿强度。     

Effect of heating pretreatment on ballability of hematite concentrate with flotation process

The experiments were carried out to investigate the mechanism of lower cracking temperature of green pellet made by iron concentrate with flotation process. The results of Fourier transform infrared spectroscopy??FTIR?? analysis indicate that the iron concentrate of green pellet with lowest cracking temperature has the strongest sodium oleate transmittance of infrared spectrum. When the iron concentrate is heated to 70, 150 and 250??, respectively, the sodium oleate transmittance weakens and the cracking temperature of green pellet increases observably. The sodium oleate that attached to the surface of iron concentrate make the iron concentrate more hydrophobic, which leads to faster vaporizing speed of pellets moisture and lower cracking temperature of green pellet. The pretreatment of heating iron concentrate above 150?? can effectively decrease the residual sodium oleate on the surface of iron concentrate and improve the cracking temperature of green pellet.     

Consolidation processes in the sintering of fine-grained iron-copper pseudo-alloys

The properties of fine-grained iron-copper pseudo-alloys (ICPA) and consolidation processes that occur during their sintering are studied. The grains are no larger than 0.5 μm. It was established that the specimens undergo shrinkage, not growth, when fine iron-copper mixtures are sintered within the range 600–1130 °C. This occurs as a result of active consolidation of the dispersed powder mixture, shortening of the diffusion paths, and the active formation of solid solutions based on iron and copper. Sintered ICPAs have a stable fine-grained microstructure with a maximum grain size of 0.5 μm only when they are sintered and treated in the solid phase. A coarse-grained structure is formed when ICPAs are heated to temperatures at which a liquid phase appears. Fine-grained ICPAs are also characterized by high hardness (up to 240–260 HB). Translated from Poroshkovaya Metallurgiya, Nos. 1–2(411), pp. 22–29, January–February, 2000.     

微细精矿比例对烧结的影响及强化技术

为了提高国产铁矿石利用价值,要经过反复细磨,导致铁精矿粉粒度超细,对烧结过程及产量、质量指标影响较大。为了使660 m2烧结机高比例配用微细精矿粉,降低烧结原料成本,满足4350 m3高炉的生产需要,进行了试验研究。研究结果表明：随着微细精矿配用比例的提高,烧结料层透气性恶化,烧结液相生成能力减弱,铁酸钙生成量减小。为此,在优化熔剂结构及燃料粒度的基础上,进行了预成核技术开发应用,将部分精矿粉预先制成制粒核,减少物料中黏附粉的量,以强化物料制粒效果和成矿反应,使烧结矿结构改善。     

Precipitation behavior and its effect on strengthening of an HSLA-Nb/Ti steel

The precipitation behavior of a commercial high-strength low-alloy (HSLA) steel microalloyed with 0.086 wt pct Nb and 0.047 wt pct Ti has been investigated using transmission electron microscopy (TEM) and mechanical testing. The emphasis of this study is to compare an industrially hot-rolled steel and samples from a laboratory hot torsion machine simulation. From TEM observations, the Ti and Nb containing precipitates could be grouped according to their size and shape. The precipitates in order of size were found to be cubic TiN particles with sizes in the range of 1 μm, grain boundary precipitates with diameters of approximately 10 nm, and very fine spherical or needle-shaped precipitates with sizes on the order of 1 nm. The needlelike precipitates were found on dislocations in ferrite and constituted the dominant population in terms of density. Thus, they appear to be responsible for the precipitation strengthening observed in this steel. Aging tests were carried out at 650°C to evaluate the precipitate strengthening kinetics in detail. The strengthening mechanisms can be described with a nonlinear superposition of dislocation and precipitation hardening. The mechanical properties of torsion-simulated material and as-coiled industrial material are similar; however, there are some microstructural differences that can be attributed to the somewhat different processing routes in the laboratory as compared to hot strip rolling.