Production of high carbon ferromanganese using manganese rich slag in the charge

The possibility of replacement of the high cost sinter manganese ore by manganese rich slag for the production of high carbon ferromanganese was experimentally demonstrated. The experimental heats were designed and carried out to optimize this replacement through the adjustment of different production parameters. The results of pilot plant experimental heats showed that replacement of 50% of the sinter in the blend (or 25% of the blend) by slag containing 32% Mn and operation under slag basicity 0.9 and low (MgO)/(CaO) ratio of about 0.2-0.3 are the optimum conditions to attain the highest manganese content in the produced ferromanganese, the highest manganese recovery and the highest metallic yield. The industrial application of reusing manganese slag clarified the economic efficiency of charging manganese slag up to 20-25% of the blend in reducing the production cost due to reducing the cost of manganese ores. Charging of 20-25% manganese slag reduces the cost of manganese ores and the total production cost by about 13 and 6% respectively, comparing with the conventional technology (without using manganese slag in the blend).     

Factors Affecting Silicomanganese Production using Manganese Rich Slag in the Charge

Silicomanganese is widely used as a complex reducer and an alloying addition in the production of various grades of steel due to its economic and metallurgical advantages. It is also used as a semi‐product in the manufacture of medium‐ and low‐carbon ferromanganese and metallic manganese. Manganese‐rich slag, resulting from high carbon ferromanganese production, has the advantages of high manganese content, high Mn/Fe ratio, low excess oxygen, low phosphorus content, low fine content and low cost. Such slag seems to be very attractive to use as raw materials for the production of silicomanganese alloys. In the present study, experimental heats were designed and carried out to optimise the factors affecting the production process of silicomanganese using manganese rich slag in the charge. The results of pilot plant experimental heats showed that the optimum metallic yield and recoveries of manganese and silicon are obtained with an initial slag basicity, (CaO + MgO) / (Al₂O₃), of 1.8 by using dolomite as fluxing material and charging quartzite and fluorspar in percentage of 25% and 4% of the blend, respectively. The results also showed that an amount of 30% of coke in excess of the stoichiometric amount should be added. These results are relative for the specific high Al₂O₃ ores used.     

Smart ore blending methodology for ferromanganese production process

This study is carried out to develop a smart ore blending methodology for high carbon ferromanganese production units. Geometallurgical characterisation of the ores collected from 10 different mines has been carried out to estimate variation in their aptness for the alloy production process. An evolutionary algorithm-based methodology has been adopted for ore blending to maximise the total manganese content of the ore blend under applied physico-chemical constraints. Analysis provides various blends of the same chemical composition but of different geometallurgical ranks. An artificial neural network model has been developed to predict the operational parameters such as slag and metal composition. This method allows the operator to visualise the impact of combinations of different ore blends on slag–metal composition as well as on electric power and coke required for smelting reduction of ores in the submerged arc furnace. It was observed that best blends could reduce power and coke consumption by 100?kWh?ton^?1 and 30?kg?ton^?1, respectively, but optimum values can be established in long run considering conservation of natural resources.     

锰硅合金渣在锰硅合金冶炼中的利用

为合理利用锰硅合金冶炼产生的炉渣,充分利用其CaO、MgO、SiO2、Al2O3含量高及比电阻大等特点,将其搭配入炉,大幅减少白云石、硅石等辅料的加入量;同时提高了入炉Al2O3含量,解决了北方锰矿普遍含Al2O3较低的问题,改善了电极下插条件,提高了锰的回收率及硅的还原率,降低了生产成本,工艺可操作性强。     

优化锰铁高炉配矿结构

介绍了通过优化高炉锰铁烧结矿原料结构，改善了烧结矿性能，使锰铁冶炼取得了增产、节焦、降成本的明显效果。     

转炉终点渣钢间锰平衡状况分析

为了推广锰矿直接还原技术在转炉内的使用,对转炉终点条件下锰矿的热分解、熔融还原和渣钢间平衡状态进行了分析。利用热力学分析方法讨论了国内外转炉锰矿直接合金化锰的平衡状态。结果表明,在转炉终点时刻,锰矿以MnO形式存在于渣中;锰在渣钢间的平衡主要以铁、锰竞争氧化的形式存在;理论计算锰分配比和实践生产数据有相同的趋势,且计算值大于实践生产数据;高温、高碱度、高w([C])、低w((TFe))可以降低锰分配比;渣量越小,锰收得率越高。此外,讨论了进一步提高转炉锰收得率的控制工艺。     

利用锰硅合金粉生产低磷中碳锰铁的理论研究与实验

利用锰硅合金破碎产生的残粉作为生产低磷中碳锰铁的主要原材料,通过分析电硅热法(冷装法)生产中碳锰铁存在的问题和产品碳高、磷高的质量状况,提出了“二步法”脱磷、“二步法”脱硅生产中低碳锰铁的新工艺。根据拟定的工艺实验方案,完成了台架实验和现场模拟实验。实验表明：采用脱磷合金和No．3造渣剂,可以实现MnSi合金同时脱磷、脱碳,合金中磷含量降至0．15％、碳含量降至1．40％以下;脱磷合金用量6％～14％,脱磷率约为18．5％～43．1％;低磷富锰渣预脱硅和锰矿终脱硅的“二步法”熔炼工艺能满足生产低磷中碳锰铁的技术要求。     

锰粉矿烧结配矿工艺及其对产物性能的影响

锰矿是冶炼锰系合金的重要工业原料,目前中国大部分锰铁粉矿均经烧结后入炉冶炼,并且采用的是单烧.为了研究不同锰粉矿掺烧工艺对锰烧结矿性能的影响,并因此得到熔炼性能较优的烧结矿,采用马弗炉烧结法,改变原料配比、碱度、ω(Mn)/ω(Fe)等因素,对3种锰粉矿配矿烧结工艺进行初步研究.采用X射线衍射、光学显微镜以及强度、气孔...     

攀钢冶炼钒钛磁铁矿的炉料结构研究

利用普通高炉冶炼高钛型钒钛磁铁矿有很大的难度。选择合理的炉料结构，控制高含量ＴｉＯ_２的还原，是冶炼该矿石的首要条件。炉料在块状带的还原、高温还原熔化、初渣的生成以及高温带渣铁反应的研究结果和生产实践都表明：提高炉料中ＳｉＯ_２含量，适当配加萤石、铁锰矿或配加部分难还原的矿石都可以改善钒钛烧结矿的冶炼性质。     

微波加热含碳锰矿球团冶炼高碳锰铁的研究

对微波加热含碳锰矿球团冶炼高碳锰铁进行了试验研究,探明配碳系数、炉渣碱度对锰回收率的影响。结果表明,采用微波加热含碳锰矿料球,可以冶炼出符合要求的高碳锰铁合金。配碳系数及炉渣二元碱度对锰元素回收率影响显著,当配碳系数为1.4、炉渣二元碱度为2.0时,锰元素回收率最高可达90%以上。当配碳过量时,锰元素回收率下降明显。     

锰烧结矿最佳三元碱度的研究

针对信阳铁合金厂的条件，试验研究了三元碱度对锰烧结矿的产率、机械强度和粒度组成的影响；对不同碱度的锰烧结矿进行了岩矿相鉴定，分析了矿相组成与烧结矿性能的关系；模拟锰铁高炉的温度分布和煤气化学成分的分布条件，测定了不同碱度实验室锰烧结矿及信阳铁合金厂常用含锰矿物的软熔温度．研究结果表明，三元碱度１７０左右的锰烧结矿的烧结成品率最高，冷强度最高，耐风化能力最强，软熔性能最优良．     

CVRD矿在青钢的应用

巴西 CVRD矿具有含铁品位高、有害杂质少、烧结性能良好的特点。采用 CVRD矿作为烧结配矿的主矿 ,经合理配比和优化工艺参数 ,烧结生产率提高 ,烧结矿质量改善 ,冶金性能提高     

锰矿预热和热装工艺及其应用实践

为降低电耗，提高电炉生产能力，采用回转窑预热锰矿和热装工艺生产富锰渣用于冶炼金属锰和高碳锰铁。此工艺可使产品电耗降低约20％，电炉生产能力提高20％以上。实践证明，回转窑在电炉富锰渣的生产中的应用非常成功，经济效益显著。     

A review of the beneficiation of low-grade manganese ores by magnetic separation

ABSTRACT

Magnetic separation is an effective strategy for the upgrading of a variety of lean ores, including the beneficiation of low-grade manganese ores. This work reviews 24 studies on the magnetic separation of manganese ores; 6 of these studies report both a sufficiently high Mn grade (>44% Mn) and Mn/Fe ratio (>7.5) in the concentrate as to be suitable for use as high-grade feed materials in the production of ferromanganese. Of these 24 studies, the most efficient separation and enrichment was generally achieved by the reduction roasting of the ore prior to magnetic separation, rather than the direct separation of the ore. In both cases there was sufficient evidence for correlation, depending on the mineralogy, between the Mn and Fe grades of the ore and the final concentrate grade and Mn/Fe ratio. To yield a concentrate suitable for use in ferromanganese production, it is recommended that the ore contain a minimum initial concentration of ～25% Mn and ～10% Fe.     

烧结矿碱度对综合炉料交互反应的影响

以不同碱度的烧结矿及烧结矿与块矿的混合矿为研究对象,利用荷重软化熔滴装置,考察了烧结矿碱度对综合炉料软熔性能及不同炉料间交互作用的影响。研究发现:随着烧结矿碱度增加,炉料结构中块矿的质量配加比例提高,炉料间的交互作用增强,主要表现为综合炉料软化开始温度及熔融开始温度降低,混合炉料的透气性得到改善。炉料结构的变化使矿物间的交互反应随着烧结矿碱度的提高而增强,进而导致液相成分发生改变,降低了初渣物相熔点,而烧结矿碱度过高时会恶化料柱的透气性。同时通过扫描电子显微镜?能量色散谱仪(SEM?EDS)及X射线衍射(XRD)精修表征整个还原过程烧结矿物相变化,渣相中主要物相为浮氏体和硅酸钙,随着烧结矿碱度增加,在不同断点2CaO·SiO₂的含量呈现降低趋势,表明烧结矿还原过程生成的高熔点物相随之降低,综合炉料的液相生成温度随之降低,炉料间交互作用增强。因此,适当提高烧结矿碱度,提高块矿入炉的质量配比,利于高炉的强化冶炼。      

转炉锰矿熔融还原工业试验研究

为打通转炉炼钢过程锰矿熔融还原技术路径,提高锰的收得率,对锰矿熔融还原过程和提高锰收得率的工艺参数进行了热力学探讨,并在某钢厂200 t转炉上开展了工业试验研究。研究结果表明:高效稳定的铁水“三脱”预处理技术是锰矿熔融还原技术成功的基本前提;通过理论计算,在炉渣中的(MnO)质量分数为5%～10%,终点[C]质量分数控制在0.13%～0.36%时,终点钢液[Mn]质量分数可控制在0.3%以上。工业试验主要通过采用双渣法冶炼操作,在确保前期铁水低磷的条件下尽可能控制少渣量、降低炉渣中氧化铁,从而实现加入锰矿后提高锰收得率;并在现有工艺控制条件下,锰矿加入10 kg·t?1以内时,工业试验可使锰矿还原过程锰收得率超过40%,平均为51.40%;为进一步提高锰收得率,建议严格将锰矿熔融还原渣料总量控制在40～60 kg·t?以内,石灰加入量控制在10～15 kg·t?1以内;研究结果为锰矿熔融还原技术的开发和应用提供重要参考。      

Improved manganese extraction in the production of manganese ferroalloys

In the production of manganese ferroalloys from ore, about 50% of the manganese in the ore is lost. The manganese lost with the enrichment-slag tailings may be returned to the production of manganese ferroalloys by dithionate method of enrichment of the slurries. A technology is developed for the production of high-carbon ferromanganese from concentrate obtained by the chemical enrichment of tailings slurries. Low-phosphorus Mn slag is used in the production of ferrosilicomanganese and refined manganese ferroalloys. A method is described for alloying hot metal with manganese from slag during the production of lowand medium-carbon ferromanganese. Processes are developed for the production of medium-carbon ferromanganese by mixing ore–limestone melt with high-carbon ferromanganese and removing the phosphorus from Mn-bearing melts by bubbling with CO. The degree of phosphorus removal (70–90%) depends on the bubbling time. By means of improved production of manganese ferroalloys and extraction of manganese from slag and slurries, the manganese extraction may be significantly increased.     

熔融制样-X射线荧光光谱法测定硅锰合金和锰铁合金中硅锰磷铁

熔融制样-X射线荧光光谱法测定铁合金化学成分,关键技术是样品预氧化,以有效避免铂金坩埚受到侵蚀。试验以专用氧化剂预处理硅锰合金和锰铁合金样品,以四硼酸锂-混合熔剂(m(Li₂B₄O₇)∶m(LiBO₂)=67∶33)为熔剂熔融制备玻璃片,建立X射线荧光光谱法(XRF)测定硅锰合金和锰铁合金中硅、锰、磷、铁含量的方法。以碳含量校正烧失量对检测结果的影响,进一步探讨了氧化剂加入量、稀释比、熔融温度、熔融时间等条件对硅锰合金和锰铁合金中锰、硅、磷、铁含量的影响,得出最佳熔融条件。熔融制得的玻璃片均匀、光洁,满足XRF测定要求。各元素测定结果的相对标准偏差(RSD,n=12)在0.25%~4.3%之间;测定结果与硅锰、锰铁标准物质认定值相符。     

Study of the High Temperature Metallurgical Properties of On-Site Samples with Vanadium–Titanium Magnetite

In China, two typical vanadium–titanium magnetite ores were used as raw materials in iron making. In order to obtain the differences in the high temperature metallurgical properties of these ores, the phase and microstructure of on-site sinter, pellet, slag and laboratorial non-dripped slag were analyzed by XRD and SEM–EDS. The results show that the phases of two typical sinter and pellet have no significant changes, but the microstructures are different. The softening start temperature and softening zone of high chromium vanadium–titanium magnetite (HCVTM) burden are higher than ordinary vanadium–titanium magnetite (VTM) burden. The melting start temperature of HCVTM burden is higher and melting–dripping zone is smaller than VTM burden, which is beneficial to the blast furnace smelting. In addition, the calculation results using Factsage 7.0 are in accord with the experimental results. The primary crystal field of slag of HCVTM is the melilite, and the liquidus temperature is 1409.81 °C; the primary crystal field of slag of VTM is CaTiO₃, and the liquidus temperature is 1418.51 °C.