A two-stage thermal upgrading process for nickeliferous limonitic laterite ores

Sulphide ore deposits are becoming increasingly less viable as a source of nickel, driving recent interest in the development of nickel laterite deposits. The difficulties with the current methods of nickel metal production from these oxide ores arise mainly from the inability to produce a concentrate analogous to that obtained in the flotation of sulphide ores, resulting in high production costs. In this work, a two-stage reduction and thermal growth process is proposed for the treatment of the nickeliferous limonitic laterite ores to produce a ferronickel product, recoverable by magnetic separation. An initial reduction roast of the ore with 6% coal and 4% sulphur additions at 600°C for 1?h, followed by particle growth for 1?h at 1000°C, produced a ferronickel concentrate with a nickel grade of 4% and a nickel recovery of 93·2%. The impact of particle growth temperature and retention time at temperature on the ferronickel particle size was also studied. For the control conditions, typical ferronickel particles produced were 10–20?μm in size. The particle size did not significantly change at temperatures higher than 1200°C or for retention times beyond 60?min.     

Leaching characteristics of nickeliferous pyrrhotite tailings from the Sudbury,Ontario area

Mineralogical characterisation showed the deportment of Ni to be similar in the Vale and Glencore tailings, with 60% of the total Ni locked in pyrrhotite, and the balance 40% associated with pentlandite. Nickel leaching was correlated with the dissolution extents of pyrrhotite and pentlandite as functions of four leaching regimes: ‘anoxic acid’ (with and without pH control), ‘oxic acid’ (oxygen sparging), ‘oxic acid’ (air sparging), and ‘oxic ferric’ (air sparging). The results showed that the maximum Ni dissolution was obtained during the pH controlled oxic acid leach with oxygen sparging at pH 1.5, while the anoxic acid leach at pH 1.5 resulted in minimum Ni dissolution (10–15%) from pyrrhotite. An overall Ni mass balance showed that pyrrhotite and pentlandite dissolve simultaneously in the presence of Fe(III) and oxygen, in contrast to the preferential dissolution of pyrrhotite in the absence of Fe(III). Elemental sulphur yield increased with increasing temperature, but no observable trend could be linked to ferric or ferrous ion concentration.     

Recovery of nickel and copper from high-grade matte at Impala Platinum by the Sherritt process

High-grade nickel-copper matte is treated at Impala Platinum to produce nickel briquettes and copper cathodes. The remaining residue is separately treated for the recovery of platinum group metals. The major portion of the nickel values is preferentially extracted in a first stage acid oxidation leach. The resulting nickel solution contains little or no dissolved copper. After adjustment with recycled ammonium sulphate and ammonia, this solution is reduced directly with hydrogen under pressure, to produce a nickel powder product which is subsequently briquetted and sold as such. Second stage acid oxidation leach is carried out on the first stage leach residue to extract substantially all of the copper values as well as the residual nickel values. Copper is recovered from the solution in an electrowinning step and the spent electrolyte containing copper, nickel and sulphuric acid is recycled to the first stage leach. The second stage residue is further leached under acid conditions to provide a final residue rich in platinum group metals. This residue constitutes the feed to the Impala platinum metals refinery.     

锰硅合金炉渣中锰回收率的影响因素

根据电炉冶炼锰硅合金的实际生产经验,分析了锰硅合金生产过程中影响锰硅合金炉渣含锰量的主要因素。同时指出,只要把这些主要因素控制在合适的范围内,就可降低渣中的含锰量,提高锰的回收率。     

红土镍矿直接还原焙烧磁选回收铁镍

采用添加助熔剂直接还原焙烧-磁选方法,对镍主要以硅酸镍形式存在的低品位红土镍矿中镍和铁的富集进行了研究.结果表明,同时添加助熔剂,可获得较好的技术指标.最佳工艺条件为:煤作还原剂,质量分数为15%;KD-2为助熔剂,质量分数为20%;焙烧温度为1200℃;焙烧时间为40min.在此条件下可以得到镍品位10.83%、铁品位52.87%、镍回收率82.15%和铁回收率54.59%的镍铁精矿.用X射线衍射(XRD)和透射电镜(TEM)对还原过程中助熔剂和煤的作用机理进行了研究.发现KD-2可以与原矿中含镍的石英和硅酸盐矿物反应,释放出其中的镍;煤用量太多时可生成部分不含镍的金属铁,会造成镍的回收率降低.     

熔融氯化挥发工艺处理凡口窑渣综合回收有价金属的研究

采用熔融氯化挥发工艺综合回收凡口窑渣中的有价元素,考察了反应时间和氯化剂种类对有价金属挥发率的影响。结果表明:控制反应时间超过30min,以氯化钠作氯化剂,锗和铅的挥发率在90%以上,银挥发率超过80%,锌和铜的挥发率偏低(60%～70%)。该工艺具有自热、烟尘中有价元素富集比高等优点。     

120 t转炉出钢利用LF固态精炼渣进行渣洗的工艺实践

120 t转炉冶炼低碳铝镇静钢SPHC的出钢过程中向底吹氩的钢包中加2.0~2.5 kg/t铝铁(49%Al),并加入2.5~4.0 kg/t LF精炼固态弃渣(/%:6.29~10.33SiO₂,19.14~29.51 Al₂O₃,54.69~59.96CAO,4.97~6.89MgO)以替代钢水净化剂(预熔渣-钢渣改质剂/%:10~18Al₂O₃,42~55CaO,＞3.5Al,2~5MgO,6~10CaF₂)的生产结果表明,LF精炼弃渣,化渣迅速,有利于吸附夹杂物,降低T[O],消除水口结瘤,有利于改善环境和降低成本。     

Recovery of nickel from Orimulsion fly ash by iminodiacetic acid chelating resin

Macroporous resins containing imminodiacetic acid (IDA) groups (Lewatit TP-207, Purolite S-930 and Amberlite IRC-748) were studied under dynamic conditions for uptake of nickel ions from the sulphate solution at pH 4 deriving from preliminary acid leaching of Orimulsion fly ash and subsequent vanadium recovery and impurities removal stages. The effects of temperature and ionic medium on the Ni adsorption were investigated.     

70 t电弧炉热兑转炉液态渣的工艺实践

转炉液态渣的碱度(CaO/SiO₂)一般为2.8～4.2,热容2.5 kJ/(kg·℃),进入渣罐后的炉渣温度约为1 540℃,有良好的导电性,可以利用其热能和氧化钙。当70 t电弧炉兑加120 t转炉液态渣8 t,可使平均冶炼周期由52 min降至47 min,电耗由400 kWh/t降至355 kWh/t,石灰加入量由3.6 t降至1.0 t,氧气消耗由28 m~3/t降至25 m~3/t,可有效地节约资源和减少炉渣的排放。     

The mineralogy of pyrrhotite from Sudbury CCN and Phoenix nickel ores and its effect on flotation performance

Abstract

The non‐stoichiometric sulphide pyrrhotite (Fe_1?xS), common to many nickel ores, occurs in a variety of crystallographic forms and compositions. In order to manipulate its performance in nickel processing operations either to target the recovery or rejection or pyrrhotite, one needs an understanding of pyrrhotite mineralogy, reactivity and the effect this may have on its flotation performance. In this study, a non‐magnetic Fe₉S₁₀ pyrrhotite from Sudbury CCN in Canada and a magnetic Fe₇S₈ pyrrhotite from Phoenix in Botswana were selected to explore the relationship between mineralogy, reactivity and microflotation. Non‐magnetic Sudbury pyrrhotite was less reactive in terms of its oxygen uptake and showed the best collectorless flotation recovery. Magnetic Phoenix pyrrhotite was more reactive and showed poor collectorless flotation, which was significantly improved with the addition of xanthate and copper activation. These differences in reactivity and flotation performance are interpreted to be a result of the pyrrhotite mineralogy, the implications of which may aid in the manipulation of flotation performance.

La pyrrhotine sulfureuse non stoechiométrique (Fe_1?xS), commune à plusieurs minerais de nickel, se retrouve sous une variété de formes cristallographiques et de compositions. Afin de manipuler son rendement lors des opérations de traitement du nickel, soit afin de viser la récupération ou bien la rejection de la pyrrhotine, on a besoin de comprendre la minéralogie de la pyrrhotine, sa réactivité et leur effet sur le rendement de sa flottation. Dans cette étude, on a choisi une pyrrhotine non magnétique, Fe₉S₁₀, de Sudbury CCN au Canada et une pyrrhotine magnétique, Fe₇S₈, de Phoenix au Botswana, pour explorer la relation entre la minéralogie, la réactivité et la microflottation. La pyrrhotine non magnétique de Sudbury était moins réactive par rapport à son absorption d'oxygène et a montré la meilleure récupération par flottation sans collecteur. La pyrrhotine magnétique de Phoenix était plus réactive et a montré une mauvaise flottation sans collecteur, que l'on a améliorée significativement avec l'addition de xanthate et l'activation au cuivre. Ces différences de réactivité et de rendement de la flottation sont interprétées comme étant un résultat de la minéralogie de la pyrrhotine, dont les implications peuvent aider à manipuler le rendement de la flottation.     

高锰含钴物料中钴的回收

采用矿浆电解工艺处理高锰含钴物料,可以使物料中的大部分锰以MnO2的形态在阳极析出。较常规处理工艺,所得到的含钴溶液中的钴锰比可以由1∶3升高至4∶3,需净化处理的锰金属量降低3/4,每吨Co的试剂消耗费用可以降低1万元以上。     

Dynamic modelling of an industrial copper solvent extraction process

The dynamic behaviour of an industrial copper solvent extraction mixer–settler cascade is modelled to develop an advanced process control system. First, the process is introduced and the dynamical models are formulated. The testing environment is described and the successful results presented. Only industrially measured variables are required and plant-specific McCabe-Thiele diagrams are utilized to predict copper concentrations. The results with constant and adapted parameters are compared and the importance of parameter adaptation is discussed. Testing the simulator with adapted parameters over a period of 1 month of industrial operating data gave data that followed the real process measurements closely. In the future, the mechanistic models will be used for control system development and testing. The model can be used on all copper solvent extraction plants by modifying the flow configuration and adapting parameters.     

响应曲面法优化红土镍矿富集镍

摘要：为了从源头实现铁矿烧结NOx减排,采用燃料燃烧及烧结杯实验,使用烧结用生石灰改性燃料,研究生石灰改性用量（生石灰与燃料质量比）对燃料燃烧过程N转化率和NOx排放量（每克燃料燃烧排放NOx的质量）的影响。结果表明,在0～3.0%（质量分数）的范围内,随着生石灰改性用量提高,燃料燃烧N转化率及NOx排放量降低,烧结过程NOx平均浓度降低。当生石灰改性用量超过3.0%(质量分数)时,NOx减排效率有所降低。结合烧结指标综合考虑,适宜生石灰改性用量为1.0%～3.0%。     

Recovery of cobalt, nickel, and copper from sea nodules by their extraction with alkylphosphines

The paper describes a process for the recovery of pure Co(II), Ni(II), and Cu(II) from a hydrochloric acid solution of polymetallic sea nodules. An overnight contact of the nodule powder with 4 M HCl almost quantitatively leaches these metal ions. From the leachate, Co(II) and Cu(II) were recovered by their extraction with Cyanex 923 and Ni(II) by extraction with Cyanex 301. Co(II) and Cu(II) are partitioned in the organic phase as H₂CoCl₄·2 Cyanex 923 and CuCl₂·2 Cyanex 923, whereas Ni(II) is extracted in the form of NiR₂ (HR=Cyanex 301). A solution of 0.001 M H₂SO₄ is used for the stripping of Co(II) and Cu(II) and 5% NH₄Cl in 75% NH₃ for Ni(II). Both extractants are found to be stable toward prolonged contact with HCl and show negligible loss in their extraction capacity even after recycling them for 20 cycles. The partition data have been utilized in developing conditions for the separation of Co(II), Ni(II), and Cu(II) mutually and from other metal ions, namely Ti(IV), Al(III), Fe(III), Mn(II), and Zn(II). The procedure of separation thus developed has been extended for the recovery of around 90% Co(II), Ni(II), and Cu(II) from sea nodules. The purity of the metal ions thus obtained is around 99%.     

钒钛磁铁矿深度直接还原熔分提铁

以热力学分析为基础,采用直接还原熔分工艺对国外某钒钛磁铁矿进行了研究.利用 Factsage 软件计算了不同添加剂配比下的渣相四元相图,并进行直接还原试验,研究了 SiO2和 CaO 加入量对还原反应的影响以及CaF2的加入量对铁品位和回收率的影响.结果表明：在还原温度1380℃,还原时间30 min,SiO2的质量分数为7.0％,CaO的质量分数为3.5％,CaF2的质量分数为1.4％,煤粉加入质量分数为17.4％的实验条件下,还原后金属相中铁品位在95.0％以上,铁回收率97.0％以上.     

EAF Smelting Trials of Waste‐Carbon Briquettes at Avesta Works of Outokumpu Stainless AB for Recycling Oily Mill Scale Sludge from Stainless Steel Production

The EAF steel plant of Avesta Works, Outokumpu Stainless AB, has been used to perform smelting reduction trials of briquettes consisting of oily mill scale sludge, carbon and other wastes. A total of 7 briquette smelting trials were performed. The heats were processed smoothly smelting 3 t of briquettes or 3.4 mass‐% of metal charges. The quantities of FeSi powder and O₂ gas injected and electric energy supplied were increased to smelt briquettes of 6 t. No impacts were found on the analyses of the crude stainless steel tapped from the EAF during the trials. The results of the briquette smelting have been evaluated by referring to the data from the reference heats and results from earlier laboratory tests. The recovery of Cr, Ni and Fe elements from the briquettes was nearly complete and was found to occur mainly through carbon reduction. The slag masses were not increased in three trials as compared with the reference heats. There were moderate increases in the slag masses in four trial heats. The increases were, nevertheless, lower by 52‐69% than the slag masses generated by Sireduction of the briquette oxides. Afterwards, by referring results from the present trials, waste‐carbon briquettes amounting to 1‐3 t were smelted very smoothly in many of the EAF heats at Avesta Works to recycle the oily mill scale sludge and other wastes from stainless steel production.     

浅析高冰镍氯气浸出制取镍电解初液

氯气浸出工艺是当前世界上先进的高镍锍精炼工艺之一,在镍的回收率、生产率、产品质量及工作环境等方面具有较突出的优势.氯化湿法冶金由于具有高反应速率、高浸出率、以及灵活的金属提取工艺组合等优点,成为一项重要的湿法冶金新技术,以往制备镍电解初液的工艺都采用硫酸常压选择性浸出-加压浸出工艺,这样的工艺具有浸出效率低、工艺设备复杂、流程长、作业强度高、生产成本高等缺点.为了解决这些不利的因素,现在学者都在探索氯化浸出工艺替代硫酸选择性浸出工艺.本文就氯气浸出生产镍电解初液的工艺原理、试验过程、试验结果及其优点进行了充分的阐述.     

90 t钢包炉底吹氩工艺优化的水模拟试验研究

采用1:2.5几何相似比的水模型,试验研究了钢厂90 t钢包炉(LF)透气砖位置、数量和底吹供气量对钢包内流体混匀时间的影响。结果表明,优化后的钢包透气砖位于高位料仓下料位置的下方,渣料和合金能够直接加在裸露区,熔化速度快,合金收得率高;底吹气体流量23.89 L/min时钢包流体混匀时间最短,有利于钢水深脱硫。     

红土镍矿选择性还原-熔分制备镍铁合金

以硅镁型红土镍矿为原料,采用金属化焙烧-熔分工艺,通过正交试验制备金属化球团,将所得金属化球团在1500℃条件下熔融分离30 min提取镍铁合金,考察影响因素对实验结果的影响.结果表明：在选择性还原制备金属化球团过程中,对金属化率的影响程度从大到小的因素依次是C/O摩尔比、焙烧温度、焙烧时间和碱度;实验可获得镍品位19%的镍铁合金;在碱度为0.8-1.2范围内,S和P分配比随着碱度的升高而增大.利用X射线衍射和扫描电镜对金属化球团及熔融分离出的渣进行微观分析,发现加入的石灰石与复杂矿相反应可释放出简单镍氧化物和铁氧化物,促进还原反应的进行,当石灰石不足时,少量铁以Fe³⁺的形式存在于铁金属化率70%的金属化球团中.