高硫高铁铝土矿脱硫除铁研究进展

铝是人们现代生活中重要的金属材料,铝土矿是生成铝的主要原料,随着国内铝工业的持续发展,铝土矿资源的需求量在逐年增加。但国内铝土矿资源品质较差、供给不足,铝土矿对外依存度较高,给我国的铝资源供应安全带来严重的威胁,并制约了我国铝工业的可持续性发展。面对我国优质铝土矿资源短缺的问题,开发复杂难选的高硫高铁铝土矿资源,有助于保障我国铝土矿资源战略安全。我国高硫高铁等复杂铝土矿资源量大,约15亿吨以上,并伴生其他战略金属资源,目前亟待高效开发,利用先进工艺可实现此类典型贫杂铝土矿工业化应用。铝土矿中过多的硫杂质和铁杂质会对拜耳法提铝工艺产生不可忽视的影响,如腐蚀设备和管道、增加碱耗和赤泥量、影响氧化铝的质量等。因此,本文从我国高硫高铁铝土矿资源现状及特点入手,综述了高硫高铁铝土矿脱硫除铁工艺的现阶段研究进展,总结了浮选脱硫、预焙烧脱硫、生物法脱硫、湿法脱硫等主要脱硫技术及物理法除铁、化学法除铁、生物法除铁等主要除铁技术,探讨了各种工艺的工业化应用水平并列举了几个典型高硫高铁铝土矿工业化应用实例。将为我国开发利用复杂铝土矿资源提供理论支撑,使难利用铝资源得到有效利用,降低我国对国外铝资源的依赖水平,提高铝土矿资源的保障力。     

山东低铝硅比铝土矿降铁脱硅试验研究

以山东某低铝硅比铝土矿为研究对象,为了实现其降铁、降硅的目的,采用磁选和浮选联合工艺流程,获得较好的工艺指标。原矿铝硅比3.18,在磨矿细度-0.074mm 94.55%的条件下,采用"弱磁-强磁-浮选"工艺流程,弱磁场强度1.2×105 A/m,强磁场强度9.6×105 A/m,以碳酸钠为调整剂,用量3 500g/t,六偏磷酸钠为抑制剂,用量40g/t,油酸钠为捕收剂,用量1 200g/t,最终获得精矿产品铝硅比为9.04,铝品位为62.47%,回收率为62.74%。     

某高铁钾长石矿除铁试验研究

某钾长石矿属高铁难选钾长石矿,通过探索试验(包括干式强磁试验、磁选尾矿浮选试验),对比不同选矿工艺的除铁效果,确定采用浮选工艺.通过浮选条件试验,选定了最佳的浮选工艺条件,长石产品Fe2 O3含量为0.20%,达到了工业应用的要求.     

Processing of gold ores using Guinean bauxite waste

This paper describes the treatment of gold ores via the bauxite waste mud used as a pH modifier in the cyanidation of gold. The red mud is irrefutable in modifying the pH of gold ore sludges. So any gold contained in the red mud is concentrated by gravity separation and is recovered along with gold from the gold ore. Carbon tests are carried out on cyanide leach solutions to determine the level of deactivation resulted by organics in the bauxite waste mud.     

氧化铜钴矿酸浸液深度除铁工艺的研究

以氧化铜钴矿为原料,先通过焙烧预处理、高压酸浸的方法获得含钴浸出液,然后用过氧化氢作氧化剂,考查搅拌时间、溶液温度及沉淀终点pH值等对沉淀除铁的影响.结果表明:浸出液中加入适量过氧化氢溶液作氧化剂,可促进杂质铁的沉淀分离.在溶液温度为60℃、搅拌时间为120 min、沉淀终点pH值为3.5的条件下,杂质铁的去除率可达99.42％,以渣含钴计钴损失率为0.08％,较好地实现了含钴浸出液深度除铁目标.     

铝土矿酸性浸出液中铝、铁的回收

以铝土矿酸性浸出液为原料,通过化学沉淀、碱溶、碳分、煅烧等得到氧化铁和氧化铝粉体。考察了沉淀、碱溶、碳分过程中溶液终点pH值、反应温度、反应时间等参数的影响,得到优化工艺条件。结果表明,在终点pH值5.0、反应温度80℃、沉淀时间50min条件下进行沉淀,铝铁的沉淀率均达99%;在溶液终点pH值14、碱溶温度80℃、碱溶时间30min条件下,铝的溶出率可达99.42%,铁的去除率可达99.63%;在溶液终点pH值9.0、碳分温度40℃、CO2流速选择6mL/min条件下,铝的沉淀率可达98.69%。     

Technology of recovery of associated gold from Siberian iron ores

Conclusions  

关于铁矿石优化利用的探讨

结合国内、国外两种铁矿资源的特点，生产使用状况，对合理利用我国南方地区低铁高硅、高铝铁矿石资源进行了分析讨论。     

A non-invasive technique for sorting of alumina-rich iron ores

This paper describes an Infrared (IR) thermography based technique for sorting of iron ores consisting of alumina-rich particles of relatively low thermal absorptivity as compared to iron-rich particles in the ores. The technique primarily consists of selection of iron ores with Fe compositions ranging from 59 to 69 wt.% and alumina (Al₂O₃) from 0.35 to 8.85 wt.%, crushing the ores up to the particle size range around 10 mm. The iron ore fines are uniformly heated using heat source of wavelength ranging from 10⁻² to 10⁻⁶ m for a period of time sufficient to create a difference in infrared emission between the ore particles. The thermal image of the heated ores is captured by IR thermography. The alumina-rich iron ore particles are heated up less as the thermal absorptivity of these ores is less than the ores with high iron content. Thus, the alumina-rich iron ore particles can be identified by observing the temperature profile and/or thermal image of these ores. This technique of ore recognition can be useful in improving the feed quality of iron ore to the blast furnace in iron and steel industries by rejecting the alumina-rich ores through modification in the presently existing processes.     

铝土矿中铝、铁和硅有价组分的综合利用研究

针对山东某地铝土矿高铝、高铁、高硅、低铝硅比的特点,设计了一个综合利用矿石中铝、铁、硅的工艺流程。通过硫酸铵焙烧、水浸、过滤,矿石中的铝、铁等有价组元进入浸出液中,二氧化硅在渣中富集。利用不同金属离子的溶度积的差别,通过加入沉淀剂碳酸铵调节溶液pH值,滤液中的铁和铝分别以氢氧化铁和氢氧化铝的形式析出,再经高温煅烧得氧化铁和氧化铝粉体。氧化铁的回收率可达85%以上,氧化铝的回收率可达95%以上。硫酸铵低温焙烧铝土矿的工艺实现了铝、铁和硅的综合利用,整个流程无废物、废水和废气的排放。     

Direct extraction of nickel and iron from laterite ores using the carbonyl process

The carbonyl method of refining nickel and iron was invented more than 100 years ago and has been used for refining of nickel commercially. CVMR® developed the process of direct extraction of nickel and iron from laterite ores as metal carbonyls which in turn produced pure nickel and iron metals.CVMR®’s carbonyl technology has been applied to several types of limonite and saprolite ores containing other metals such as copper, cobalt and PGE. The process consists of reducing the ore with hydrogen, extracting of iron and nickel in the form of volatile metal carbonyls, separating the metal carbonyls and producing high purity nickel and iron metals; and production of copper, cobalt and PGE concentrate by gravity or magnetic separation. Economic evaluation of this process shows significant increase in cash flow. The CVMR® process does not produce liquid waste and does not require tailing dumps. This makes CVMR®’s process attractive for projects in areas that are environmentally sensitive, or have a high level of rainfall.     

The use of diffuse reflectance spectroscopy for the characterization of iron ores

The aim of this work was to develop a diffuse reflectance methodology for quantifying minerals in powdered iron ores, which is a key quality control requirement for these materials. Selected samples ranging widely in their concentrations of hematite (as specularite and martite), goethite, magnetite, and quartz were collected in mines from the Iron Quadrangle, Minas Gerais State, and also in the Carajás region, Pará State, Brazil. A chemometric analysis based on the concentrations of the different minerals as determined with a combination of conventional methods (chemical analysis, X-ray diffraction, Mössbauer spectroscopy, light-reflected microscopy, and magnetic susceptibility) and the principal components derived from the diffuse reflectance spectra in the visible range was performed. Principal component regression analysis provided successful calibration for the concentrations of goethite (r² = 0.94; standard error of validation (SEv) = 4.2%) and hematite (r² = 0.89; SEv = 7.4%), in addition to good estimates for quartz (r² = 0.83; SEv = 7.4%), specularite (r² = 0.80; SEv = 11.6%), and martite (r² = 0.78; SEv = 10.6%). Our results suggest that diffuse reflectance spectroscopy is a promising tool for the simultaneous determination of minerals in iron ores within a few minutes only.     

ZVI-SRB协同处理铀废水的正交实验研究

在缺氧的环境下,利用零价铁(ZVI)和硫酸盐还原菌(SRB)协同处理含铀废水,通过正交实验考了察初始pH,铀的初始浓度,SO42-,NO3-对ZVI-SRB协同处理含铀废水的影响.结果表明,铀的初始浓度对ZVI-SRB协同处理铀废水的影响最大,其次是NO3-,pH值,SO42-;在500mL的水样中,其最佳的还原条件是:pH为5,SO42-为3000mg/L,NO3-为400mg/L,铀的初始浓度为160mg/L;在最佳还原条件下,铀的去除率为93.49%.     

二聚酸副产物单体酸对鞍山式赤铁矿浮选试验研究

为了提高二聚酸副产物单体酸的价值,分析了单体酸成分,主要含有饱和、不饱和和异构脂肪酸。采用尿素包合法获得含量较高的异构脂肪酸,分别与原料、油酸复配后构成了一系列捕收剂,并用于鞍山齐大山铁矿石浮选试验。通过实验室开路和闭路浮选试验结果表明:浮选温度为25℃时,精矿铁品位66.38%,尾矿铁品位14.90%,铁回收率84.19%。与KS-Ⅱ浮选药剂相比,在降尾、铁回收率和降低药剂用量方面有优势。     

广西某高硫高铁铝土矿拜耳法溶出试验研究

针对广西某地高硫高铁一水硬铝石型铝土矿的矿石特性,采用浮选脱硫-拜耳法溶出工艺流程,对其进行反浮选除硫再进行拜耳法溶出试验。结果表明,该高硫高铁铝土矿可通过浮选方法脱硫,脱硫尾矿进行拜耳法溶出可以得到较佳的溶出效果。其较佳的溶出条件为溶出温度260℃、溶出时间45 min、配料分子比1.4、石灰加入量10%、循环母液苛性碱浓度260 g/L,在此条件下氧化铝的相对溶出率达到99.40%。     

Magnetic separation of hematite and limonite fines as hydrophobic flocs from iron ores

Magnetic separation of weakly magnetic iron mineral fines in the form of flocs, which is termed Floc Magnetic Separation (FMS) process, has been studied in the present work, in order to find a substitution for high-intensity or high-gradient magnetic separators to treat the ores with weakly magnetic iron minerals in the fine size range. This study was performed on a hematite ore and a limonite ore that were finely ground to be micron particles, through the hydrophobic flocculation induced by sodium oleate and kerosene to make flocs. The experimental results have shown that the FMS process is effective to recover hematite and limonite fines at a middle magnetic field intensity, greatly increased the separation efficiency, compared with the conventional magnetic separation at the same conditions. By applying the process to the fine hematite ore containing 30.5% Fe, a concentrate assaying 64% Fe with 82% recovery has been produced. It has been found that the separation efficiency of the FMS process closely correlates with the main parameters of hydrophobic flocculation such as sodium oleate addition, conditioning time and kerosene addition. This finding suggests that the high efficiency achieved by the FMS process might be attributed to the considerable increase of the magnetic force on the iron mineral fines in the form of hydrophobic flocs in a magnetic field, thus the fines can be held by the separation plates in a magnetic separator and then be collected as magnetic concentrates.     

Biomining in reverse gear: Using bacteria to extract metals from oxidised ores

Biomining, as traditionally practised, uses aerobic, acidophilic microorganisms to accelerate the oxidative dissolution of sulfide minerals present in ores and concentrates, thereby either causing target metals to be solubilised (e.g. copper) or made accessible to chemical extraction (e.g. gold). Many acidophiles are also able to catalyse the dissimilatory reduction of ferric iron in anoxic or oxygen-depleted environments, and can accelerate the reductive dissolution of ferric iron minerals, such as goethite, under such conditions. Recent work has demonstrated how this approach can be used to extract metals (nickel, copper, cobalt and manganese) from oxidised ores, such as laterites deposits, at low (∼30 °C) temperatures. Reductive mineral dissolution has been trialled successfully with a variety of ores, pointing to a generic application of this approach.