Australian Ore Research Articles

Characterization of dust emission during ore unloading and analysis of its influencing factors

Dry bulk terminals at ports generate dust in the process of ore loading / unloading and transfer, and these particulate matters disperse to the atmospheric environment causing pollution and endangering human health. This study focuses on the funnel unloading point of a portal crane at a port terminal, and the variation characteristics of dust emission under different mass flow rates, ambient wind speeds, and moisture contents are investigated. The microscopic features of ore powders, i.e., wetting time, contact angle, particle size, specific surface area and pore structure, as well as microscopic morphology, are also determined to explore the intrinsic mechanism between wettability, moisture content, and dust emission. The impact of mass flow rate, ambient wind speed, and moisture content on dust emission is evaluated by employing the orthogonal test range method and response surface method. The experimental data reveals that the dust at the unloading point is dominated by coarse particles of total suspended particulate (TSP), and increasing the moisture content effectively reduced the dust emissions, with a suppression efficiency of TSP > PM10 > PM2.5. The experimental results on the microscopic features of the ore powders indicate that the above difference is attributed to wettability, which weakens with diminishing particle diameter. It is also concluded that the wettability of Australian ore 1 is determined to be superior to bauxite 394. Therefore, Australian ore 1 exhibits an excellent dust suppression effect at a moisture content of 4% ∼ 5%, whereas bauxite 394 requires a moisture content of approximately 5% ∼ 7% to achieve the same dust suppression. By conducting the orthogonal test range method, the three factors on the dust emission, in descending order, are moisture content > ambient wind speed > mass flow rate. According to the response surface method, the optimal parameter combination is determined and the dust emission is minimized as 4.149 μg/s, which corresponds to 0.386 mg TSP/ton, with the conditions of mass flow rate 10.356 kg/s, ambient wind speed 4.289 m/s, moisture content 6.983%.

Grinding of Australian and Brazilian Iron Ore Fines for Low-Carbon Production of High-Quality Oxidised Pellets

Oxidised pellets have become an indispensable high-quality charge for blast furnaces. Nevertheless, high-quality pellet feeds are becoming scarcer and scarcer. To broaden the range of sources of pellet feeds and reduce the production cost of pellets, more steel mills are predicted to use coarse iron ore fines with a relatively low iron grade and low impurities for the preparation of desirable pellet feeds through a typical wet grinding–settling–filtering process. In this work, the grinding, settling and filtering behaviour of Brazilian and Australian iron ore fines are studied and compared, with the aim of discovering the internal relationship between the mineralogical characteristics of different iron ore types and their grinding–settling–filtering performance. Additionally, the effects of ore blending on pellet preparation were investigated. The results show that, usually, the higher the hardness of the iron ore, the more grinding energy is required. Australian and Brazilian ore fines exhibit good grindability, with a Bond work index of about 10–15 kW·h/t. Furthermore, ore blending can reduce grinding energy consumption and improve settling and filtration rates, and the addition of finely ground Australian ores improves the balling performance of pellet mixtures. At the same bentonite content, the ball drop strength of the three blends with added Australian ore is significantly higher than that of the base blend, and the fired pellets obtained from Blend 1, Blend 2 and Blend 3 blends exhibit good metallurgical properties.

Life-cycle analysis of battery metal recycling with lithium recovery from a spent lithium-ion battery

Demand for critical materials (nickel, cobalt, manganese [NCM], and lithium) for use in batteries is increasing rapidly due to the expansion of the battery-electric vehicles market. Battery metal recycling (BMR) is an important technology that can potentially realize environmental and economic benefits in cathode active material (LiNixMnyCozO2) production using recycled materials. While current major battery recycling technologies recover cathode materials (NCM) and other metals (steel, aluminum, copper, etc.) from the spent battery, the lithium (Li) recovery rate is less than 1% in the world. In this study, we analyze the environmental benefits of a BMR process that recovers lithium in the form of lithium hydroxide monohydrate (LiOH∙H2O) along with other cathode materials. Using life-cycle analysis (LCA), we evaluate the life-cycle greenhouse gas (GHG) emissions, criteria air pollutant emissions, and water consumption of the new BMR technology in terms of lithium hydroxide production and cathode active material production. The LCA results show that the life-cycle GHG emissions recycled LiOH are 37–72% lower than those of virgin LiOH production from Chilean brine and Australian ore, respectively. In addition, the life-cycle GHG emissions of NCM811 produced using the recycled materials are 40–48% lower compared to virgin cathode active material production. Furthermore, recovering lithium from the spent batteries reduces associated air pollutant emissions and water consumption relative to using the virgin materials or materials from other recycling technologies without LiOH recovery.

Contributing to regional decarbonization: Australia's potential to supply zero-carbon commodities to the Asia-Pacific

The Asia-Pacific has experienced prodigious growth in energy use and is by far the world's largest greenhouse-gas emitting region. Australia has played a leading role in meeting the region's energy and resource needs, becoming the world's largest exporter of coal, liquefied natural gas, iron ore, and alumina. Our analysis shows that these exports are tied to sizeable consequential emissions at the point of use or processing, accounting for about 8.6% of the total greenhouse gas emissions of the Asia-Pacific. The paper investigates three pathways by which Australia could instead export zero-carbon energy and products: direct exports of renewable electricity via sub-sea cables, exports of zero-carbon fuels such as green hydrogen, and the export of “green” metals processed from Australian ores using renewable energy. Carrying out robust, high-level calculations we find that Australia has the land and renewable energy resources to become a key exporter of these commodities. Realization of this potential relies on ongoing cost reductions, growing demand-side interest linked to meeting ambitious emission reduction targets in the region, and the development of cross-border frameworks for clean energy trade. If it were to achieve this goal, Australia could make a sizeable contribution to regional decarbonization via renewable-energy based exports.

Influence of iron ore concentrate on the characteristics of sintering and reduction of sinter

As Australia is the main iron ore importing country for China, the abundant mineral resources of Australia are the primary raw materials for the sintering process. To better understand the properties of different iron ores from Australia and then guide the sintering process, this study selected four types of Australian ore and one type of domestic ore, and their properties were investigated under different conditions. The experiment of single iron ore sintering was studied to examine the influence of different iron ores on the metallurgical properties of sinter. From this study, the following results were obtained: GG showed poor fluidity and higher assimilability temperature, but the bonding phase strength was the highest; YD showed better fluidity and lower assimilability temperature, whereas SJY (domestic ore) showed better fluidity and higher bonding phase strength, and lower assimilability temperature. The influence mechanism of iron ore on the fluidity was further analyzed by using SEM and ion theory of slag. With the increase SiO2 content of iron ore, the fluidity index increased, the main reason was that the amount of liquid phase increased and the melting point decreased during the sintering. However, an excessive amount of SiO2 caused the decrease of fluidity index of iron ore; the main reason was that the fluidity of the liquid phase itself decreased and secondary hematite appeared. In the case of the higher SiO2 content of iron ore, the main bonding phase was calcium silicate. With the decrease of SiO2 content, the calcium silicate transformed into calcium ferrite. The main reason for this was that the Gibbs free energy of calcium ferrite and dicalcium ferrite (2CaO?SiO2) was higher than that of calcium silicate in the temperature ranges of 400-1600 K. The reduction degree of YD was the highest in all the cases and that of GG was the lowest. Activation energies of 5.39, 3.14, 3.51, 4.47 and 2.92 kJ/mol were obtained for the reduction of GG, PB, BH, SJY, and YD, respectively. In all the cases, the reaction corresponded to the model function of F1(?), and the integral form was -ln(1-?)=kt. Through this investigation, it could be concluded that the most appropriate ore category for sinter pot was YD.

Geology of Australian ore deposits

The Australian Ore Deposits monograph, published recently by The Australasian Institute of Mining and Metallurgy, has its focus on descriptive summaries of ore deposit geology. These summaries are ...

Australian Ore Deposits. Sixth Edition (N. Phillips, ed.)

Australian Ore Deposits. Sixth Edition (N. Phillips, ed.)

A study of flotation characteristics of monazite, hematite, and quartz using anionic collectors

Rare earth element (REE) minerals found in most South Australian ore deposits are in complex association with gangue minerals, typically hematite and quartz. Monazite, a phosphate mineral containing mainly light REEs, is one of the principal minerals found in South Australian REE-bearing deposits. Froth flotation, which exploits the differences in the physicochemical properties of minerals, has proven to be effective in the beneficiation of REE minerals. The physicochemical properties of monazite, hematite, and quartz including zeta potential, contact angle, and floatability were determined in this investigation. Sodium oleate, sodium dodecyl sulphate, and hydroxamic acid were employed as collectors. Electroacoustic zeta potential measurements were used to identify the interaction between monazite, hematite, and quartz and the selected collectors. The capillary rise method was used to determine the contact angle of the three minerals. Single mineral flotation using Denver microflotation cell was carried out to confirm physicochemical properties measured. It is shown that the contact angle of the minerals is dependent on the collector type used. The isoelectric point (IEP) of monazite, hematite, and quartz occurred at pH of 6.5, 6.9, and 2.2, respectively. The zeta potential results also suggest that the collectors chemisorb onto monazite and hematite surfaces with a corresponding change in IEP values. Single mineral flotation results demonstrated that monazite and hematite could be floated by the selected collectors; however, low or no quartz flotation was observed in some cases. Results from electrokinetic and contact angle measurements are consistent with that of the floatability of monazite, hematite, and quartz.

Calculations of manganese ferroalloys production efficiency from different ores

The cost of producing manganese alloys by reduction from manganese ore using carbothermic process is estimated. Alternatives of FeMn78 and SiMn17 production from rich Australian manganese ore with low-phosphorus concentration or low-phosphorus manganese slag in charge mixture with poor domestic Russian ore with comparatively high phosphorus content are calculated and presented in the article. Direct production costs for alternative variants in a wide range of cherge composition are estimated.

Ore blending ratio optimisation for sintering based on iron ore properties and cost

The iron ore blend for sintering depends to a great extent on ore properties. It is hard to determine the final sinter reducibility from the reducibility and ratio of single iron ores in a mixture. For production cost reduction, optimised blending ratios were designed according to ore prices and properties (microstructure, crystal water decomposition, assimilation ability, liquid phase fluidity), ensuring nearly identical chemical composition as the mixture used in actual sintering. Sinter pot tests were conducted to determine the optimum mix. The results indicate that properties of iron ores vary greatly, which should be considered for the design of ore blending ratio. The total content of the two Australian ores tested should not exceed 45%. The cost of sintering process could be further reduced together with an improvement of economic and technical indices, only by ratio adjustment of present ores.

Changing Bed Bulk Density and other Process Conditions during Iron Ore Sintering

Iron ore sintering blends in the Asia-Pacific contain significant levels of Australian ores which are lower in bulk density compared to Brazilian ores. This study explores the impact of further decreasing the bulk density of a fairly typical ore blend. This was done by introducing small amounts of a very porous ore into the blend. Measured decreases in bulk density were up to 3%. All the sinter quality parameters could be maintained or improved without the need to increase coke rate. Changes in sinter density results were not significant, indicating that the changes in bed bulk density did not have a significant effect on sinter porosity. The study was then extended to include a comparable blend and two hematite blends of higher bulk density. Decreasing green bed bulk density, bed shrinkage and sinter density did not have a detrimental effect on sinter tumble strength. The associated increase in porosity with the measured changes in sinter density is estimated to be up to 10%. Results showed that sinter density values obtained for the low bulk density mixes at increased coke addition were still lower than equivalent values for the hematite mixes. As expected flame front speed was dependent on post-ignition airflow rate and both these parameters influence sinter strength. Many blends studied have binders and results indicated that their inclusion into sinter mixes gave increased post-ignition airflow values.

국내 비철금속 제련시설에서의 납 동위원소 배출특성 연구

This study was conducted to build up the inventories of Pb isotopic compositions of major Pb pollution sources in South Korea. Since non-ferrous metal smelters are one of major anthropogenic sources, two smelters for zinc, each one of smelter for lead and copper were selected for the study. The Pb concentrations and isotopic compositions of metal ores, wastewater, sludge, metal rod and produced sulfuric acid were analysed to understand the Pb isotopic patterns in environment. The isotopic ratio, , of zinc ores from zinc smelter were in the range of 1.179~1.198 and the ratio of waste, flue gas and products samples were 1.105~1.147. This results implied that the isotopic patterns of output samples showed mixing patterns between two distinct metal ore soerces. In 2011, major importing countries of zinc ore were Australia, Peru and Mexico. Thus Pb isotopic patterns from zinc smelter is originated from the mixing patterns between less radiogenic Australian ores and more radiogenic South America`s ores. Lead smelters also showed the same mixing patterns with those of zinc smelters. However copper smelter showed same Pb isotopic patterns with more radiogenic South America`s ores.

Sintering Properties and Optimal Blending Schemes of Iron Ores

In order to obtain good sintering performance, it is important to understand sintering properties of iron ores. Sintering properties including chemical composition, granulation and high-temperature behaviors of ores from China, Brazil and Australia. Furthermore, several indices were defined to evaluate sintering properties of iron ores. The results show that: for chemical composition, Brazilian ores present high TFe, low SiO2, and low Al2O3 content. For granulation, particle diameter ratio of Brazilian ores are high; particle intermediate fraction of Chinese concentrates are low; and average particle size and clay type index of Australian ores are high. For high-temperature properties, ores from China, Brazil and Australia present different characteristics. Ores from different origins should be mixed together to obtain good high-temperature properties. According to the analysis of each ore's sintering properties, an ore blending scheme (Chinese concentrates 20% + Brazilian ores 40% + Australian ores 40%) was suggested. Moreover, sinter pot test using blending mix was performed, and the results indicated that the ore blending scheme led to good sintering performance and sinter quality.

Historical lead isotope record of a sediment core from the Derwent River (Tasmania, Australia): A multiple source environment

A 105cm sediment core from the Derwent River (Tasmania, Australia) was collected in 2004 and was characterised considering both physical (loss on ignition at 550°C and grain size) and chemical (Fe, Cu, Zn, Cd and Pb concentrations, Pb isotope ratios and 210Pb dating) properties. The core was analysed to (i) investigate the historical profiles of some important elements associated with the Risdon zinc refinery adjacent to the Derwent River, (ii) determine Pb isotopic signatures of sediment samples, and (iii) assess the veracity of Pb isotope ratios as indicators of contaminant Pb input. Extractable metal concentrations were (all values as mgkg−1, non-normalised for grain size) Fe: 20,000–35,000, Zn: 42–4500, Pb: 5–1090, Cu: 13–141, and Cd: 1–31; with a close correlation between Cu, Zn, Cd and Pb. Metal enrichment factors (normalised to Al) were Pb: 0.9–144, Zn: 0.8–93, Cd: 0.8–30, Cu: 0.8–8.9 and Fe: 0.9–1.3, confirming anthropogenic contributions of Cu, Zn, Pb and Cd to the sediments. The onset of metal contamination above background levels occurred at a depth between 43 and 49cm, with maximum concentrations noted near 20cm for Cu, Zn, Cd and Pb. Lead isotope ratios were determined in sediments using sector field ICP-MS, and were found to be 36.5–38.8, 16.5–18.7 and 1.07–1.20 for 208Pb/204Pb, 206Pb/204Pb and 206Pb/207Pb ratios, respectively. Major Australian ores processed at the refinery over the previous ~90years include those from Broken Hill, Rosebery, Mt Isa, Elura, Hellyer and Century deposits. Anthropogenic impact by Pb with Broken Hill type isotopic ratio was initially evident in the core at 43–49cm. The introduction of Rosebery and Elura ores to the refinery was also clearly noted. Pb isotope ratios further highlight that the Derwent River has been exposed to a greater impact by anthropogenic Pb in comparison to other major Tasmanian rivers, namely the Huon and Tamar.

The Influence of Iron Ore Quality Degradation on the Assimilability of Sinter Ore

The sinter production is affected by many factors, including total iron content, gangue content and burning loss. These paper analyses changes of three kinds of Australian iron ores in recent ten years, and then draw a conclusion that the assimilability of these three kinds of Australian iron ores are increased. These kinds of changes cause a lot of influence upon sinter production, which means negative influence. Therefore, ore blending constitution is changed by iron ore quality degradation.

Challenges in Electron Probe Micronalysis 60 Years after Castaing: Examples from Complex Uranium and Rare Earth Element Minerals from Northern Australian Ore Deposits

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Research on High-Temperature Properties of Typical Iron Ores Used in China and its Blending Optimization

High-temperature properties of 10 samples of iron ore from Brazil, Australia and China were measured. Several conclusions were made based on these experimental results. Assimilability of Brazilian ore, Australian ore and Chinese ore concentrate were low, high and medium, respectively. Optimal fluidity of liquid phase was observed in 2 types of Brazilian ores (BR-B, BR-C), 1 type of Australian ore (AU-C) and 1 type of Chinese ore (CH-D). For self-strength of the bonding phase, Australian ore presented low levels, while Brazilian and Chinese ore presented high levels. According to the experimental results of high-temperature properties of iron ore, schemes of ore blending optimization were designed and sinter pot test using these blends were performed. The results indicated that ore blends composed of 30~45% Brazilian ores + 25~50% Australian ores + 20~30% Chinese concentrates presented excellent sintering results, considering both the performance of the processing and quality of the sinter. Therefore this experiment has proved that ore blending optimization combining high temperature properties can lead to more efficient sintering mixes.

Ore characterization, hydrometallurgical and reactive transport studies for in-place leaching of oxidized gold deposits

A proposal for a modified in situ leaching method for extracting gold from oxidized gold ores using a non-cyanide lixiviant is described. A non-cyanide lixiviant is suggested because of the obvious concerns posed by injecting cyanide-bearing solutions into the subsurface. Oxidized gold ores were chosen as a focus because earlier research on the use of sodium thiosulfate as a lixiviant under anaerobic conditions indicated that the presence of pyrite led to rapid thiosulfate breakdown. A reconnaissance research program involving ore characterization and hydrometallurgical test work on samples from four Australian ore deposits and preliminary reactive transport modeling studies was carried out. This work showed that lixiviant-oxidant combinations of sodium thiosulfate and ferric EDTA and iodide and iodine are both capable of extracting high percentages of accessible gold from the selected samples in bottle roll tests under anaerobic conditions. The ore characterization and reactive transport studies suggested that both physical and chemical methods of permeability enhancement may be required to lift bulk permeability and the availability of gold for dissolution to sufficiently high levels to obtain adequate gold recoveries. Assuming that such methods prove to be both necessary and economically viable, the mining method would no longer be regarded as simple in situ leaching. Therefore, the term “in-place leaching” has been adopted for the proposed gold extraction system.

Multi-element and mineralogical analysis of mineral ores using laser induced breakdown spectroscopy and chemometric analysis

In the mining industry the quality and extent of an ore body is determined on the basis of routine assays conducted on drill core and chip samples. Both the elemental composition and the mineralogical classification are important in the characterisation of an ore body for commercial exploitation. Mining industry laboratories typically analyse large numbers of samples from both exploration and mine production environments. At CSIRO we have explored the application of chemometric methods of analysis in combination with laser induced breakdown spectroscopy (LIBS) in order to produce routine quantitative analysis of several ore types including iron, nickel and lead/zinc ores. In particular, principal components regression (PCR) has been applied to perform multi-element analysis of iron ore samples from Australia and West Africa. Calibration models for iron (4.8% Av. Relative Error), aluminium (2.2%), silicon (3.7%) and potassium (1.4%) were determined for the Australian ores. In addition phosphorous measurements were made at trace level for samples from West Africa (5.5% Av. Relative Error). LIBS measurements of segments of a nickel drill core were also analysed using PCR. Mineralogical classification using a combination of LIBS and principal components analysis (PCA) has also been explored. Broad discrimination of ore mineralogy was demonstrated on the basis of the PCA of LIBS spectra in selected emission wavelength bands. The combination of PCA and PCR offers potential for both broad mineralogical and elemental analysis for the minerals industry in exploration and in mine production for the on-line monitoring of ore quality.

Anthropogenic Pb component in hydrothermal ochres from Marsili Seamount (Tyrrhenian Sea)

Recent hydrothermal Fe-oxyhydroxide precipitates (ochres) were sampled during two submersible expeditions to the NE part of the Marsili Seamount summit (SE Tyrrhenian Sea). The Marsili ochres belong to type 1 primary sulfide-poor Fe-oxyhydroxides according to the classification of Hekinian et al. [Hekinian, R., Hoffert, M., Larqué, P., Cheminée, J.L., Stoffers, P., Bideau, D., 1993. Hydrothermal Fe and Si oxyhydroxide deposits from south Pacific intraplate volcanoes and East Pacific Rise axial and off-axial regions. Econ. Geol. 88, 2099–2121]. They are X-ray amorphous, highly metalliferous [Al/(Al + Mn + Fe) ≪ 0.4], low in Si, transition metals (Co, Ni, Cu, Zn, Pb) and rare earth elements (REE) and enriched in B, V and Mo. Their chemical composition and REE distribution patterns indicate precipitation from low-temperature hydrothermal fluid mixed with seawater. Measured Pb isotope compositions in the ochres indicate that the Pb is dominantly anthropogenic in origin. By contrast, the Pb isotope ratios in the nearby higher temperature hydrothermal deposits from the Panarea arc volcano show that the Pb is derived mainly from local volcanic rocks. The fact that the Pb isotopic signature of the Marsili ochres is controlled by recent anthropogenic input suggests that the Fe-oxyhydroxides precipitated from fluids depleted in transition metals. The low 206Pb/ 207Pb ratios in the ochres reflect the contribution of Pb from Australian ores, indicating precipitation of the ochres somewhere between present-day and the beginning of Australian Pb import to Europe. The young age of the ochres and the presence of other hydrothermal deposits along the Marsili crest suggest that the magmatic chamber beneath the seamount may still be alive. This study represents the first observation of anthropogenic influence on submarine hydrothermal deposits.