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By K. G. Wheeland, K. G. Byberg

The occurrence of a secondary, dust-fuelled explosion following blasting of sulphide ores has been reported in mines in many countries, including canada, the USA, Australia and South Africa. However there has been little effort to document the events and develop effective control technology. Following a detailed investigation of an incident at the Geco Di vision of Noranda Minerals Inc. , the company held a conference of interested parties in October 1986 to review the state-of-the-art and to agree on action. '!his paper outlines the causes and effects of such explosions, the key conference points and conclusions, and subsequent information-exchange and teclmology-developrnent activities.

May 11, 1988

By G. R. Guillet

Important resources of kaolin, refractory clay and lignite, not found elsewhere in Ontario, occur with quartz sand of glassgrade quality in unconsolidated Mesozoic sediments of the Moose River Basin in northeastern Ontario. These materials comprise the Mattagami Formation of Lower Cretaceous age, which overlie in some places a thin Jurassic unit and a thick Paleozoic section, and underlie as much as JOO m or more of glacial and marine sediments and a uniform capping of muskeg. The Mallagami Formation is known from deep boreholes to exceed 100 m in thickness and to consist of two phases: an earlier Type A unit of dark-coloured carbonaceous clays and lignite, and a later light-coloured (Type B) unit of kaolin-bearing quartz sands and bright-coloured refractory clays. Remoteness, poor access, and difficult physical environment have inhibited the exploration and development of these resources.

Jan 1, 1984

By Suzie Nantel

Crystalline igneous rocks, known commercially as granite, are exploited in Quebec f rom more than twenty-five quarries for building, ornamental and monumental purpose$. Quebec is the main Canadian producer of construction granite, accounting for nearly 90 per cent of total production. Jn the last three years, this industry has experienced an important growth due to improved marketing and use of modern equipment in rock-cutting and polishing. Jn /983 a 35 per cent sales increase is forecast. The main rock varieties extracted are the following: porphyritic pinkish grey granite and green charnockite from Riviere-dPierre, mahogany brown granite and black anorthositic rock f rom the Lac Saint-Jean area, fine-grained pink granite from Guenette, coarse-grained brown quartz monzonitefrom SaintA lexis-des-Monts. All these rock types occur in the Grenville tectonic province whereas a medium-grained, light grey granite, Devonian in age, is extensively being quarried in the southern part of the Appalachians. In the Superior province a greenish black diabase and a deep red granite are extracted. Search for new varieties and deposits is actively being carried out by prospectors and by the minis/ere de /'Energie et des Ressources du Quebec following growing demand for granitic and gabbroic rocks as dimension stone.

Jan 1, 1984

By JIAQI JIN, Joe Milbourne, Maoming Fan

Gold is very important to support the financial system, and to be used in industries of the jewelry, high-tech fields such as electronics and aerospace, etc. Gold is mainly extracted from three types of ores: primary ore (vein gold), placer (alluvial gold) and associated ore. Cyanide was widely used in gold ore flotation to depress gangue minerals and leaching/cyanidation. The process of extracting gold from gold ore, its separation and flotation concentrate, specifically through a technique called cyanidation or cyanide leaching. This method, which has been dominant since the 1970s, utilizes a dilute solution of cyanide to dissolve gold from the ore. While effective, the use of cyanide raises environmental and safety concerns due to its high toxicity. Cyanide spills can have severe environmental consequences. This has led to the exploration of alternative, environmentally friendly reagents. This paper discusses processing results using the alternative flotation depressants such as sodium sulfite (Na2SO3), etc. to produce a goldrich flotation concentrate for sale to a smelter or as feed to an alternative leaching agent. and methods to extract gold from ore without relying on cyanide.

Feb 22, 2026

By Christopher Newman, Andrew Minckley

With underground stone operations developing in deeper and more geologically complex conditions, accurate pillar stability analysis becomes for the evaluation of engineering design. This paper provides engineering-based recommendations for applying LaModel to evaluate multiple-level room-and-pillar stone mines in both shallow and deep cover. It provides practical guidance on model calibration using field observations, selection of input parameters, and interpretation of results to inform design and operational decisions. The analysis demonstrates LaModel’s effectiveness in simulating pillar load transfer, stress redistribution, and failure mechanisms in complex mining geometries where empirical methods may be inadequate.

Feb 22, 2026

By Kevin Trumble, David Johnson, Kyungjean Min

The electrolytic manganese dioxide (EMD) production through electrodeposition from manganese nodules by reduction leaching in H2SO4 medium using sucrose as reductant followed by purification through 2-stage precipitation methods is described. The purified leach liquor was the starting solution for electrodeposition. Influence of in situ addition of a cationic surfactant Cetyltri-methylammonium bromide (CTAB) (0–500 mg dm −3) on the surface morphology and electrochemical properties of the EMD was examined. The XRD patterns of the deposited material were indexed to the c-MnO2 phase. FESEM results demonstrated that in the presence of CTAB uniform nanofibrous type grains were formed. Higher concentration of CTAB in the electrolytic bath however, drastically decreased the current efficiency (CE) and increased the energy consumption (EC) during electrodeposition. Under the optimum CTAB concentration of 100 mg dm −3 the obtained CE and EC values were 87.64% and 1.70 kWh/Kg respectively.

Mar 1, 2018

By Ming-Feng Ye, Guang-liang Wu

The investigations on chemical composition, mineral composition, embedded figures, texture and microstructure of chrome ores were conducted systematically byvariousanalysismethodssuch aschemical analysis, XRF, SEM, and MLA 650 system. The results showed that there are 92.66% chromite and a small amount of chlorite and forsterite as the main mineral compositions, the content of quartz is very low. Elements as Cr and Fe are almost all present in chromite. The content of Cr O is 41.84% and Cr O /FeO is 2.1. The main ele- 2 3 2 3 ments in the chromite are Cr, Fe, Mg, Al, O; the main elements in the chlorite are Mg,Al,Si,OandasmallamountofFe;themainelementsintheforsteriteareMg, Si and O. On the basis of clarifying the mineralogical characteristics, to produce high-grade alloy, this ore should not be separately put into the submerged arc furnace without pretreating. However, it also seems to be difficult to separate the gangue compositions by the conventional physical upgrading methods, such as magneticseparationandgravityseparation.So,chemicalmineralprocessingshould be taken into account. (cid:1) (cid:1) (cid:1)

Mar 1, 2018

By Dongxing Wang, Zhang Ting-an, Xiaolong Li, Yan Liu

Recent years, bottom blown oxygen copper smelting process has been widely used in China. Besides many advantages such as autothermal operation, this technology is still in developing stage. This topic aims at promoting the dispersion of materials charged into the bottom blown smelting furnace used in the process. Based on the similarity theory, a 1/5 scaled physical model of smelting furnace was constructed. Polypropene particles were used as charged materials. High-speed camera was used to record the phenomenon of the particles dispersion under different gas-flow rates, nozzle diameters and installation angles of nozzles. Image processing software was used for obtaining the particles concentration under different conditions. Results show that when the gas flow rate increases, charged materials disperse better. With the same gas flow, the increasing of nozzle diameter promotes the dispersion effect of materials. The effects of installation angles are opposite for nozzles with diameter of 2.50 and 5.92 mm.

Mar 1, 2017

By C. G. Bastos Andrade, F. R. Valenzuela Diaz, S. M. Toffoli

The modification of structural clays by chemical processes is a common method. It usually uses strong inorganic acid attacks, aiming at improving the clay’s properties and applications. Among the applications are its use in clay-polymer nanocomposites, cosmetics, medicines, and bleaching clays. Tests using acid attack to modified Brazilian bentonites were successfully performed and, resulted in significant improvement in the clay properties. This paper discusses the use of a Brazilian bentonite modified by acid attack as bleaching clay. The treated bentonite samples were characterized by XRF, specific surface area (BET) and SEM/EDS. The treated clay exhibited improved bleaching capacity for Brazilian nut oil and other Amazonian oils.

Mar 1, 2018

By D. Shaver, M. N. Badonie, J. Newcomer, V. T. McLemore, E. Owen

Rare earth elements and critical minerals have recently become of great economic interest because of their necessity for many new technologies and recent geopolitical unrest affecting the supply and import of resources. The San Juan and Raton basins in northern New Mexico are two structural coal basins that contain elevated concentrations of rare earth elements and critical minerals. These two New Mexican coal basins will be assessed geochemically and petrographically to identify vectors of the rare earth element and critical mineral enrichment. Coalbeds, coal seams, overlying, and underlying rock units will be sampled and characterized to determine any economic viability. Historic data will be compiled into a new and comprehensive coal geochemical database, which will grow with new analyses, and serve as the dataset for this project; this coal resource database will be made available to the public.

Feb 1, 2023

By E. Salinas Rodríguez, I. Rivera Landero, E. G. Palacios Beas, J. Hernández Ávila, E. Cerecedo Sáenz, M. A. Mesinas Romero, M. I. Reyes Valderrama

For this study, a sample of 5 g of copper powders obtained by grinding printed circuit boards of computers fixe to 50 mesh (270 μm) according Tyler® series was used. This sample was wholly characterized by XRD, SEM–EDS and AAS. The leaching medium used wasO2S2O3 2. From the evaluated variables it was obtained an apparent order of the reaction of n = 2.34 s−1, whereas according the effect of partial oxygen pressure it was obtained an apparent order of reaction of n = 0.9516 and the activation energy of system was of 6.5 kJ mol−1, the results so achieved suggest a transport control to the solid–liquid interface. Under certain work conditions such as: S2O3 2 ¼ 0:5M, 500 mL, 750 min−1, P/PO2 = 1 atm, 338 K, 5 g of sample and 9000 s of reaction time, it is possible get up to 97.35% of leached copper.

Mar 1, 2017

By Giacobbe Braccio, Alessandro Blasi, Assunta Romanelli, Massimo Morgana, Corradino Sposato

Yttrium is a strategical material for its several usages in a wide range of industrial production. For this reason, improving the recovery of Yttrium has become a crucial focus for international research. In this scientific activity, the utilization of two extractants, 2-ethylhexyl-mono 2-ethylhexyl ester phosphonic acid (P-507) and sec-octylphenoxy acetic acid (CA-12), working in a synergistic extracting system, has been tested. A series of trials have been carried out to optimize the experimental conditions in order to separate yttrium from a mix of heavy rare earths in chloride media. Tests with different relative concentrations of extractants and a phase modifier (TPB, trybutyl phosphate), with different presaponification rate, have been performed to evaluate the behavior of the synergistic system. Results are very promising to recover and separate yttrium with a high purity.

Mar 1, 2017

By L. Diaz, J. Serp, L. Massot, P. Chamelot, M. Gibilaro

The discovery of NdFeB permanent magnets helps to perform technologies with reduced weight and gives them access to miniaturization. The industrial process of production of the Nd-Fe alloy by electrolysis used to manufacture NdFeB magnets consists in reducing Nd3+ ions dissolved in molten fluoride salts. The electrochemical behavior of neodymium is studied in LiCl-KCl and LiCl molten salt systems, examining reduction mechanisms, potential deposition, and faradaic yields.

Mar 1, 2017

By C De-Vitry

"The large Yandi channel iron deposit (CID) is located in the north-west of Western Australia and is currently mined via open pit methods. Drilling at Yandi is widely spaced and current estimates are mostly linear averages of the surrounding local samples. Linear estimates such as ordinary kriging (OK) based on block sizes that are significantly smaller than the dimensions of the drilling grid are less variable than the unknown reality (Armstrong and Champigny, 1989).Conditional simulation (CS) provides a series of plausible realisations that represent the actual grade variability at a small scale (eg 1 m + 1 m + 1 m). These simulations are very useful for a number of purposes, eg: optimising grade control, stockpiling and blending selection of optimal drill hole spacing assessing resource risk on contained tonnage and metal.At Yandi the major constituents of the ore (Fe, P2O5, SiO2, Al2O3 and LOI) are correlated to varying degrees. Independent CS of each assay variable will not reproduce these correlations. Reproducing the correlations (and the shape of scatterplots) is important if the simulations are used for the abovementioned purposes. This paper examines and compares various methods of CS that aim to reproduce the correlations between the assay variables.The CS methods evaluated in this paper are conditional co-simulation (CCS) using the linear model of co-regionalisation and two other, alternative multivariate simulation methods, which use min/max autocorrelation factors (MAF) or the stepwise conditional transform (SCT) to de-correlate assay variables before performing independent CS. It was found that CCS best reproduced the characteristics (histograms, variogram, scatterplots, etc) of the declustered drill hole data (Figure 1). Whilst simulation using MAF generally produced acceptable results, the method did not adequately reproduce the variance of the assay variables. The univariate statistics, histograms and experimental variograms were acceptable for simulations generated from the SCT. Bivariate statistics, cross-variograms and scatterplot reproduction for the SCT were unacceptable. The latter method produced inferior results because there were insufficient samples to obtain a reliable transform of the third assay variable in the transformation sequence.None of the abovementioned simulation methods provides good reproduction of all the scatterplots. This is due to the presence of clay pods, which cause some scatterplots to display two trends. These clay pods contain higher percentages of SiO2 and Al2O3 than the surrounding CID. The clay pods are generally smaller than the drill-grid dimensions. Thus their locations are typically unknown and they cannot be defined by manual interpretation, eg via wireframes. The locations of the clay pods were simulated via indicator CS. CCS was then performed separately for the clay pods and the CID. This significantly improved the reproduction of the correlation coefficients, the scatterplots and visually the simulation was more geologically realistic. Simulating the location of clay pods followed by CCS of assay variables is the recommended approach for simulation at the Yandi CID.CITATION:De-Vitry, C, 2013. Simulation of correlated assay variables - a case study from the Yandi Channel iron deposit, in Proceedings Iron Ore 2013, pp 137-148 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 12, 2013

By Wojciech Klecan

Cobb County, located on the northwest side of Atlanta, GA, is continually growing and, like many other metropolitan areas, it needs to increase the capacity of its waste water system to meet future demand. The Cobb County Water System (CCWS) is the responsible agency for water distribution, waste water collection and treatment in most areas of the county. CCWS, one of the most progressive agencies in the metro-Atlanta area, is addressing its future waste water capacity needs in the southern part of the county with the construction of the South Cobb Tunnel and Pump Station. This project consists of an 8.8-km- (5.5-mile-) long, 8.2-m- (27-ft-) diameter, tunnel boring machine (TBM) excavated waste water storage and conveyance tunnel; six tangential vortex-flow intakes ranging from 1,533 to 5,700 L/s (35 to 130 mgd) peak flow capacity, two construction shafts, six 1.8-m (6-ft) finished diameter connecting tunnels ranging in length from 6 to 975 m (20 to 3,200 ft) and a 5,700-L/s (130-mgd) wet/dry pit pump station. The pump station will have a semi-circular wet well with a dividing wall that extends almost to the top of the shaft and a spilt dry well for reliable operation. Roller gates will control the flow to the wet well from the tunnel. The pump station will have six 1,420 L/s (32.5 mgd) pumps and two sets of stair wells and elevators. With a finished diameter of 32 m (104 ft) and a depth of 62 m (204 ft), this is the largest pump station shaft constructed so far in Georgia for the dewatering of a waste water tunnel. The pump station shaft was also the highlight of the well attended and successful 2009 Shaft Design and Construction Short Course held in Atlanta, Sept. 10-11. The two-day course was sponsored by the Underground Construction Association of SME and Pennsylvania State University and concluded with a field trip to the pump station shaft. The tunnel starts south of the city of Austell and finishes at the South Cobb Water Reclamation Facility (WRF), located on the banks of the [ ] Chattahoochee River just north of Interstate 20 (Fig. 1). The South Cobb Tunnel will run 30 to 137 m (100 to 450 ft) below the surface, with an average depth of about 91 m (300 ft), through metamorphic rocks (Fig 2). The construction contract was awarded to Shea-Traylor JV with the lowest bid price of $305 million and notice-to-proceed was given on July 14, 2008. Jordan Jones & Goulding, Inc. (JJG) is the project designer and performed the geotechnical investigations. Parsons/Jacobs Associates is the construction manager. The South Cobb Tunnel is CCWS?s second deep hard rock tunnel. The 15.3-km- (9.5-mile-) long, 5.5-m- (18-ft-) diameter TBM excavated the Chattahoochee Tunnel was the first deep tunnel to be construced in Cobb County. Construction began in 2000 and the project was completed four years later. It is located about 16 km (10 miles) northeast of the South Cobb Tunnel in similar geology. It was designed by JJG to meet east Cobb?s long-term waste water capacity needs and provide flow equalization to the R.L. Sutton WRF. The Chattahoochee Tunnel was named ?Outstanding Civil Engineering Project of the Year? by the Georgia Sec-tion of the American Society of Civil Engineers in 2006.

Jan 1, 2009

From the massive equipment that moves the earth, to the parts that keep the equipment moving, it was all on display for more than 35,000 people who at-tended MinExpo 2008 at the Las Vegas Convention Center Sept. 22-24. In the largest show in the illustrious history of MinExpo, the success of the recent commodity boom was reflected in the more than 55,700 hm2 (600,000 sq ft) of floor space that was jam-packed with nearly 1,300 vendors. Among them, the makers of the industry?s largest machines, displaying their latest and greatest trucks, shovels, excavators, drills and other mining equipment. During the nearly decade-long commodities boom, equipment makers have worked hard to keep up with demand while also investing heavily in research and development. The beneficiaries of this R&D is the end user who saw first-hand at MinExpo 2008 the many advances that have already been made in safety, comfort and productivity from all the manufacturers. R&D has also helped spark more talk of automation, which is being used already at some of the world?s largest mines. Caterpillar and Komatsu have worked with the technology in surface mining and Bucyrus and Sandvik are among the industry leaders applying the science of automation to underground mines. Technology has in-creased greatly since the idea of moving massive equipment remotely was first knocked around and the idea of entire fleets operating around the clock seems to be getting closer to reality. But, until that happens, MinExpo attendees were treated to a show that featured some of the most impressive current machines the industry has to offer. In the largest booth space of the convention, Caterpillar (www.cat.com) displayed the culmination of an ambitious $280-million dollar investment, with the introduction of its new mining fleet of four new trucks. The F-series was un-veiled with common features in safety, cabs, engines, frames and bodies and Tier 2 compliant engines. The F series also features a return to the electric drive option. ?When our customers asked us for improvements to our mining trucks, we responded by making a record investment in every single truck in our line, as well as the increased capacity to produce more of them,? said Cater-pillar group president Stu Levenick. ?New technologies have allowed us to make trucks more reliable, easier to maintain and more friendly to the operator and to the environment.? The 793-series is in the 218- to 227-t (240- to 250-st) class that will be available in both mechanical (793F) and electric (793F ac) versions. The electric drive-only 313- t (345-st) 795F was also introduced, while the flagship 797B truck is in the process of being replaced by the new 797F mechanical drive, maintaining its 345- to 363-t (380- to 400-st) target payload. Completing Caterpillar?s new mining truck line will be new versions of the 785 and 789 mechanical drive trucks. The next generation of trucks will be phased into production during the next two years, with the Cat ac drive models expected to go into production in late 2010. The $280-million in-vestment is Caterpillar?s largest commitment ever to the mining industry

Jan 1, 2008

By Lin Li, Wen Shi, Hua Wang

"Specimens of the ultra-low carbon bake hardening steel were soaked for 1 min to 5 min, and then cooled by water quenching. The internal friction experiments were carried out to detect the spectra of the specimens. Results show that Snoek peaks are present in all the specimens, however, an obvious Snoek-Koster peak is found only in the 5 min-annealed specimen. Besides, tensile results indicate that the bake hardening values increase with the annealing time prolonging from 1 min to 3 min, but decrease as the annealing time prolongs further to 5 min. The solute distributions in the specimens were characterized by three dimensional atom probe. Some segregated C and V are found in the 1 min-annealed specimen, and the C and V contents decrease as annealing time prolongs to 5 min.1. IntroductionAs an excellent member of automotive body panel materials, various types of bake hardening (BH) steels have been developed since 1980s. Bake hardening property, as one of the most important mechanical properties, has been studied by many researchers [ 1-5]. As is known, BH phenomenon is generally controlled by the interaction between solute C and dislocations. The Snoek peak of internal friction (IF) is very popular in the investigation of solute C [6-9]. However, result of internal friction cannot suggest the distribution pattern of solute C as well as its influence on BH phenomenon.Three dimensional atom probe (3DAP) can diagnose solute element atoms as well as nano-sized precipitates, and it is the only instrument that currently can identify the identities of individual atoms in a material and measure their spatial coordinates with the resolution close to 0.3 nm [10]. There have been a number of studies about using 3DAP to detect solute elements as well as nanometer sized precipitates [11-19]. For example, Hono et al. [16] used 3DAP to determine the solute elements in an age-hardened Mg-Ca-Zn alloy, and they also obtained the distribution patterns of the observed elements."

Jan 1, 2011

By John Wall

The use of electronic detonators in civil tunnelling applications, to reduce vibration is small firings has been successfully utilised for a number of years. As part of the mining industry’s commitment to reducing blast damage during the development cycle in underground mining applications, a series of development blasts using eDevTM electronic detonators in typical mining applications was conducted in North Queensland, Australia.

Jan 1, 2012

By J Ortiz

In almost all copper mining companies, mine planning is done considering different time frames, leading to long-term (life-of-mine) (LOM), medium-term (first three years) and short-term (first year, monthly, weekly, and up to daily plans). Shorter term plans are usually associated with more abundant information, hence models with lower uncertainty. However, they capture more of the variability found on the geological attributes. In long-term models, usually estimation methods tend to hide this variability, providing smoothed interpretations.Medium and long-term plans consider average values for the parameters and optimisation techniques are applied aimed at maximising the economic profit. Short-term plans, on the other hand, are made to comply with the medium-term promises, maximising the use of the available resources (equipment and processing capacities) and dealing with the variability not characterised in the previous planning stages. This generates an important gap between the short-term and the medium and long-term plans. A case study was made using an important oxide copper mine, where the variability found in the short-term plan has a large impact in the productive process, thus reducing the daily ore grade variability is an important goal. In this paper, this planning issue is addressed by creating medium-term mine plans using mixed integer programming which are compared using the output of a simulation of the daily extraction that is aimed at satisfying the daily constraints of the processing plant, the availability of mining equipment and the variability of ore grade. The result shows the expected gap between these mine planning processes, which suggests correcting some of the parameters used in future medium and long-term plans.

Sep 26, 2011

By T J. Laing, A B. Richards, A J. Moore

Blastholes fired in a pattern with a constant initiation delay create a frequency in the ground vibration similar to that from a percussion instrument, such as a drum, in the air. A constant firing delay generates a prime or forcing frequency into the ground motion. The forcing frequency may then be modified by ground transmission characteristics into subharmonics of the forcing frequency. The moving vibration source between blastholes also creates a frequency shift because of a Doppler effect. Other wave interactions may form beats. The effects are exacerbated by the accurate firing times of electronic detonators. This paper demonstrates how observations of wavetraces and frequency spectral analysis were used to recognise:Doppler effect and frequency ellipsoidssubharmonics (and sub-subharmonics) of the forcing frequencybeat formation that may double or triple peak particle velocity (PPV) levels.Recognition of beats permitted techniques to be used to control ground vibration from coal overburden blasting to limits deemed to cause no further instability in a slip failure. An understanding of the science involved has practical application elsewhere that has been successfully applied to initiation timings to reduce PPV and adverse human and structure response from other blasting operations.CITATION:Moore, A J, Richards, A B and Laing, T J, 2015. Blasting harmonics and controlling peak particle velocity, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 527–532 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015