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By John L. Bonus

"WITHIN THE BROAD PARAMETERS implied by the title of my speech, I propose to deal more particularly this evening with a subject the many aspects of which have constituted the essential elements of one of the main thrusts undertaken by the MAC in the past two years, i.e., to create among Canadians a much greater awareness of the importance of mining and to demonstrate to them what are the many and varied benefits they derive from mining activities across their country. In other words, MINING - WHAT IT MEANS TO CANADA.I also intend to discuss some aspects of government-industry relationships.I am very conscious of the fact that I am speaking to an audience made u in large part of experts in several fields of mining and exploration activities. They will be familiar with many of the points I intend to discuss. However, without in any way suggesting that familiarity breeds contempt, might I emphasize that even in this particular forum there is justification for reiterating some of our basic philosophies and suggesting ways whereby they might be better understood and promoted.Let us first summarize the present dimensions of the Canadian mining industry."

Jan 1, 1971

By China University of Mining & Technology, Yuemin Zhao, Bo Zhang, Liang Dong, Zhenfu Luo, Chenlong Duan

"In China, approximately 65% of coal reserves are in the west region, where water shortage is a serious problem: high-efficiency dry coal beneficiation technology is desired. Using magnetic powder and fine coal as heavy medium, and using air as the fluidizing agent, a novel air dense medium fluidized bed separator is proposed for coal preparation. Coal can be efficiently separated according to density in the fluidized bed, where bed density is steady. The separator is highly reliable, the circulation quantity of heavy medium is low, and the gas distributor cannot be easily easily. The world’s first industrial modularized dry coal preparation plant was built by China University of Mining and Technology. Dry coal beneficiation technology was first used to produce low-ash coal. Results of industrial production show that the ash content of clean coal is 3.46%, the probable error E value is 0.055 g/cm3, and the organic efficiency is over 90%. The advantages of the modularized dry coal beneficiation system are the high separation accuracy, the simple process flow, the low operation cost, low energy consumption, and so on. This technology provides a new effective method for coal separation in acid region and coal tending to sliming.INTRODUCTIONCoal is the most important primary energy source in China, where coal output reached 3.68 billion tons in 2013 and represents approximately 68% of the primary energy consumption. Coal has made a great contribution to the development of the Chinese national economy, but it also brings serious environmental pollution. However, approximately 65% of coal reserves are in the arid west region in China where water shortages present a challenge for wet coal preparation technology. In addition, the abundant lignite resource, because it is easy to mud in the water, should not be treated with the wet separation method. Therefore, it is critical to develop highly efficient dry coal preparation technology to meet the demand in arid areas. Further, water resource shortages are a global problem, thus the development of efficient dry coal preparation technology in has potential application in other water-short countries like South Africa, Brazil, India and Turkey."

Jan 1, 2016

By Beall, John V.

THIS is not simply the story of how a water filled shaft was developed into a million-ton- a-year producing mine in the space of four critical years, although it is reason enough for telling it, but it is also the saga of an engineering achievement in which knowledge nurtured by years of experience in coal and ore mines was blended together and the best from each type of mining selected. The entire system of mining was detailed on maps by the mining engineering department before the shaft was unwatered, and subsequent development followed these plans nearly to perfection. The selection of machinery was particularly critical as it was necessary to push production from only a few headings in the early stages of development and metal mine machinery was being used in a coal panel-system of mining. At the start of World War I1 the demand for iron ore to supply Woodward blast furnaces, and rapid exhaustion of the main source of Wood- ward ore, No. 3 Red Ore mine, necessitated speedy opening of the Pyne mine. The mine is three miles southwest of Bessemer and is responsible for 80 pct of Woodward ore, the rest coming from the Songo mine. The Woodward Iron Co. is one of the old producers of the Birmingham district. S. H. Woodward, an iron-master of Wheeling, overheard two Union soldiers conversing about ore and coal lands in Alabama, which lead to the acquisition of the first ore lands of the Woodward Co. in 1869. Development was not begun until after the death of S. H. Woodward; his two sons, W. H. Woodward and J. H. Woodward, formed the Woodward Iron Co. in 1881 and purchased a tract of land midway between the ore vein on the southeast and the coal field on the northeast about 12 miles southeast of Birmingham for the

Jan 1, 1950

By Marcelo A. Martorano, Moyses L. Lima, João B. F. Neto

"Directional solidification is an essential refining step to obtain solar grade silicon from metallurgical silicon. This step can be carried out in a Bridgman furnace, where nearly constant temperature gradients and solidification velocities are imposed on the solid-liquid interface. In the present work, this directional solidification was conducted in a static furnace, in which large temperature gradients and low solidification velocities were enforced to increase macrosegregation. The resulting ingots were analyzed regarding their macrostructures, microstructures and chemical composition. Using measured cooling curves in the ingot as boundary conditions, a mathematical model based on the concept of a stagnant liquid layer at the solid-liquid interface was implemented to predict the macrosegregation profiles. The chemical analyses of the ingots show macrosegregation of several impurities to the ingots top. The mathematical model indicates that liquid convection plays an important role in stabilizing the planar solid-liquid interface, increasing the macrosegregation of impurities.IntroductionMost of silicon used for photovoltaic (PV) energy production is obtained by chemical processes, such as, Siemens and its derivations [1]. However, these chemical processes have drawbacks related to relatively high energy consumption and investment costs, and to safety and environmental problems. In order to overcome these difficulties and to fulfill the silicon demand for PV applications, several metallurgical routes are under development [2] to produce silicon of enough purity to PV applications (SoG-Si) from metallurgical grade silicon (MG-Si).Metallurgical routes involve different steps among which the directional solidification is pointed out as a fundamental one [1]. Directional solidification can cause macrosegregation of impurities to the last part of the ingot to solidify. The impurity segregation during solidification is related to the low solute partition coefficient (k0) between liquid and solid silicon. Most of the impurities in MG-Si have k0 << 1, except for boron, phosphorus and oxygen, which require specific steps of the metallurgical routes to be eliminated. The equilibrium partition coefficient and the solubility limits for the most important impurities in MG-Si are shown in table 1"

Jan 1, 2014

By S. J. Hogan, T. William

"By the year 2000, the steel industry, not only in the United States but in the rest of the world, will undergo significant changes. On the other hand, there will be a number of areas in which change will be minimal.The current capacity of the industry worldwide is approximately 800-810 million metric tons. This may grow to some extent, as Third World countries install capacity. However, much of it will be neutralized as the industrialized countries shrink their current capacities.There will be several breakthroughs in terms of technology, some of which deal with the production of iron outside of the blast furnace. However, these processes will not be far enough advanced by that time to replace the blast furnace, rather they will supplement it.In terms of steelmaking and the subsequent rolling process, there should be a number of basic improvements. The strip mills will roll sheets with a very slight variance in gauge, which will give the customers a better product for automatic stamping machines. Ordinary carbon steel, in a number of instances, will be replaced by high-strength, low-alloy steel, which will reduce the tonnage necessary for present-day applications, such as construction.The corporate organization will be significantly changed as joint ventures and mergers will reduce the number of companies, as well as facilities in operation. This will enable the industry to reduce its capital investment and improve operating costs, so that it will be able more effectively to compete with other materials, such as plastics, cement, aluminum, etc."

Jan 1, 1988

By D W. Nisbet

Today Hudson Bay Mining and SmeltingÆs 777 Project is the largest mining construction project under way in Canada. The project comprises six components: construction of the new 777 zinc-copper mine; construction of the new Chisel North zinc mine that will truck ore out from 600 metres below surface; expansion of the Flin Flon ore concentrator; expansion of the zinc plant to increase throughput by 15 per cent; a spill gas project that will reduce fugitive gas emissions by some 90 per cent; and infrastructure improvements including construction of a new electrical substation. Total investment in The 777 Project is over $US 260 million. Seven years ago, the Flin Flon, Manitoba-based company was fighting for its very existence. How does a company go from down-for-the-count to robust contender in just seven years? Contributing reasons are many, but all have their root in a process HBMS calls æTransformationÆ. It is transformation that has taken HBMS, a very traditional company, through a very non-traditional turnaround (Figure 1).

Jan 1, 2000

"Liberation is a key requirement for efficient separation in mineral processing. As a consequence of this an understanding of the inherent textural features of an ore is no longer possible since during the process of liberation, texture is destroyed. Knowledge of key textural features, such as mineral grain size and distribution, prior to breakage processes provides the opportunity to understand the textural drivers for ore hardness. Modern characterisation methods, including automated SEM-based techniques, provide the possibility of measuring mineral characteristics at a range of scales. This paper discusses how textural features of two different ore types in a porphyry copper deposit can be measured and interpreted at a number of scales. Standard breakage tests conducted on the ores indicate that one of the ores can be characterised as hard and the other as soft. The impact of mineral grain size and the presence and scale of vein type structures in the two ores have been used to determine the extent to which these features influence ore hardness.INTRODUCTIONIn order to effectively convert ore into metal, knowledge of both the processing stages and the characteristics of the ore are essential. Prior to the advent of technologies that enabled the fundamental understanding of the sub-process at each stage of processing and the measurement of appropriate ore properties the most effective way to understand how an ore would respond to a process was to put it through that process, for example the way to determine how an ore would break was to first break it. Existing comminution models seek to predict the size distribution of rock fragments as the result of applied energy based on knowledge of the rock strength. It is common for these models to consider the rock as homogeneous and despite providing important data for the design and optimisation of industrial comminution circuits these models are only applicable within a narrow range of operation. In order for reliable predictive models to be developed that account for the inherent ore characteristics, a step change is required in the type of measurements that are carried out to characterise an ore and the type of data that is extracted and used as model inputs."

Jan 1, 2016

By B King

A large number of mineral deposits contain regions in which it is economically beneficial to extract ore both via open pit and underground mining techniques. Current industry practice lacks an effective means to establish the extent of the open pit and underground mining areas for an individual deposit. We present a mixed integer programming model for scheduling both the open pit and underground mine that can be used to create a holistic extraction sequence for a specific deposit. The model considers both spatial and temporal elements of the open pit and underground mines in order to maximise the net present value of the entire deposit, while adhering to its production, processing and block sequencing constraints. By doing so, we can schedule the open pit and underground in concert.CITATION:King, B, 2014. Modelling open pit and underground production scheduling in concert, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 369–374 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By S Hawker, M Gibbs, A Craven

Current climate change projections suggest both an increase in the intensity of significant rainfall events and an increase in the variability of rainfall in some regions of Australia. It is necessary for mine site owners and operators to understand the effects that this potential shift in climate may have on their operations. The ability to maintain compliance with discharge regulations and operational security for those sites that rely on surface water run-off harvesting may be negatively impacted if some current climate change projections are realised. Although current regulations require the preparation of water management plans, these are generally developed using historical climate records for the site in question and as such do not give any indication of a siteÆs resilience to the influences of climate change.This study compares design and operational considerations for a case study mine site using historical rainfall records and modified records representing climate change projections. The future climate models are invariably broad scale and are limited in their capacity to be downscaled to a reasonable resolution for developing a site water balance. Instead the local historical data set has been modified to concentrate precipitation to peak periods and propagated through the model. The study looks at the siteÆs response to the potential changes in climate.It is shown that if current climate change projections are realised, this will have a significant effect on both the necessary size of designed surface water infrastructure and operational considerations on-site. A discussion is presented on the potential risks that climate change presents to mine sites and the range of options that could be considered to mitigate these risks. Depending on a number of factors, including location and risk profile of the owner/operator, resilience to climate change can be addressed as either a capital or operational expenditure (CAPEX/OPEX).CITATION:Craven, A, Hawker, S and Gibbs, M, 2013. Site water balance response to variable climatic conditions, in Proceedings Water in Mining 2013 , pp 211-216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By J. Feldman

This report contains a description of the distillation laboratory at Bruceton, Pa., which was established to aid in the separation and identification of the products produced in the synthetic liquid fuel processes under study there. Compounds present in synthetic liquid fuels may include aliphatic from C1 to C60 or greater. Alcohols, ketones, esters, aliphatic carboxylic acids, saturated hydrocarbons, olefins, and diolefins are all found in Fischer-Tropsch products. Coal-hydrogenation products contain, in addition to aliphatic compounds, a large proportion of naphthenic material and aromatic compounds ranging from benzene to coronene; in addition, appreciable quantities of tar bases and tar acids are present. In designing the laboratory, therefore, provision had to be wade for the greatest amount of flexibility and versatility. A great deal of standardization of basic equipment had also to be designed to permit interchange of parts and services.

Jan 1, 1951

By Dennis Greene

Real-time GPS position monitoring of mining equipment is becoming more and more commonplace. Digital mining plans can now be used onboard properly equipped earthmoving equipment and excavation status is available in real-time via high bandwidth data radio systems. These systems provide a closely integrated link between operations and planning. No longer must operations wait for or be hindered by insufficient survey marks, nor is engineering delayed by lack of timely mine status information. Unprecedented efficiency gains become feasible -from the engineering office, to drilling and mucking, to reclamation, as well as in mine construction projects. Direct economic benefits of these systems will be explored as will the less tangible, but very significant, indirect operational efficiency gains.

Jan 1, 1998

By C. J. Parradies

During injection into a die, semi-solid metal alloys exhibit a shear-rate, history-dependent flow response. Simulating the injection of a thixotropic material requires that empirically determined boundary conditions and viscosity are specified as a function of both temperature and shear rate history. Experiments were performed using an industrial die casting machine that was instrumented with sensors to measure the pressure and temperature during the injection of a semi-solid aluminum alloy through a tube. This benchmark experiment was used to develop a simulation of the die casting process that could then be applied to more complex die geometries. The results of the experiments were analyzed using the exact, steady state solution for a power law fluid and simulations accounting for slipping at the boundary between the semi-solid metal and the die. Results indicated that the no-slip condition cannot be used to simulate the velocity boundary condition, because the measured pressure is much lower than that predicted by the models. An estimated apparent slip coefficient was introduced to account for the reduced pressure. During some of the experiments, a sudden drop in the measured pressured, prior to decreasing the ram velocity, coincided with observations of segregation in the form of concentric rings visible on the polished surface of cross-sections cut from material remaining in the tube.

Jan 1, 1997

By Q. Li, X. -L. Lei

Accompanying global energy shortage and high energy prices, shale gas has been the focus of exploration and it has attracted great attention from both academia and industry. The combination of horizontal drilling and hydraulic fracturing enables the extraction of huge quantities of shale gas from impermeable shale formations. During the process of hydraulic fracturing, great amounts of water, sand and chemicals must be injected into the shale formation at a high pressure, which may trigger seismicity. Such events could occur due to the presence of faults or the reactivation of these potential faults. Shale is the main component of source rock in the Sichuan Basin, China, and has the greatest contribution to the natural gas of the basin. In order to investigate the fracturing mechanism of shale in the Sichuan Basin, China, a series of rock fracture tests under triaxial compression were carried out in the laboratory in order to investigate the hydraulic fracturing behavior in relation to the seismicity. Based on the high multichannel waveform recording system, the detailed spatio-temporal distribution of acoustic emission due to micro-cracking was used to examine the deformation and fracture behavior of shale. In addition, the effects of confining pressure on the deformation and fracture in shale under triaxial compression by acoustic emission monitoring and X-ray computed tomography were discussed in the paper. The experimental results indicate that the shale samples demonstrate brittle fracture behavior. The confining pressure has a great effect on the complexity of the fracture planes and the spatial distribution of acoustic emissions, but few contributions to the location of the major hydraulic fracturing plane. The foliation of shale plays a dominant role in the rupture process and the geometry of the major hydraulic fracturing plane. The high confining pressure increases the strength and restrains the deformation of shale during compression process. These results shed some light on the understanding of onset of hydraulic fracture initiation not only for shale gas exploration and production, but also for CO2 geological storage and underground energy storage.

Jan 1, 2015

By Edward Rosenberg

The synthesis and characterization of silica polyamine composites modified with a variety of sulfur containing ligands is described. The two most successful ligands in terms of sulfur in-corporation and mercury capture are ethylene sulfide and carbon disulfide. The ethylene sulfide forms either an amino mercaptane or a polysulfide upon reaction with amino groups on the composite. The carbon disulfide undoubtedly forms a dithiocarbamate functional group upon reaction of the amino group under basic conditions. Both materials posses excellent capture kinetics and capacities for mercury, Once captured, the mercury is extremely difficult to remove from the composite materials, even with concentrated acids, and they easily pass the TCLP test. The materials are compared with related thioether modified silica polyamine composites and appropriate potential applications are discussed.

Jan 1, 2003

By L Köresaar, J Moilanen

With lower and increasingly variable Fe grades in iron ore resources, the monitoring of Si, Al, Mg and other light elements to meet quality requirements is gaining importance in the iron ore beneficiation industry. The high cost per manual assay and associated manpower requirements often limit the frequency of shift composite samples and laboratory assays. Furthermore, the shift composite assays represent past performance of a plant but are not useful for immediate reactions to feed variations, detection of equipment malfunctions or process control. Automated online analysis of light elements radically reduces the cost per assay and provides repeatable, timely data for process analysis, control and optimisation.A light element online slurry analyser, based on laser-induced breakdown spectroscopy (LIBS) optical emission technique, will be presented. This paper discusses the analyser design for the iron ore industry and also reviews the performance of the analyser against the manual laboratory. Additionally operator safety, user friendliness and maintenance requirements are discussed.A case study will also be discussed in this paper. The sophisticated measurement technique has been implemented in an industrial automated analyser and sampling system to allow for slurry measurement for up to 12 sampling points. However, careful selection of the sampling points and implementation of the sampling system is required for smooth operation.CITATION:K&#246;resaar, L, Timperi, J and Moilanen, J, 2015. Optimised process control in iron ore via online analysis of light elements, in Proceedings Iron Ore 2015, pp 511–518 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By A. O. Dufresne

WITHOUT transportation, mining would be quite impossible. Any person familiar with the operation of a mine knows full well that from the minute ore is blasted, it is kept moving until it reaches the treatment plant. In the mill, by means of conveyors and elevators, the ore is brought from receiving bins to one machine after another until finally its valuable mineral is separated from the gangue. The finished product must then be shipped -either by boat, rail, or motor trucks to industrial centres, where it undergoes further treatment and transformation into finished commercial goods. Everybody appreciates that the winning of an or-e includes, amongst various operations, the moving of large quantities of material of generally low value. Transportation, therefore, must be considered One of the most important factors in the economics of mining. My assignment, this afternoon, is not to treat of that phase of transportation as it directly affects mining operations, but rather to consider some of the aspects of overland transportation and its influence in bringing about the development of mining camps in Canada. I shall take the liberty of rapidly surveying conditions facing prospectors, mine developers and operators from the time a region is still in a pre-pioneering stage until such time as a mine starts shipping its concentrates.

Jan 1, 1956

By Walid El Kamash, Sadik Oztoprak

"Soft soil presents a challenge against multistory buildings in some cities of Egypt such as Port Said due to the consolidation settlement. Deep mixed (DM) columns are used to improve the soft foundation soil in order to reduce the total and differential settlements. Latest research revealed that this improvement technique also increases the rate of mechanical consolidation due to column yielding caused by stress concentration from the soft soil. In this study, extended poly-styrene (EPS) Geofoam is used to replace the soft soil over DM columns in order to control the stress concentration and settlement. To understand the effect of EPS geofoam on the degree of consolidation, stress concentration and settlement, a parametric study was carried out through a mechanically and hydraulically-coupled numerical method. A unit cell model is used, in which the soil was considered linear elastic; DM column and EPS Geofoam are elasticplastic materials. Results reveal that EPS geofoam is helpful for reducing the settlements and accelerating the consolidation. Increasing the length of the column of the deep mixed foundation with EPS geofoam has a significant effect on accelerating the consolidation.INTRODUCTIONExpanded polystyrene (EPS) geofoam is a lightweight polymeric material which is made by expansion of raw plastic beads. The expansion of the EPS beads are spherical-shaped particles containing closed hollow cells. EPS which plays an important role as an innovative lightweight construction material is now well recognized due to its low density in addition to high compressive and rupture strength. Inglis (1996) reported the first use of EPS geofoam as a seismic buffer to reduce potential seismic loads against a nonyielding basement wall. Gaskin (2000) and Bathurst et al. (2007) carried out reduced-scale shaking table test on a rigid retaining wall protected by EPS geofoam. The test data showed that the peak lateral loads acting on compressible model walls were reduced below values measured for nominally identical structure but with no compressible inclusion. Abdelrahman and El Kamash (2014) investigated the behavior of EPS Geofoam beneath raft foundation on soft soil of Port Said. They showed the ability of EPS to control vertical displacements. The investigation of the behavior of EPS geofoam with DM column has not attracted more attention of previous researchers. In this paper, the behavior of replacing the soft soil by EPS geofoam was examined in the presence of DM column."

Jan 1, 2015

By D. H. Baker

These investigations were conducted to determine the feasibility of molten salt electrorefining of zirconium scrap, offgrade sponge, and alloys under contract number AT(11-1)-475 between the Atomic Energy Commission and the Federal Bureau of Mines. Offgrade zirconium sponge having a Brinell hardness of 169 can be refined by this technique to produce metal having, consistently, a Brinell hardness of less than 90. Also, zirconium alloy scrap, approximating zircaloy-2 in composition, can be refined to recover zirconium metal with a Brinell hardness of less than 100 that is essentially free of the major alloying elements. Analysis showed that the quantities of these elements were decreased as follows: iron from 0.27 to 0.002, tin from 1.36 to 0.001, nickel from 0.02 to 0.001, and chromium from 0.12 to 0.002 percent.

Jan 1, 1961

By C. A. Nogueira, F. Margarido

"A research work has being carried out annmg at evaluating the possibility of treating simultaneously several electrochemical systems of spent batteries using the same process, in order to overcome the high costs and difficulties of selective collection and sorting. Zn-Mn02 systems, representing more than 75% of portable battery market, shall be treated in dedicated processes. The treatment assessment using a single hydrometallurgical process of the other major systems (NiCd, NiMH and Li-ion), having Ni and Co as main metals, was the aim of the research work here reported. Sulfuric acid leaching was demonstrated to be adequate for dissolving more than 90% of the metals of interest contained in batteries. The subsequent separation of metals by solvent extraction, using organophosphorous extractants like DEHPA and Cyanex 272, allowed the production of pure solutions of rare earths, cadmium/manganese, cobalt, nickel and lithium, enabling their further recovering.IntroductionRecycling is the best approach for end-of-life management of spent batteries mainly by environmental reasons but also motivated by resources conservation and, in some cases, by economic profits. Most relevant electrochemical systems of portable cells are Zn-Mn02 (ZMB, alkaline and saline), nickel-cadmium (NiCd), nickel-metal hydride (NiMH) and lithium-ion (LIB). These batteries are collected, sorted and usually treated separately, applying for pyrometallurgical or hydrometallurgical technologies, the former being the most common.Several processes have been developed and some of them industrially applied, as described in some available review papers [l, 2]. In Europe for ZMB systems the oldest processes are Batrec [3] and Citron [4]. Although having differences in details, both are based on pyrometallurgical recovery of zinc by distillation, in metallic or oxide forms, being manganese retained in the slag together with iron. Hydrometallurgical alternatives are also available, like Zincex [5] and Recupyl [ 6] processes, both using sulfuric acid solutions as leachant. The application of the existing technologies to battery recycling, instead of using dedicated processes, is other alternative already tested, being the Waeltz furnace or the Imperial Smelting some examples."

Jan 1, 2012

By Bradford H. Miller

Separation and Recovery Systems, Inc. (SRS) provides on-site waste minimization and resource recovery using its state-of-the-art MX-1500 centrifuge and MX-2000 thermal desorber. The MX-1500 can process over 450 feed tons of material per day, resulting in centrifuged cake containing 20% to 60% by weight. The MX-2000 is a hollow-flite thermal processor indirectly heated by either steam or hot oil. SRS has dewatered and/or deoiled over 1,000,000 feed tons of material in the refining, chemical, and energy industries using the MX-1500. SRS estimates that over 300,000 barrels of reusable oil have been recovered from that material. Additionally, SRS has dried and/or detoxified over 150,000 wet tons of solids or soil to regulatory or customer-specified limits using the MX-2000.

Jan 1, 1994