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By H. C. Boydell

Introduction Situated in the district of South Lorrain, some 16 miles southeast of Cobalt, Ontario, and reached from that centre either by branch line of the T. & N. O. railway or by what, for a mining camp, is a reasonably good road, the Keeley mine, owned by the Keeley Silver Mines,' Ltd., has had its history recorded by C. W. Knight (1). Silver was first discovered in South Lorrain, in Woods' vein, on Keeley property, in 1907, and the Keeley mine has been described by Knight (2) and Bell (3). The total production to February 28th, 1930, has been 10,760,107 ounces of silver and 1,285. 434 pounds (weight) of cobalt.

Jan 1, 1931

By P. H. Agson Gani, T. Sitorus, N. P. Widodo

"PT ANTAM UBPE Pongkor underground mine use blasting to develop its tunnels which will cause poisonous and dangerous gases trapped inside mine. To analyze this case, a study of mine ventilation, the dispersion of carbon monoxide (CO) gas concentration and diffusion coefficient is commenced. At the end, the re-entry time formula will be determined. Results indicate that this study is site specific and could only be applied in the place this study executed. The aim of this study is to be further developed by applying Principal Component Analysis (PCA) to find a universal re-entry formula. KEYWORDS Mine Ventilation, Re-Entry, Smoke Clearing, Diffusion Coefficient, Carbon Monoxide Gas, Gas Dispersion INTRODUCTION Pongkor underground mine is using cut and fill as its mining method. Thus, its development and production processes require blasting to develop its tunnel. This process caused poisonous and dangerous gases spread and trapped inside the mine, one of them is carbon monoxide (CO) gas. CO is formed in an unbalanced reaction of explosives detonation and could be the cause of headache, blackout and death to people who inhale CO at certain concentration (McPherson, 2011; Hartman, Mutmansky, Ramani, & Wang, 2012). Mine ventilation system is installed in the mine to resolve this problem. Mine ventilation play an important role to disperse CO gas by absorb the poisonous/dangerous gases and deliver clean air into mine. The important parameter is diffusion coefficient, because diffusion is affecting particulates or gasses spreading from its sources throughout the mine. Diffusion coefficient is the total diffusion in axial direction of turbulent flow mainly by convection of bulk motion, advection and eddy diffusion, while the effect of molecular diffusion is appreciably negligible (Widiatmojo et al, 2015). Taylor (1953, 1954) develops a theory about the dispersion by inducing a slow stream of solvent into a capillary tube. Taylor used Reynolds assumption of radial diffusivity to be analogous with the transfer of the matter in turbulent flow as well as the transfer of momentum and heat. Then, Taylor proposed the formula of diffusion coefficient, D (m2/s), against pipe diameter and turbulent shear velocity are as follow:"

Jan 1, 2019

By Y. Yhang, D. C. Sego

ABSTRACT This paper evaluates the potential of freeze-thaw dewatering using Albian mature fine tailings (MFT). Freezing tests were first performed to study the effect of freezing rate on dewatering efficiency. Lower freezing rate resulted in higher thawed solids content and shear strength. Subsequently, large strain consolidation tests were conducted to investigate consolidation behaviour and how it is affected by freeze-thaw. The consolidation behaviour was presented in terms of effective stress versus void ratio and permeability versus void ratio. The results can be used to predict the field behaviour of Albian MFT and optimize the application of freeze-thaw for MFT dewatering.

Jan 1, 2014

By C. M. Kleemann

The paper describes the present milling practice at Western Mining Corporation Limited's new nickel mine at Kambalda in Western Australia. It details the crushing, autogenous grinding, flotation and spray drying circuits for the production of a nickel concentrate. It also indicates some of the metallurgical problems which have been encountered in concentrating this ore.

Jan 1, 1973

By S. Tavani, T. Rees

The current mining operations at Newmont Boddington Gold Mine (NBG) commenced in 2008, and commissioning of the processing plant started in the latter half of 2009. Metso Process Technology and Innovation were engaged to assist NBG with commissioning and project ramp-up through the implementation of a comprehensive “Mine-to-Mill” Process Integration and Optimisation project. This methodology entailed extensive data collection which included drill and blast audits, ore characterisation, comprehensive comminution circuit surveys and review of operational data to assess the limitations within the current mining and processing operations. The results of these investigations have been used to define the operating base line of both the mining and processing areas and identify improvement opportunities. The use of modelling and simulations, utilising actual production data, has allowed for multiple scenarios to be evaluated, minimising the requirement for actual trials and thereby minimising impact on the operation. Improvements implemented to date include: the introduction of routine rock strength measurement for inclusion in block models, modifications to blast design improving ROM fragmentation and downstream comminution process performance, and changes to improve performance of secondary crushing and grinding circuits. Close cooperation between the mine and plant personnel is playing a significant role in overcoming the challenges presented to this operation and further improvements are targeted for the second full year of process plant operation.

Jan 1, 2012

By Paul Hughes

Purpose of Research ? What are the loading mechanics of paste against barricades? ? What is the capacity of the composite paste fill fences? ? Based on the loading mechanics of the paste, do the fill fences pose a risk of failure? Outline ? Glossary of Terms ? General Introduction ? Research Methodology ? Site Description ? Instrumentation Program ? Results ? Analysis ? Conclusions ? Recommendation for Future Work

May 1, 2008

By B. A. Zaharov, J. M. Shneerson, L. V. Chugaev, M. T. Zhunusov, A. M. Markelov, S. V. Drozdov

The main direction of research was the application of autoclave technology for the flotation concentrates or biooxidation feedstocks. The industry modernization also expects the possibility of increasing the yield of the flotation concentrate, to allow an increase in gold extraction in flotation circuit. This paper provides brief description of results obtained for concentrates with the yield of 4 and 8%, as well as corresponding biooxidation feedstocks. Technological efficiency of autoclave oxidation is shown for both concentrates and biooxidation feedstocks. The process has been evaluated on a laboratory and a continuous pilot plant scale. Gold extractions from POX discharge are ranging from 94-97% for each product, with only 5-7 kg/t cyanide consumed.

Jan 1, 2014

By Brian L. Beninger

This paper discusses the application of the computer to coal preparation process predictions. In broad terms, the computer is used to perform two main functions. Firstly, the given float-sink analysis is interpolated and extrapolated to cover the entire actual range of raw coal specific gravity. Assumptions based on historical data must be made at times. Secondly, the partition curve, which, from historical data, defines the efficiency of a specific coal washing process, is applied to the washability data in order to determine the expected clean coal yield and quality. The vast amount of numerical work which is required to make a prediction of this type exhibits the need for computer methods in this area.

Jan 1, 1979

By Werner Unland, Nick Holl

"The paper presents the engineering design and experience gained so far with a dewatering system for an open-pit uranium mine planned at Key Lake in Northern Saskatchewan.The results of hydrogeological investigations preceding engineering exhibit an extensive unconfined overburden aquifer hydraulically connected with the underlying Athabasca Formation and basement rocks, both of relatively low hydraulic conductivity. The overburden aquifer is embedded in a bedrock trough, with the deepest depression between the planned pits. The hydrogeological data were used in a numerical dewatering model simulating groundwater flow atdifferent stages of the pit development.Based on the model results, the engineering design had to provide for different pumping rates, varying between 1.0 and 0.21 ms/sec. This problem was solved by using a double line pressure system. The design concept for the complete peripheral discharge system and the well design used for 26dewatering wells are discussed.Experience with reverse-circulation techniques applied for the construction of the dewatering wells is presented. Theoretical and practical considerations which led to the constructionof wells of different diameters are discussed.The design of the in-pit dewatering system provides for seepage ditches, horizontal drains, pit-bottom sumps and inpit dewatering wells where required."

Jan 1, 1980

By I. Haskett

ABSTRACT The Redwater pool, in north-central Alberta, was discovered in October, 1948, and at the end of 1950 was about 85 per cent developed. Production is from a Devonian coral limestone reef and is found at an average depth of 3,150 feet. The pool has an estimated .productive area of 37,000 acres, and a maximum oil zone thickness of slightly over 200 feet. Wide variations exist in both type and values of porosity, with the average value determined for the reservoir being 6.16 per cent. The total stock tank oil in place is about 1.24 billion barrels. The crude has a saturation pressure of 485 psig, com-pared to the original value of 1,050 psig for the reservoir, and the principal recovery mechanism so far has been the natural water drive. Cumulative production to January 1st, 1951, has been about 15.5 million barrels. These withdrawals resulted in a reservoir pressure decline of slightly over 100 psi. Predictions of future behaviour indicate that the water drive will not be of sufficient magnitude to maintain the reservoir above saturation pressure past 1953, and that, with natural depletion, the pool will be produced largely by a solution gas drive. Pressure maintenance by water injection has been considered and the possibility of raising the pressure to the original value of 1,050 psig is also discussed. INTRODUCTION WITH the discovery of the Lewduc pool, early in 1947, the Devonian limestone became the major geological formation contributing to Western Canada's rapidly growing petroleum reserves. Redwater, discovered in October, 1948, is now the largest known Devonian pool in Canada, with a recoverable reserve estimated at approximately 500 million barrels. Until recent years, the knowledge of the nature and characteristics of this type of limestone reservoir has been comparatively limited.

Jan 1, 1951

By J. Koponen, M. van de Vijfeijken, L. Bos

"The availability and reliability of large grinding mills and their Gearless Mill Drives (GMDs) are of paramount importance for the grinding process. Although GMDs have been in service for decades, and are known for their operational efficiency (reliability and robustness with reduced operating cost per ton), compared to conventional drives, in the last decade due to certain reasons some failures led to serious unscheduled shutdowns and significant insurance events.The majority of these notable ""insured"" failures have happened on GMDs installed on relatively large mills, as the financial impact of a failure is proportional to the through-put of the mill. Despite the occurrences of these events, as mining operations are driven by lower ore grades and the ability to continue reducing operating costs per ton, the trend for having larger mills is still very present and there is no reason why this trend should not continue.It is obvious that if not handled correctly, the possibility of large value GMD loss events, coupled with the continuing increase in mill size or required availability and reliability targets, could potentially lead to major conflicts as it becomes difficult for the insurance companies to judge the risk and hence may result in hesitation to insure these grinding circuits. This paper will not only describe the conflicting situation from both an insurer's perspective and from an equipment supplier's perspective, but also how these conflicting challenges can be successfully mastered. It has to be noted that not only the mining companies themselves, but also their insurance companies and the involved equipment suppliers have a common interest: to reach the highest availability and reliability in order to avoid or at least minimize unscheduled shut down times, and most importantly prevent unplanned events that result in extended production stoppages or reductions in through-put of GMD driven mills.From the very beginning onwards, the complete service concept together with emergency plans must be integrated on every level in the design of the grinding circuit. This approach must be implemented continuously and without compromises by all involved parties during all following stages, such as basic design, detail design, manufacturing, quality inspection and testing, packing, transportation, storage, installation, commissioning, operation and maintenance. The concept of formal risk analysis related to mill operations, maintenance and spare parts strategies must be an integral part of mining companies’ decisions related to the selection for installation and continued use of large mills powered by GMDs. The service concept in place for operating mills shall also have a clear focus on very early detection of any abnormalities, so that the risk can be mitigated and unscheduled shutdown times avoided. However, if a major failure occurs, then procedures and tools shall already be available in order to ensure that production impact is minimized."

Jan 1, 2012

By J. T. Sims, C. E. Karayannopoulos

Today's rare earth industry is undergoing significant and rapid evolutionary change toward greater reliability and diversity of supply, increased security of supply chains, and better price forecasting. Technology innovation is reducing rare earth production costs while decreasing the impact of producers on the environment. Advances in rare earth material science are reducing the need for relatively scarce heavy rare earths (HREEs) in high-performance neodymium-iron-boron (NdFeB) permanent rare earth magnets and opening the NdFeB magnetic market space for a broader range of downstream applications. Rare earth producers such as Molycorp are increasingly able to offer long-term supply agreements with forward price predictability, something that has not been the case for many years. All of these trends are helping to restore the confidence of customers and other stakeholders in the rare earth space. That increased confidence is likely to bolster global demand for rare earth materials and expand innovative utilization of these remarkable materials.

Jan 1, 2014

By Côme Carbonneau

The ten -year case history of La Société Québécoise d'Exploration Minière (SOQUEM) is reviewed under the headings of the company's raison d'être, objectives, policies, structure and final goal. A brief analysis of its past operations is presented: aborted efforts, findings and developments. A projection is made of the future earnings, in terms of estimated present value, of its three main discoveries - Louvem , Niobec and Selim.

Jan 1, 1978

By A. D. Fisher

This paper describes the future position of metallurgical coal, particularly as applied to Canadian reserves. Quality coking coal is declining in availability, but preheating practices may alleviate this situation to some extent. Two new processes are discussed in the paper - formed coke and direct reduction - and their coal specifications are outlined.

Jan 1, 1972

By Tim Gartner

This paper introduces a new application of a proven technology to provide dynamic, voltage regulation in underground mine electrical distribution systems. This technology acts to ?stiffen? the electrical power feeding continuous miners and generally raise and improve the voltage regulation at the continuous mining machines which may be located over long cable distances from the mine incoming electrical substation. This is extremely valuable for large underground continuous mining operations that use high power electrical mining machines fed over very long cable lengths (measured in 10s of km, from mine shaft to mine operating face). This new technology provides fast acting dynamic voltage regulation (voltage support) while starting continuous borers and extensible conveyor belts. Additionally, if the mine suffers from a lower distribution voltage due to long cable lengths, this new technology will raise the overall voltage at the mining machine, which can increased mining machine production and lead to longer motor life. The technology is based on voltage source converters operating as static VAR compensators specially packaged for the harsh underground mine environment. While static VAR compensator technology has been successfully used in utility and large industrial applications for many years (including open pit mining and arc furnaces), it has not (until now) been applied in underground mining. The paper will present the problem of poor voltage regulation in underground mines on weak electrical utility networks. It will then discuss some of the alternatives that have been used to resolve this voltage problem. It will then introduce the new technology used to solve the problem and review the issues involved in using this technology in the harsh underground environment. Finally, the paper will present preliminary performance results from an actual installation in a large underground continuous mining operation in Canada.

May 1, 2003

By R. I. Cavanagh, A J. Last

THE USE of higher grade charges in blast furnaces in the form of sintered or pelletized concentrates has been increasing rapidly. The question of beneficiation of iron ores for this purpose is therefore receiving much attention as more deposits are developed. Many iron ores may respond well to magnetic roasting procedures followed by magnetic concentration, however, in most cases other more standard ore dressing methods are competitive and cheaper. For magnetic roasting as applied to iron ore beneficiation, the present question is "Can it be economically justified in situations where it appears to produce good results?" The following collection of information on the general status and operations of magnetic roasting methods may be helpful in considering this question. Magnetic Roasting Magnetic roasting involves the transformation of non-magnetic iron oxides, hydrated oxides and carbonates by means of heat and suitable

Jan 1, 1961

By R. L. Bruening, N. E. Izatt, S. R. Izatt

"Rare earth elements (REE) are essential and unique components of many high-technology products without which functioning of modern society would be greatly impaired. Commercial deposits of REE are limited to a few geographical locations. Largely untapped sources of REE are available in endof- life (EOL) magnets, rechargeable batteries, and electronics. Presently, < 1% of REE in EOL wastes is recycled. Conversion of EOL wastes to liquid streams allows use of IBC’s Molecular Recognition Technology (MRT) process to selectively recover, separate, and purify target REE and associated metals at g/L to mg/L or lower concentration levels. The MRT process together with its applications to separations of REE and associated metals in recycling as well as in mining are described. Economic and environmental advantages of MRT are presented. INTRODUCTIONRare earth elements (REE) include the lanthanide series (La-Lu), Y, and Sc. These elements are not rare, but concentrated minable deposits are scarce (Cordier 2012; Haxel, Hedrick, & Orris, 2002). Over 95 % of the world’s supply of REE is controlled by China (Hanson, 2011a) where they are mined, processed, and the pure elements incorporated into a growing number of consumer and military products. The consumer products are marketed worldwide. Since REE are vitally important in consumer and military products, this situation has caused other nations to scramble to develop the capability to produce their own supply (Cordier, 2012).In the U. S., Molycorp has reopened the Mountain Pass REE mine in California and production has begun (Goldenberg, 2010). Development of a reliable internal source of REE is of high national priority in the U.S. (Hanson, 2011b; Hess, 2012: “Obama Announces”, 2012). These elements have in recent decades been incorporated into new consumer and military products that are essential to our economy and defense. These products range from wind turbines, high performance magnets, hybrid car rechargeable batteries, energy efficient lighting electronics, flat screen televisions, and smart phones to advanced weapons systems (Haxel et al., 2002; Levkowitz & Beauchamp-Mustafaga, 2010)."

Jan 1, 2012

By F. M. Doyle, G. Sidhu, A. J. Dussault, A. Raygani

There is a growing demand for rare earth metals for use in high strength permanent magnets, most notably Nd2Fe14B. Rare earth metals are extremely reactive, with reduction potentials around -2.5V SHE, and are conventionally produced by molten salt electrolysis. The current work was done to investigate an earlier report of electrodeposition of a neodymium ferroalloy from aqueous solution, to determine whether this approach could be an environmentally and economically competitive commercial approach for producing feedstock for permanent magnets. Such a process would be analogous thermodynamically to the Castner- Kellner process, in which aqueous sodium chloride brine is electrolyzed in cells with mercury cathodes. Metallic sodium forms an alloy (amalgam) at the cathode, thereby lowering the activity of the metallic sodium significantly below unity and making the reduction potential of sodium significantly less negative than the standard reduction potential. Here we report the effects of Nd/Fe ratio in the electrolyte, current density, temperature and two different complexing agents, glycine and cysteine, on the composition and morphology of the electrodeposits, along with current efficiency. The energy needed to produce neodymium as Nd:Fe alloys by aqueous electrodeposition was compared with values estimated for production by molten salt electrolysis and the thermodynamic energy requirement.

Jan 1, 2014

By Jiuhua Xu, Yuling Xie, Fenglei Bie, Neng Jiang

"Abstract - The Xiaoqingling Mt. area is one of the most productive gold districts in China. The gold-bearing quartz veins are controlled by a series of east-west shear zones within the Archean Taihua Group, and related to the late Yanshanian (Cretaceous) granite. The major metallic minerals are native gold, electrum, pyrite, galena, chalcopyrite and sphalerite, with gangue minerals dominated by quartz, sericite, ankerite, and calcite. The host rocks are mainly amphibolite, plagioclase gneiss, and migmatites. Principal alteration is sericitization, silicification, pyritization, and carbonization.There are four generations of hydrothermal quartz in altered rocks of gold deposits. The earliest generation of quartz, (Q1), occurs in altered amphibolite gneiss and migmatite, and typically contains fluid inclusions with halite crystals (type A) and two phases, (L+V), of fluid inclusions (type B). The salinities of type A inclusions are 32 wt% to 52 wt%, with dissolution temperatures of halite crystals being from 155°C to 465°C. The second generation of quartz, (Q2), occurs as a fine-grained aggregate associated with sericite, and has small (less than 3 µm) type B inclusions. The third generation of quartz, (Q3), occurs in mylonitic, intensively altered rocks and specially beresite (a type of rock composed of quartz, sericite, and pyrite) near the veins, and contains large amounts of CO2-rich fluid inclusions (type C-fluid inclusions with liquid CO2 and type D-fluid inclusion with high density CO2). The CO2 contents of type C range from 72.6 to 87.4 mol% in gas phases, and 35.7 to 68.3 mol% in liquid phases, based on Laser Raman analysis. The homogenization temperatures of fluid inclusion type A and C are from 215°C to 380°C, and from 210°C to 325°C, respectively. The minimum trapping pressure of fluid inclusions is estimated as 80 MPa to 170 MPa for type A, and from 57 MPa to 190 MPa for type C, which approximate to those of fluid inclusions in vein quartz.The ?18O of quartz are from 10.4‰ to 11.0‰ for Q3 of altered rocks, and from 10.7‰ to 12.8‰ for stage I quartz. The calculated ?18O of fluid inclusions varies from -1.3‰ to 6.0‰. The ?D of fluid inclusions ranges from -67‰ to -59‰ and from -81‰ to -48 ‰, respectively. It is concluded that the water in the hydrothermal fluids both reacting with wallrocks and precipitating orebodies could have been mainly of magmatic and/or metamorphic nature. However, local meteoric water might have been important in late mineralization, because of a distinct oxygen-shift toward the meteoric water. The ?34S values for pyrite of the ores range from -7.1‰ to +7.1‰, with an average of +2.9‰. Those of other sulfides (chalcopyrite, galena, and sphalerite, range from -12.5‰ to 8.3‰. The ratios of lead isotopes for galena of the ores are: 17.06 to 17.31 (206Pb/204Pb), 15.43 to 15.74 (207Pb/204Pb) and 37.58 to 38.45 (208Pb/204Pb). In summary, ore-forming fluids in the Wenyu-Dongchuang gold deposits may have originated from a mantle and/or lower crust source, and ore materials were derived from the Precambrian basement, the Taihua Group."

Jan 1, 1998

Strengthening a mine with the Power of their Employees: ?Imagine if the global economy collapses, your head office calls, and tells you to shut down for 3 months... now what do you do? ? HVC Business Improvement Initiative Why did we need help ? External Events ? How we responded ? How we worked with Westwind ? Alignment ? Priorities ? Coaching ? Focus Groups ? Innovation ? What worked / Opportunities ? Questions

Nov 1, 2011