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By John Vergunst

"This paper traces the development of Ontario 's cap lamp standard. Over the years, numerous Coroner's Juries investigating fatal mine accidents have made recommendations with respect to underground lighting. As well, recommendations to improve mine lighting have been made by two Commissions, investigating mine safety in Ontario.During the past few years, the performance of any cap lamp worn by miners involved in serious accidents, have been measured by the Mining Heal/h and Safety Branch. Large variations in light output were found between and among cap lamp types. These variations have been attributed to the lack of quality control on the bulbs, design of the cap lamp head piece and in some cases, poor maintenance.In 1986, a series of underground tests were conducted to establish the minimum light output from cap lamps required to visually identify loose ground. The results of these tests indicated that a cap lamp should produce a minimum peak illuminance of 1500 lux measured at 1.2 metres from the light source. On May 30, 1987, Ontario became the first province in Canada to legislate the minimum amount of light required to visually assess ground conditions. INTRODUCTIONPoor lighting has been identified as a factor which can contribute to mining accidents. Over the past decade, several Coroner's Juries as a result of inquests into mining fatalities, have recommended improved lighting in mines.The Joint Federal-Provincial Inquiry Commission into Safety of Mines and Mining Plants in Ontario, was appointed to report upon the adequacy of existing arrangements and practice s that may affect safety. This Commission completed their report in April 1981, and recommended that inadequate lighting be investigated as a possible cause of all reportable underground accidents, and that a comprehensive research programinto mine lighting be undertaken.In response to the first recommendation, the Mining Health and Safety Branch of the Ministry of Labour, hereafter referred to as the Branch, initiated a program to measure lighting levels in all fatal accident investigations where inadequate lighting was a possible factor."

Jan 1, 1989

By Floyd R. Anderson

Noise control of existing pneumatic drills is difficult and runs into cost, performance and weight penalties. A need exists for a start-from-scratch approach for quiet pneumatic rock drills. The designs based on Leavell Principles which has been successfully used in demonstrating a quiet and vibration free paving breaker, is the concept chosen here. This report shows the feasibility of a quiet stoper for drilling roof bolt holes in coal mines. The work is directly applicable to pneumatic percussive rock drills. The report shows an oscillator based on patented Leavell concepts which results in a vibration free tool and noiseless exhaust. Dynamics of the oscilator is analyzed. Independant rotation of drill rod is provided by an air motor (screw expander) and flushing of cuttings is accomplished by an air ejector in a compact lower housing. The feasibility of no exhaust noise, low drill machine noise, and vibration free casing is discussed.

Jan 1, 1977

By X. Xu

This paper presents the research on comprehensive recovery of copper, gold, silver and iron from tailings from high-intensity magnetic separation in Tonglushan Mine. By comparison of experimental results of three flowsheets?regrinding of tailings-conventional sulphidizing flotation, water heating enhanced sulphidizing flotation and acid leaching-sulphidizing precipitation flotation, it is concluded that regrinding of tailings-conventional sulphidizing flotation flowsheet has the best economical and technical performance and practicability. Regrinding and using the mixture of sodium hydroxamate and sodium xanthate are two of the notable technical characteristics of this best flowsheet. The system for comprehensive recovery of tailings has been put into production. It not only can recover the valuable minerals from tailings in Tonglushan Mine, but also can reduce the environmental pollution, resulting great economic and social benefit.

Jan 1, 2014

By Gerald Whittle

What is Enterprise Optimization? Releasing value through better planning decisions: Philosophy, Methodology, Software The key to 5% -35% increase in enterprise value (NPV) The culmination of 25 years development in optimization for the mining industry ?Jeff Whittle Simultaneously optimizing: ?all steps in the value chain ?all assets in the enterprise portfolio ?all periods together

May 1, 2010

By Robert Torbin

The objectives of the Continuous Shaft Lining (CSL) System are to reduce the costs, safety hazards, and time currently required in lining mine shafts with concrete. The CSL will line machine bored shafts downward from the shaft collar on a continuous basis using an inverted, pressurized slipforming technique. The technique for slip-forming downwards has been demonstrated and refined under this program. The approach taken involved laboratory scale testing of key features of the CSL concept. These feature tests included concrete distribution, concrete sealing, concrete slipforming and development of a reliable concrete mix. Based on these results, a full scale above-ground test facility and CSL were designed and fabricated. The objectives of these tests were to demonstrate the viability of the basic concept; to establish operating limits; and to provide input data and information for the design of a second generation shaft lining system. The results of the program have led to a CSL design and operational philosophy which will need to be tested in an underground environment before industry will accept the technology. However, the next generation CSL promises to meet all the original program technical objectives.

Jan 1, 1983

By Steven Hart

In September 2009, Newmont began the commissioning of a 3 stage crushing and milling circuit at its Boddington Gold Operation in Western Australia. The Boddington ore has been recognized as one of the hardest and most abrasive ores treated to date and this played a pivotal role in the selection of crushing and HPGR technology for this operation as opposed to the more conventional SABC circuit. This paper will examine the scale up from laboratory to pilot plant and full scale operation of the crushing circuit. There have been many challenges to overcome in the first 18 months of operation; however, the HPGRs have in general met design expectations and performance is expected to improve further with ongoing design changes

Jan 1, 2012

By Filipe Sathler

O projeto CR298 se iniciou no final do segundo semestre de 2014 quando o Coque Rate (CR) médio era de 351,0 kg/t. A meta definida foi de atingir média mensal de CR de 298 kg/t em dezembro de 2016, permitindo aumento de produção com alta taxa de injeção de carvão PCI, porém, com baixo Fuel Rate, garantindo competitividade de mercado. Sendo assim, foi desenvolvido e divulgado um novo modelo mental de operação, processo, manutenção e gestão, envolvendo toda a área de Redução, Utilidades e Aciaria. Várias premissas técnicas foram estabelecidas com um plano de ação detalhado para garantir estabilidade no processo dos altos fornos de forma a obter este resultado. A meta foi atingida antes mesmo do planejado: CR 291,3 kg/t em Maio de 2016 e em 2016 a média anual foi de 297,0 kg/t, com Fuel Rate de 484,4 kg/t.

Oct 30, 2017

By John G. Henning

Unplanned ore dilution has a direct and large influence on the cost of a stope, and ultimately on the profitability of a mining operation. This paper presents results of a study on the influence of a variety of factors on ore dilution in a blasthole stoping environment. A series of 3-D numerical models were developed and analyzed to examine the effect of mining depth, stope geometry and stope setting within the orezone extraction sequence. To quantify modelled ore dilution from the three-dimensional simulations, the ore Dilution Density (DD) is a term introduced in this study to denote potential hanging-wall overbreak. It was found that hanging-wall overbreak is not significantly influenced by depth alone, and that stopes with large or small axial ratios are more stable than large rectangular stopes. It was also demonstrated that, in addition to stope dimension, the amount of unplanned dilution differed according to stope type. Five stope types were identified, based on their position within a tabular blasthole mining sequence. The methodology presented in this paper can be adopted to develop mine-specific design tools for the estimation of ore dilution associated with a proposed mine design. This can prove extremely helpful in the process of underground mine planning and optimization.

May 1, 2007

By R. E. Robinson

I shall present a concept for the development of the resources of this country and its neighbours that repre¬sents a fantastic challenge to our scientists and entre¬preneurs. This concept offers prospects of development that must make our previous achievements seem equivalent only to the first act in a drama enacted on the stage of Southern Africa. I hope to illustrate how, in Act Two, chemistry will play a dominant role, and chemists and chemical engineers will be among the principal actors.

Jan 1, 1980

By Frank E. Williams

Nuclear detonation data were accumulated, studied, and evaluated by the Bureau of Mines to visualize how nuclear explosives might be used in a shale?-oil industry, The evaluation shows that the Green River Formation at the semi-isolated locale of Piceance Creek Basin, in northwestern Colorado; is thick and widespread enough to warrant consideration of nuclear mining in lieu of conventional methods, Because cost data for nuclear explosions are limited; cost comparisons are made largely by assumptions. Also described are the history of the shale-oil industry, the geology and size of oil-shale resources; and conventional mining methods and processing technology.

Jan 1, 1969

Solid. dense, air-cooled slag can fulfil most, if not all, the functions of natural stone for civil engineering purposes. The value of pumice, also, has long been appreciated, and processes for the manufacture of similar synthetic material for light-weight concretes and insulating fills have been developed in past years.Foamed slag is, in effect, blast furnace pumice and is often referred to on the European continent as metallurgical pumice. It is made by the treatment of molten blast furnace slags with a critical quantity of water during which process the slag cools and expands into a sponge-like mass. The connection between foamed slag and air-cooled slag is also considered and a basis for density control given.All blast furnace slag cannot be foamed to give a product which would comply with B.S.S.877; 1939 Foamed Blast Furnace Slag. A large proportion of the total output of molten slag lacks the necessary inherent properties. This investigation attempts to discover the conditions necessary for the production of foamed slag capable of meeting the British specification.EARLIER WORKIt was generally accepted (Parker, 1951; Gallai-Hatchard, 1955) that the spongy structure of foamed slag was caused mechanically by steam trapped in the slag when it was poured into water. It was assumed that slags which would not foam would not trap steam, because their viscosities and surface tensions were unsatisfactory, on account of temperature and/or composition. The earliest systematic investigation was made by Frisak (1923) who attempted to establish a limiting chemical composition for foamable slags. He decided that foamable slags covered most blast furnace slag compositions on the basis of silica, alumina, and lime, and further "that the replacement of lime by magnesia up to 15 per cent has no noteworthy effect on foamability, that moderate quantities of alkalis are not deleterious, that sulphur raises the foamability and that MnO is only deleterious in the presence of 1...

Jan 1, 1963

By Rosa Malena Fernandes Lima, Kerollan da Silva Ramos, Joyce de Assis Silva, Geriane Macedo Rocha

This study evaluated the effects of collector type amide-amine compared with those of conventional etheramine acetate (both cationic collectors) on the surface properties of quartz and hematite. An examination of certain properties of the reagents indicated that the new collector amide-amine has CMC (critical micelle concentration) and pKa values (100 mg/L and 8.2, respectively) significantly lower than those of etheramine (800 mg/L and 9.4, respectively). Microflotation tests showed that the recoveries of quartz with amide-amine in all the concentrations tested were higher than those with etheramine. This is attributed to its lower CMC and pKa values. The selectivity window between quartz and hematite flotation using amideamine was higher at pH 10.5 (approximately 80% for 5 mg/L). Therefore, the use of starch is not necessary in siliceous itabirite flotation by amide–amine collector. Zeta potential measurements and infrared spectra reveal that the adsorption of amide-amine collector on quartz surface occurs mainly by electrostatic attraction. Considering the better collectability of amide-amine for quartz flotation and lower adsorption affinity for hematite surface than etheramine, the amide-amine is a promising collector to be used in reversal iron ore flotation.

Jul 30, 2021

By C. Steve Albrecht

The primary objective of this study is to "evaluate the influences of different equipment systems on prime farmland subsoil compaction due to surface mining in the Midwest." The study is centered on four mine sites each utilizing a different combination of equipment for soil removal and replacement. Subsoil compaction is the primary focus of this research effort. Primarily owing to physical location, it is difficult to alleviate the increased compaction directly below the topsoil in reclaimed soils. Different equipment combinations cause varied effects when soils are replaced during surface mining activities. By collecting field data within a statistical framework, the effects of different equipment combinations on subsoil compaction can be evaluated and conclusions drawn. This research effort evaluates a comparison of natural and replaced soils by moist bulk density data. This comparison centers on changes in bulk density and texture to a depth of 48 inches. For each study site a complete case study is provided for use in data correlation and interpretation. Basis for this research effort centers on four (4) major experiment designs: o Comparison of soil bulk density values for three distinct equipment systems evaluated on the same general soil types (i.e. scrapers, bucket-wheel excavators and end-dump haulback); o Evaluation of the effects of soil replacement in repeated lifts using scrapers; o Presentation of bulk density values representing soil compaction for four (4) equipment systems (i.e. bucket-wheel excavators, draglines, scrapers and end-dump haul back) on four separate mine sites in the midwest; o A prediction analysis model is developed for subsoil bulk density following reclamation based on equipment characteristics and a statistical evaluation of texture. The soil data base of information includes data from the 1982 Bureau of Mines study entitled, "Impact of Surface Mining on Soil Compaction in the Midwest" as well as data from this research project. The final report is synthesized through an analysis of field data, statistical analysis and literature review. The final report focuses on the interpretation of results for practical application by government and industry.

Jan 1, 1984

By W. J. Kroll

This report on the bibliography of zirconium has been confined to those publications and patents that appear to be useful in the commercial development of the metal, both the malleable and the nonmalleable. The methods of production have been stressed and special attention has been given to the alloys. Compounds of importance, like the oxide and chloride, for the manufacture of the metal or of the alloys have been considered. The use of the oxide in refractories anal in the glass and porcelain industries has been omitted. The present survey is critical; that is to say, an attempt has been made to evaluate the effectiveness of suggestions made in the literature. The exhaustive work of Marden and Richy, Bureau of Mines Bulletin 186, published in 1921, has been taken as a base to start from with the intention of bringing the subject up to date with material published in the last 24 years. During this time there was considerable 'advance in the preparation of the metal and Its alloys, and in the development of new uses. On the other hand, there was little progress in the methods of decomposing the ores, so that the chapter on this latter phase is necessarily short.

Jan 1, 1946

Comparative Studies on Balls Versus Spheroidal Tetrahedrons Working Media to Ore Grinding in an Industrial Drum Mill

Sep 13, 2010

By A. Takala, H. Cline, D. Girard

"This article describes the project development and successful implementation of a particle sorter at the Kensington mine. The Kensington underground gold mine and associated milling facilities are located within the Berners Bay Mining District on the east side of Lynn Canal about 45 miles north-northwest of Juneau, Alaska. The paper describes the project from concept, through the development phase, including test work confirming feasibility, to a discussion of operational data and includes shared experiences from operation and maintenance. The project has proven successful in recovering gold that was previously lost to the waste dump and has already resulted in a positive return on investment. The payback was achieved in less than one year.INTRODUCTION The first paragraphs of this paper describe Coeur Mining and the Kensington Mine, its history, geology, mining operation and mill. The second part of this paper gives a quick introduction to sensor-based sorting in general and X-ray transmission sorting (XRT) in particular. This article does not cover costs or economic impacts apart from the pay-back period for the investment at Kensington. Interested readers find more in information on this in the literature (Kleine & Wotruba, 2010; Robben, 2013). Since the publication about XRT sorting at TGME in Pilgrim’s Rest (Kleine, Riedel, Ketelhodt, & Murray, 2010), this is the first time that a comprehensive data set on gold ore sorting using XRT is published. Following chapters highlight the aim of the project for Coeur Kensington, project development through testing and operation before concluding. ABOUT COEUR MINING’S KENSINGTON OPERATION Coeur Mining is the largest U.S.-based silver producer and a significant gold producer with five precious metals mines in the Americas employing approximately 2,100 people. Coeur produces from its wholly owned operations: the Palmarejo silver-gold mine in Mexico, the San Bartolomé silver mine in Bolivia, the Rochester silver-gold mine in Nevada, the Kensington gold mine in Alaska, and the Wharf gold mine in South Dakota. The Company also has a non-operating interest in the Endeavor mine in Australia in addition to royalties on the Cerro Bayo mine in Chile, the El Gallo complex in Mexico, the Zaruma mine in Ecuador, and the Correnso mine in New Zealand. In addition, the Company has two silver-gold feasibility stage projects—the La Preciosa project in Mexico and the Joaquin project in Argentina. The Company also conducts ongoing exploration activities in Alaska, Argentina, Bolivia, Mexico, and Nevada. The Company owns strategic investment positions in several silver and gold development companies with projects in North and South America."

Jan 1, 2017

By Witold J. S. Ostrowski

The shaft structure being part of an underground mine, depends on programned functional duties, and on geological and hydrological conditions. The majority of Canadian metal mine shafts are in hard competent igneous rocks, which are in an elastic state of equilibrium around the excavation. Others penetrate soft sedimentary or very weak water-bearing rock formations in which the equilibrium varies from plastic to hydrostatic. Knowledge of how to interpret the underground conditions, determine acting forces and design proper structures is essential for the production and safety of the future mine.

Jan 1, 1973

By Michael J. Rinker, P. A. Tibble, M. Wiseman, R. V. Nicholson

Tailings, from an active copper-zinc operation, containing about 10% sulphur were investigated to assess the onset of acid production and potential lime requirements for treatment of drainage. Oxygen consumption rates were measured over two years to verify spatial and seasonal variations in sulphide oxidation rates. Shallow cores were collected to assess the quality of tailings porewater and to characterize solids that had been subjected to oxidation and depletion of neutralization potential (NP) for several years. Oxygen consumption data were used to quantify rates of NP depletion and onset of acid drainage from the near- surface tailings. Based on measured oxygen consumption rates and identification of NP remaining in the tailings, future lime use in the treatment plant was expected to rise significantly without mitigation. Geochemical modeling calculations were calibrated with observed oxygen consumption rates and the model results agreed well with actual lime use in the waste water treatment plant during operations. The modeling also demonstrated the benefits of lower lime demands and treatment costs after closure as a result of construction a soil cover on the acid generating tailings.

Jan 1, 2000

By Donald F. Hammer, Donald W. Peterson

The Magma mine at Superior, Arizona, has produced over 13 million tons of ore yielding 1.5 billion pounds of copper. It is a mesathermal deposit, and, although the bulk of the ore has come from the Magma vein, most of the recent production has come from replacement deposits in limestone. The mine lies in a Precambrian and Paleozoic sequence of rocks that includes schist, diabase, quartzite, shale, and limestone; nearby, these rocks are intruded by igneous bodies of Mesozoic age that were probably the source of the ore-bearing fluids. Locally, these rocks are overlain by Cenozoic volcanic rocks and conglomerate. Layered rocks at the mine dip eastward about 30°. The area is extensively faulted, and surface faults are grouped into an earlier east-trending set and a later northtrending set. An additional set of diagonal faults that trends northwest and northeast is recognized underground. The east-trending Magma vein-fault, with its splits and branches, is the principal mineralized structure of the district. The bulk of the ore occurs in large ore shoots that plunge steeply westward and are sporadically connected by irregular ore shoots dipping gently eastward. The main ore controls apparently are selective zones of permeability related to the transverse faults. A bed of crystalline limestone near the base of the Martin Limestone (Devonian) is the host for the replacement ore bodies-discontinuous tabular pods dipping eastward parallel to the bedding. Selective permeability is again the apparent ore control, caused both by local hydrothermal solution of limestone and by deformation along faults. The principal copper minerals in the vein are chalcopyrite, bornite, enargite, tennantite, chalcocite, and digenite; these minerals vary in abundance according to a distinct zoning pattern. The upper part of the mine yielded considerable zinc as sphalerite, and the oxidized zone was rich in silver. The chief gangue minerals are pyrite, quartz, and hematite. In the limestone replacement bodies, chalcopyrite and bornite are the chief ore minerals.

Jan 1, 1968

By C. O. Stee

Introduction The property of Siscoe Gold Mines, Limited, is located on an island of three hundred and forty acres in lake Kienawisik, about fifty-two miles east of Noranda and forty-three miles south of Amos, Quebec. Lake Kienawisik is a part of the Harricanaw drainage system and is crossed by the main line of the Canadian National railway at Amos. This waterway is navigable for boats with a draught of six to eight feet. Diesel engines have been the source of power at the property since milling operations were commenced in January, 1929. The power plant as first designed and built was for a milling capacity of 100 tons. Two Polar-Atlas units, each of 200 h. p., comprised the original installation. With the growth of the 'mine, more engines were added until, at the present time, there is installed at the Siscoe what is rated the largest Diesel plant at any mining property in Canada. Definition of a Diesel 'The Diesel engine is an internal combustion engine which works with liquid fuel introduced after, and independently of, the air charge at a time when communication between the cylinder and the outside atmosphere is cut off, and which ignites the fuel by compression-beat and stored combustion-heat unassisted by heat sources outside the cylinder itself while the engine is in stable operating condition"(1).

Jan 1, 1934