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By A. Tylczak, C. Norman, C. Shook, S. Loif

"There are a lot of good reasons to manage energy use at mining operations. Optimizing process energy use reduces operating costs. Tracking energy use can help identify unplanned process changes or malfunctioning equipment early, which allows problems to be corrected promptly.Sacré-Davey Engineering in Vancouver has performed over 50 Energy Management studies for various industries including: mining, pulp and paper, oil and gas, etc. Energy Management programs can be used to identify energy reduction opportunities, assess project feasibility, complete equipment selection trade-offs, as well as to monitor and manage energy costs. Benefits of energy management programs are reduced energy costs, reduced maintenance, and increased plant automation. Additionally, energy management can provide access to utility incentive funding and quantify savings which can greatly improve the return on investment of potential projects.Energy management studies are funded by many Utility programs across Canada. There are various programs available for existing plants energy audits, project feasibility studies, new plant design reviews and energy monitoring and targeting, etc. There are capital incentives available which can significantly reduce payback period.This paper discusses how energy management can be used to support mill/mine operations groups, maintenance programs, as well as expansion or green field projects. This paper will also provide an overview of Canadian Utility companies programs and how they can assist mining companies.IntroductionThere are a lot of good reasons to manage energy use at mining operations. Optimizing process energy use reduces operating costs. Tracking energy use can help identify unplanned process changes and identify malfunctioning equipment early, which allows problems to be corrected promptly."

Jan 1, 2015

By André de Albuquerque Vicente

O valor do PREN da liga pode levar a uma previsão equivocada da resistência à corrosão por pite pois, caso haja um desbalanceamento das frações volumétricas da ferrita d e da austenita, as composições químicas das fases poderão ser muito diferentes daquela da liga. Neste caso o PREN de uma das fases pode ficar abaixo do PREN da liga. Caracterizou-se três chapas de aços inoxidáveis duplex laminados com diferentes PRENs: UNS S32304 (Lean Duplex), UNS S31803 (Duplex) e UNS S32750 (Super Duplex). Várias técnicas complementares de análise microestrutural foram utilizadas, tais como de espectrometria de emissão ótica, microscopia óptica e microscopia eletrônica de varredura com EDS acoplado. Realizaram-se análises metalográficas quantitativas para a determinação das frações volumétricas de ferrita d e da austenita e análises químicas semi-quantitativas das fases presentes utilizando-se um MEV com EDS acoplado.

Oct 30, 2017

By J. B. Dilworth

I. INTRODUCTION. THE purpose of this paper is, first, to give a general account of a little-known coal-district of SE. Kentucky, its topography, drainage, and mineral resources, for those who may be interested in its economic development; and secondly, so to describe the geologic features of the field as to furnish available data to those engaged on the broader problems of Appalachian coal-geology. The data from which the major portion of the paper has been prepared were obtained, in professional investigations for private individuals and corporations, within the last decade. The area under review, defined by a heavy line on the map, Fig. 1, lies between Little Black and Pine mountains, and extends from Harlan on the west to a N-S. line crossing Looney creek 3 miles from its mouth on the east. This area can be divided for description into a Western and an Eastern Division. The character of investigation pursued in the Western Division, below Fugitt creek, was very different from that employed in the Eastern. In the former, only a rapid reconnoissance was attempted : such coal-openings as had been made by prospectors or by citizens in obtaining fuel were visited, their sections measured and, in many instances, sampled. Elevations were obtained barometrically and approximate locations sketched on a small-scale map. In a field where the coals are so well opened, the reconnoissance method gives a very fair idea of the number and character of the principal beds and their relative positions, and affords much evidence for their correlation over wide areas, without permitting the more refined work required to discover all the seams of the measures and to determine the details of geologic structure.

Feb 1, 1912

By D. R. Wilburn

The worldwide budget for nonferrous, nonfuel mineral exploration was expected to increase by 58 percent in 2004 from the 2003 budget, according to Metals Economics Group (MEG) of Halifax, Nova Scotia. The increase comes two years after a five-year period of declining spending for mineral exploration (1998 to2002). Figures suggest a subsequent 27 percent increase in budgeted expenditures from 2002 to 2003. For the second consecutive year, all regional exploration budget estimates were anticipated to increase. The worldwide budget for gold exploration achieved about 50 percent of the total amount budgeted in 2004.This was 68 percent, or US$715 million, higher than the reported 2003 budget. The 2004 worldwide exploration budget estimates for copper increased by 70 percent, orUS$237 million, to US$577 million from the 2003 budget. The budget for nickel exploration increased 52 percent, or US$89 million more than in 2003. The 2004 exploration budget for other mineral targets (primarily cobalt, heavy minerals, industrial minerals and silver) increased114 percent, or US$118 million.

Jan 1, 2005

By B. P. Nutter, M. Lebourg, J. A. McAlister

The Multi-Flow Evaluator (MFE) is a new system of tools providing an original approach in drill-stem testing. It improves control during the testing operation and gives a more accurate evaluation of the fluid recovered while providing additional pressure information for reservoir analysis. The tools are operated entirely by up and down motion of the drill stem. This up and down operation provides a positive means of control and offers easily observed surface indications of tool operating position. An unlimited number of shut-in and flow periods may be taken with this tool while in the hole. The key to the success of the MFE system of tools is the safety seal packer. Until this development, operation of the tools by up and down motion only had proven unreliable. The success ratio of the MFE now exceeds the ratio achieved by conventional tools. The equipment includes a 2,750-cc chamber in which a representative sample of the flowing formation fluid is trapped at the end of the last flow period and brought to the surface under pressure. The sample can be evaluated at the wellsite or transferred under pressure for laboratory analysis. The sampling feature of the tool allows a sample to be obtained from a reservoir which has suffered minimum influence from production. A representative sample can be obtained for laboratory or empirical analysis by employing a testing technique to minimize drawdown during flow periods. Interpretation methods to take advantage of this additional information are presented and supported by actual field examples. INTRODUCTlON The Multi-Flow Evaluator (MFE) represents the most recent technical advance in formation testing. Drill-stem testing techniques prior to the MFE have been limited in three areas—(1) operaiion, (2) recovery analysis, and (3) reservoir analysis. The tools in the MFE system allow maximum control during testing and provide test information superior to that obtainable with conventional tools. The system of tools and the operation procedures are described to illustrate the mechanical advantages over present tools. Methods of pressure build-up and fluid

Jan 1, 1966

The mineralogy and microstructure of mattes from the nickel flash smelter at Kalgoorlie, Western Australia, have been studied. The flash furnace matte consisted mainly of an intimate mixture of pentlandite and heazlewoodite with some nickel metal. The electric furnace matte was mainly an iron-nickel alloy with subsidiary pentlandite while the converter matte consisted mainly of heazlewoodite with crystals of nickel metal.

Jan 1, 1977

By Meghan McGrath

Third generation advance high strength steels with microstructures of acicular ferrite and retained austenite were investigated and meet mechanical property goals. A good combination of strength and ductility were achieved with duplex ferrite and austenite microstructures where cementite formation was suppressed. Transformation induced plasticity (TRIP) behavior produced rapid work hardening. The mechanical properties of two hot-rolled steels with duplex microstructures were compared and had the following compositions: (1) Fe-0.14C-13.87Mn-1.42Si-3.51Al; and (2) Fe-0.06C-14.2Mn-1.85Si-2.38Al. These steels were cast, homogenized, and hot rolled at 900ºC to obtain a refined microstructure with ultimate tensile strengths and elongations to failure of 865 MPa and 39% and 1,217 MPa and 28%, respectively. The amount of metastable austenite in both compositions decreased after tensile testing from 58% and 28% to 6% and 0%, respectively. Microstructures were characterized using optical microscopy, scanning electron microscopy (SEM), and x-ray diffraction.

Jan 1, 2010

By D. H. McCain

Through a unique partnership between the Colorado Mine Safety and Training Program (CMSTP), the Colorado Rock Products Association (CRPA) and the Higher Education and Advanced Technology (HEAT) Center, a video packed, dazzling CD-ROM training program was developed for new miners entering the aggregate industry. Why this product was developed, and why the aggregate industry, will be discussed along with the challenges faced throughout the project. Cooperation from every one involved including MSHA made this the product of which all other training materials in the mining industry will be measured against in the 21st Century. This product's versatility and wide application makes it a tool that is as critical to a mine's success as any earth moving machine. Developed with both state and federal grant moneys allows this product to be affordable to small operators and independent contractors. The quality of this two CD-ROM set rivals any commercially made CD-ROM training.

Jan 1, 2001

By Julver Álvarez

El presente trabajo describe el comportamiento estructural y mineralización del estaño-cobre en la mina San Rafael, Puno. En este sentido, las pizarras de la formación Sandia del Ordovisco Superior, por metamorfismo de contacto con el intrusivo, han sido transformadas a hornfels, que junto a las cuarcitas se presentan algunas veces como una cubierta superficial sobre el intrusivo. Asimismo, los intrusivos y las pizarras son favorables para la mineralización de estaño, aunque los cuerpos del mineral son más definidos y persistentes en el intrusivo.

Sep 13, 2001

By L. V. Clark, Arthur La Motte

"INTRODUCTION The U. S. Bureau of Mines in 1930 and 1931 made a study of the properties and characteristics of liquid-oxygen explosives (L.O.X.) at the request of one of the largest users, in order to determine and eliminate the hazards attending its use.This report deals with the examination of absorbents for L.O.X. to (1) determine their most desirable and most undesirable characteristics, (2) to find ways and means of desensitizing absorbents to mechanical shock, and (3) to determine the effect that such desensitization of absorbents has on the explosive Characteristics of L.O.X.ABSORBENT MATERIALS The absorbent used in driving the Simplon Tunnel, the earliest project in which L.O.X. was used, was composed of crude petroleum, soot, and kieselguhr. During the World War, powdered cork, soot, sawdust, powdered straw, or other similar powdered materials were mentioned in the German military instructions for use of ""liquid air"" explosives. At that time the common types of absorbent, materials were compounded ones containing the above ingredients as well as kieselguhr, paraffin, gas oils, charcoal, bituminous coal, etc.Kuryla and Clevenger4 investigated absorbents of the above type and made the following statement concerning them:"

Apr 1, 1932

By Hewitt Wilson

Until recent years the term "whiting" was applied exclusively to the water-ground chalks of certain north European countries. In many industries these are still considered superior to the whiting made from domestic limestone and marble. However, the latter material has replaced much of the European whiting in the American market, largely due to improvements in grinding and classification by American manufacturers.4 To encourage the domestic industry, the Bureau of Mines in 1931 undertook a study of the preparation of whiting from American raw materials and a comparison of the finished products with European whitings.

Jan 1, 1937

By D. S. van Vuuren

Over the last 60 years many different processes were conceived to reduce the cost of titanium produced by the Kroll process. However, success eluded all previous efforts, which were consequently terminated in periods of economic downturn. Recently, the grow thin demand for titanium and the high cost of producing the metal again sparked renewed attempts in various parts of the world to replace the antiquated Kroll process with a more efficient route. The different options to produce titanium are reviewed, classified and evaluated in terms of the fundamentals underlying the technologies, and it is shown that the options considered to be the most likely to replace the Kroll process, are continuous processes to reduce TiCl4 metallo-thermically to titanium powder. Of these, continuous magnesio-thermic reduction of TiCl4 would conceptually result in the lowest-cost and highest-value product. However, when considering by-product salt removal from the titanium product and recycling of the salt as well, sodio-thermic reduction of TiCl4 is better.

Jan 1, 2009

By Carlos Alberto Alves Nunes Filho

Este trabalho tem o objetivo de traçar o panorama atual das exportações de minério de ferro e a logística integrada desde a jazida, extração, empilhamento e transporte para uma área de armazenagem próxima ao Terminal Portuário do Pecém para posterior embarque no navio e entrega ao cliente final. Optou-se por uma pesquisa exploratória descritiva para identificar as dificuldades na logística que dificultam o escoamento do minério pelo Terminal. Utilizando dados coletados de empresas que atuam na região e que utilizam o Porto do Pecém como saída de sua produção, demonstrando também os estudos de custos e de produção, tipos de modais mais utilizados os navios e suas especificações que fazem o transporte do minério a granel, os equipamentos pertinentes a operação portuária de embarque, bem como os tipos de minério existentes e os que são encontrados nas áreas de mineração no Estado do Ceará e as suas características. O Terminal Portuário do Pecém possui uma estrutura de acostagem preparada para esse tipo de operação proporcionando facilidades aos exportadores.

Aug 17, 2017

A modified liquation technique was developed for recovering tin from tinhouse scruff metal or hardhead containing about 10 per cent iron and 15 per cent occluded flux, palm oil, and moisture. This was effectedby heating the scruff metal to 950°C followed by rapid cooling to suppress the formation of FeSn2 and FeSn, and then subjecting it to the ordinary liquation and drossing processes of refining. By this method it was possible to recover about 83 per cent of the original tin content and, with subsequent smelting of the irony drosses, an overall recovery of 92 per cent was obtained.

Jan 1, 1969

By A Watson

We tend to overestimate the volume of water used to process ore and the evaporation from tailings and heap leach stockpiles. During mine operation, a significant portion of the water collected from onsite water management systems is consumed and recycled by ore processing and lesser portion discharged to the environment. When mining and processing cease, however, the mine site water balance is altered and the real effort and cost associated with managing and disposing of excess mine-influenced water becomes evident. As these flows can no longer be recycled and may not be suitable for discharge to the environment, the cost of dealing with them can comprise a significant portion of the post-mining liability. The problem of dealing with large volumes of mine affected water has the potential to become worse in the future due to the established trend of lower grades which require more water per unit of mineral processing. As a result, future mines may be expected to have greater water needs and problems than we experience today.This paper discusses various aspects about how water usage changes when a mine transitions from operation to closure based on observations and numerical simulations of made with site-wide water balance models. The intention is to provide general considerations for mine operations in planning for end of mine life and post-mining care and maintenance.

Jan 1, 2009

By R Lethlean

The mining industry in its drive to optimise equipment use and minimise cost simply to remain profitable in an uncertain commodity market needs to develop a greater understanding of equipment capabilities and cost. The factors influencing mobile equipment fleet cost and performance commence at the time of mine planning and continue to exert an influence over the life of the mine. These factors must be understood at the early stages of any operationÆs planning process as they continue to impact both positively and negatively on fleet performance and operating cost throughout the life of the mine. The key factors examined in this paper include: grades; rolling resistance; fragmentation and truck loading.

Jan 1, 1998

By J. Engels

CODELCO is considering the implementation of high-density tailings management at the Chuquicamata mine in northern Chile for its long term disposal plan. To achieve this, CODELCO commissioned the design, construction, and operation of a 70 t/d pilot plant, fed by existing tailings. The testing programme was completed in May 2011, and consisted of laboratory rheological and characterization assessments, pipe loop testing, beaching trials, and analyses of deposition behaviour for solid contents ranging from 57?68% (w/w). This paper describes the characteristics of the pilot plant, the testing programme, the beach trial analyses, and the resulting beach profile predictions based on the stream power theory. CODELCO also used other predictive beach slope methods, such as the equilibrium slope concept, which are not discussed in this paper. The final beach profile for design will be selected after an expert analysis of all methods has been completed.

Jan 1, 2012

By G. L. Oldwright, F. K. Shelton, W. E. Keck

"INTRODUCTION Zinc must be of high grade to satisfy the present demand. Even when the amount of premium paid is small, the purer metal as the buyers' preference. The following specifications for spelter were taken from the American Society for Testing Materials for 1927, Part I, pane 524. (The specifications for 1930, p. 582, are tile same.)Another specification for zinc of a much higher grade than any of the above has been established lately by the same society. The committee on zinc die-casting (Proc. Am. Soc. Test. Mat., vol. 31, 1931, p. 263) reached the following, conclusions: I. ""That the purest of zinc is necessary to produce stable zinc-base die castings, and as a result requested specifications for zinc spelter .with total impurities not over 0.02 percent."" Their tests showed that the die castings made of the purest zinc had the least elongation and the greatest tensile strength, and exhibited the least changes with temperature.Still more far-reaching claims are made for the properties of zinc containing over 99.99 percent metal. Zinc foil, for instance, may someday be made as a common commercial product. It would seem likely that the demand for zinc of high grades rill continue and that even purer varieties may be desired. This demand fits in with the modern trend in manufacturing plants of reducing the number of variables to a minimum by using pure materials, and of controlling the processing of metals during their various stages of fabrication by mechanical means instead of by expert laborers."

Jun 1, 1933

By M. P. Hay

"For a model to be successful it must address the concerns and needs of a target audience. Further, the model must demonstrate the same patterns of behaviour as the real system, and need only be complex enough to meet this objective. If the model is too complex it can become unusable to those who need it most.With this in mind, SUPASIM has been developed for the practical metallurgist requiring only laboratory flotation rate data as input. Some 35+ successful plant simulations have been completed since 1985. The approach of SUPASIM is to characterise an ore, organise information in an understandable way and add structure to the complex flotation situation and hence support the metallurgist to interpret the relationship between variables and optimise the flotation process.The paper describes the basis on which the model was developed and sets out to provide an insight into interpreting laboratory flotation kinetics and their physical meaning in a production plant and the influence floatable gangue has on float performance and plant design. A case study illustrates how the ratio of slow floating mineral to gangue can influence circuit design and improve recovery on a plant scale.INTRODUCTIONThere is an enormous amount of useful data in the results of a laboratory scale rate test. Each variable of fraction and rate, for mineral, metal and gangue has a physical meaning in the plant. The link between float kinetics and the plant in respect of recovery, grade, pulp density, pulp flowrate, residence time, number of stages of cleaning and circuit configuration has been established by the author in the process of developing SUPASIM."

Jan 1, 2005

By Rocky (Yaokun) Wu

This paper introduces the development and application of a new cable anchor - Cable-Lok for pre-stressed cable bolting in mines. Cable-Lok is a spring-loaded cable anchor suitable for the drill hole diameter of 50 and 65 mm (2" and 2.5") in medium soft rock to hard rocks. The cable anchor is automatically set on installation and the cable can be tensioned immediately to provide active and primary support throughout its length. Post-grouting can be conducted independently. In comparison with the conventional cable bolting, Cable-Lok anchor will greatly speed-up the cable bolting circle and decreases the cost of cable bolting. Cable bolting anchored with Cable-Lok anchor has wide application in mines, e.g. pre-stressed cable bolting in large span drifts and intersections for permanent rock support, or in hanging walls or stopes for temporary support, or cable lace anchoring etc. This paper introduces the principle of pre-stressed cable bolting and the specifications of the Cable-Lok anchor, presented the testing results in laboratory and the application cases in mines.

Oct 1, 2010