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By Fabien Miller

Automation technologies are increasingly envisaged to improve underground mining productivity. However, the technologies need to be used and adopted gradually in order to get the best benefits. This paper presents the technical and operational aspects of autoguided production vehicles at Brunswick Mine. During 2001 Noranda?s Brunswick Mine has successfully commissioned an automated haulage zone where two optically guided trucks transport ore from a remotely operated chute to two orepasses. Operational advantages include increased system capacity and enhanced safety and comfort for the operator. The data obtained up to now indicate that the system can operate reliably in mine production

May 1, 2002

By V. K. Alves, P. Lacoste-Bouchet

"In order to improve ball milling efficiency in pellet plants, Companhia Vale de Rio Doce (CVRD), experiments new technologies in Santa Luzia (M.G. – Brazil) research center facility. Pilot grinding tests have been conducted with small grinding media, size distributed from 5 to 12 mm (millpebs). Tests have been conducted on an ore from CVRD’s Usina 5 Nibrasco, in Vitória, Brazil. A sample of the regrind circuit feed was obtained and used in comparative grinding tests with two types of grinding charges: 100% balls and a blend of 70% balls and 30% millpebs by weight. According to the balls charge, the grinding media mixture has showed the following benefits: reduction of the power draw, increase of the mill capacity, reduction of the circulating load and a slight increase of the ore blaine. Following the results obtained, CVRD is going to further explore the regrinding potential of millpebs.INTRODUCTIONCompanhnia Vale de Rio Doce (CVRD) is the largest mining company in Brazil. CVRD is involved in iron, base metals, gold and bauxite industries. Moreover, CVRD operates several pelletizing plants in Brazil and in other countries.CVRD’s Center for Mineral Development (CDM) is equipped with a comminution laboratory where studies are carried out that are aimed at the optimization of existing plants at several mining sites as well as the technical and economical feasibility of new projects. The laboratory is equipped with a complete pilot plant with several mills and classifiers, enabling continuous grinding tests in grinding circuits of almost any capacity and characteristics.In January 2004, CVRD undertook to conduct pilot tests at CDM for evaluating the effect of small grinding media on ball milling efficiency. Generally speaking, it is not unusual for operators to add oversize grinding media in a conventional regrind mill. This fact originates mainly from prohibitive prices of grinding media below 25 mm due to a production capacity decrease of grinding media producers. The size of the grinding media is an important variable affecting ball milling efficiency. Use of oversize balls decreases the number of contact surface between which particles can be caught and broken."

Jan 1, 2005

The 1969 Lignite Symposium was held at Grand Forks, N. Dak., on May 1-2, 1969. Cosponsored by the University of North Dakota and the Department of the Interior, Bureau of Mines, the meeting was the fifth in this series. Registrants from many States and Canadian Provinces attended the meeting representing many segments of energy-oriented companies, State and Federal Government, and universities. At 2-year intervals, these symposia provide a common meeting place where recent research and developments in technology and utilization of energy resources with emphasis on solid fuels (lignite) are presented. Proceedings3 of the previous symposia including a Forum held in 1958 have been published.4

Jan 1, 1970

By Carlos Magno Palacios Arbizu

La calidad total es la estrategia que busca la mejorar la productividad y eficiencia de los productos que ofrece -en tanto sean reconocidos por este valor-, de forma que genera competitividad en las organizaciones peruanas y se presenta como respuesta a nuevos enfoques de gestión surgidos ante el proceso de globalización. En este sentido, el presente trabajo analiza la forma del avance en el nuevo enfoque de gestión de las empresas mineras, para así proponer alternativas de tratamiento e implementación de un modelo basado en la Calidad Total, de manera que esté alineado dentro de un sector que tenga características propias y diferenciadas de organizaciones de otros sectores productivos.

Sep 12, 2005

By Laura Bustemante, Bruce Vandenberg, Fred Huettig

Recent advances in solid-state, field portable, fast framing video camera systems and PC based frame capture hardware now allow blast imaging up to 1000 frames per second. Up to 8 seconds of data can be stored directly into the unit, downloaded to a PC or archived to a standard VCR without data compression. Since no film processing is involved, motion analysis can be performed instantly and on-site within a few minutes. This paper will describe the design features and applications of the KineView 1256P system and compare these with the analogous aspects of fii based cameras.

Jan 1, 1998

By Luis Alberto Martinez Tipe

The paper show how the inclusion of the uncertainty of the geology of the orebody into the mine planning and design process can be of great help, for the mine planner, in both assessing and quantifying the existing risk in the key project indicators such as DCF, and ore tonnage. This is achieved by using conditional simulation and Monte Carlo techniques which provide equally probable models of the original orebody model of the deposit. In this fashion, it is possible to assess the sensitivity of the pit design and related long-term production scheduling (cutbacks) to grade uncertainty.

Sep 12, 2005

By D. Randolph Berry

The objective of this program was to develop a system to extinguish coal mine fires by remote sealing of the underground passageways. The system developed had to be versatile enough to function under a wide range of operating conditions, including large variations in passageway geometry, depth of mine, water conditions, both in the mine and at the surface, and rubble in the mine passage. The system developed had to include instrumentation for the remote probing of the passageway prior to sealing, a system for sealing the mine passages, and instrumentation for remote monitoring of the quality of the seal during and after construction. These objectives were successfully achieved during this program. The remote mine sealing capability of the system was satisfactorily demonstrated in a field test conducted at the Eastern Associated Coal Corporation Federal No, 1 Mine in Grant Town, West Virginia.

Jan 1, 1973

By D. W. Partridge, W. Lamb, A. E. Lamb, S. Bird

Due to the constant need to improve SAG mill performance and efficiency, extensive research into all aspects of SAG mill optimization has been performed. This paper will review the current evolution of SAG mill shell liner design and their performance at the Copperton Concentrator. The effect of these liner design changes will be discussed with respect to: • Liner configurations • Mill operating performance, i.e., throughput, power draw, mill control • Mill mechanical performance, i.e., liner wear profiles, liner life, liner breakage, liner hardness • Foundry manufacturing considerations • Economic evaluation of throughput versus liner life This paper will discuss the results of Kennecott Utah Copper’s (KUC) and ME International’s (MEI) test work, providing an insight into the past, present and potential future opportunities of SAG mill liner design.

Jan 1, 2002

By F. Petkovich, M. P. Sudbury

Development of a new method of treating flotation concentrates for the preparation of feed suitable for direct charging to blast furnaces or converters is described. The method takes advantage of the fact that pyrrhotite contained in the concentrates can be made to undergo exothermic reactions which, under properly controlled conditions, result information of oxidation products that serve to cement the concentrate particles together. Thus green concentrates either in the form of pellets or briquettes containing 5 to 8 pct moisture not only were hardened, but also completely dried autogenously by continuous countercu,vrent shaft treatment with air. The process was developed through pilot plant operations ranging from 35 1b per hr to 2.5 tph, culminating in products evaluation tests on a railway-car scale. Falconbridge Nickel Mines Ltd., Falconbridge, Ont., have practised sintering, on a travelling grate machine, for many years to prepare a pyr-rhotite-bearing Cu-Ni sulfide flotation concentrate for blast furnace smelting. In recent years the development of new mines, and the construction of concentration plants some 40 miles from the smelter has increased the quantity of concentrate shipped, and encouraged the search for a method of producing dry, hard pellets or briquettes suitable for direct charging to a blast furnace or converter, and capable of withstanding considerable handling. The cementing properties of pyrrhotite oxidation products were discovered during a search for a suitable agglomeration method for sulfide concentrates, and were exploited in a process subsequently developed for autogenously drying and hardening pellets and briquettes of pyrrhotite-bearing Cu-Ni sulfide flotation concentrate. EARLY TEST WORK The production of hard, dry pellets of concentrate filter cake was attempted in the drying plant of one of the new concentrators. While soft pellets were produced containing 5 pct moisture, attempts at further drying resulted in disintegration of the pellets and intolerable dusting. The plant therefore was controlled to produce a concentrate containing about 6 pct moisture. The partially dried concentrate, which was shipped to Falconbridge for sintering, tended to heat spontaneously in transit. An at- tempt to briquette the moist concentrate at Falconbridge, in a plant incorporating a muller, a 20-in. roll briquetting press, and a steam-heated travelling grate oven, was more successful, although the equipment corroded rapidly due to the acid nature of the concentrate after spontaneous heating had occurred. LABORATORY STUDIES OF SPONTANEOUS HEATING OF CONCENTRATE The spontaneous heating of partially dried concentrate was studied in the laboratory. Moist concen-

Jan 1, 1961

By Stephanie Price

Engineering Associations ?Regulatory authority ?License individuals and firms ?Discipline licensed members ?Enforce against improper acts ?Programs for EIT?s, competence, etc

Oct 1, 2010

By M. W. Von Bernewitz, W. J. Sharwood

So far as is known , there is no complete bibliography on sampling, therefore , this one should be of value . In it are nearly eleven hundred references , some dating back 30 years , on sampling at mines , mills , smelters , power plants , pumping stations and refineries . For convenience , there are included a few references to methods for sampling such materials as leather belting in mills , salt impregnated soils , and mine waters . All the important technical journals , - including some in foreign countries- and engineering society publications , also mining and metallurgical text - books , have been studied for anything concerning sampling , and while it is not claimed that every important reference has been listed , the bibliography is fairly complete . The arrangement is alphabetical by authors ' names , and the references are numbered serially in the crder that they appear in the bibliography . Anonyous references are listed under the name of the journal in which they appear , and are numbered like the references bearing an author's name . Patents are grouped in their numerical order , without index nu.bers . Under the heading , " U.S. Bureau of Mines Publications " , are listed all publications of the bureau that deal with sampling . While the serial number is omitted , these same references , of course , have serial numbers where they appear in the list arranged alphabetically by authors .

Mar 1, 1922

By Paul J. O'brien, George N. Neary

"The base metal mine at Buchans, Newfoundland, has been producing since 1928. For many years, mill tailings were disposed of by dumping into a nearby natural watercourse via which they were transported to Red Indian Lake and deposited. In 1965, environmental concerns prompted the establishment of settling ponds near the mine site. Effluents fed to these ponds included slimes washed from mine backfill sand and waste water pumped from underground as well as mill tailings. Dusting around the perimeter of the ponds was first observed around 1970and within a couple ofyears reached serious proportions. A program to alleviate the condition by developing a vegetative cover over the tailings was commenced in 1974. The work was successfully carried out and demonstrated that the large area of waste could sustain a permanent cover of grasses.This paper outlines the experimental work done at Buchans as well as the procedures followed and the problems encountered in carrying out full-scale revegetation."

Jan 1, 1981

By Sanjeev Malhotra

The American Petroleum Institute (API) method of predicting pile capacities in sands is reviewed. Factors that influence pile capacity such as soil parameters, pile parameters, loading effects and installation effects are listed. In addition, the simultaneous occurrence of physical phenomena such as grain crushing, pile shaking, stress-redistribution and plugging add to the uncertainty in the prediction model. To better understand the method of prediction, each parameter and the associated uncertainty is revisited. It is evident that these factors are inter­related and sometimes compensating. This discussion also draws attention to the influence that pile installation procedures can have on pile capacities and highlights the need for field experience with various pile installation procedures for designers. In summary, the strength of the method lies in its simplicity and ease of application, but the possible savings generated by an improved method are too substantial to ignore.

Jan 1, 2000

By J. W. Davis

In the last few years major industrial companies have begun to realize the importance of Reliability as an enterprise strategy that, properly implemented, will improve financial performance. Typical results of an effective Enterprise Reliability Strategy include a 20% -50% reduction in maintenance cost accompanied by a 5% - 10%increase in real production capacity, with no capital investment in production equipment. One factor fueling the race to acquire and implement enterprise reliability is the pressure for companies to be increasingly cost-effective and competitive in global markets. In a recent study, Asset Productivity: The Next Wave, the Boston Consulting Group (BCG)stated that, “In order to compete for funds, companies must offer investor returns that are competitive with other opportunities. Alternative investments such as dot-com and others with non-traditional business models have raised the bar.” (APDF version of the study can be downloaded at www.bcg.com). BCG views asset productivity as the most powerful mechanism for increasing shareholder return. The author believes that the most effective way to increase Fixed Asset Productivity is to maximize asset utilization by increasing the Reliability of the Assets and the associated processes. Developing and implementing an ERS requires significant effort and knowledge. Most companies have difficulty finding a sufficient supply of these valuable commodities to implement an ERS Program internally. Many companies also struggle with figuring out how to get started and what direction to proceed.

Jan 1, 2003

By H. K. Taylor

Ore reserves are inadequately defined. Geological reconnaissance and pre-feasibility mining work generate a broad range of valid tonnage estimates, many published for the benefit of various interests, who may view all figures as reserves. This work reviews the regular estimation of tonnages, grades and relevant factors for single deposits. A consistent framework of definition is suggested which, by conforming to the known structures of feasibility studies and long-range plans, avoids the pitfalls of over-categorisation and of unrealistic promises. Applications are based on North American experience but are intended for general use

Sep 1, 1991

By N Stoitis, L Lien, B Tapley

The treatment of hypersaline waters originating from numerous gold projects within the Western Australian Goldfields region via membrane technology has been assessed. A combination of Ultra-filtration (UF) and Nano-filtration (NF) using Ecotechnol’s modified elements effectively removes the polyvalent ions responsible for the high lime and cyanide consumption as well as the prevalence of scale formation characteristic of gold operations in this region. Through removing up to 98% magnesium, 94% calcium and 99.7% sulfates from hypersaline water with total dissolved solids from 40,000mg/L to 250,000mg/L, Ecotechnol and subsequent independent tests have demonstrated up to an 87% reduction in lime consumption and through the ability to increase the operating leach pH, reduce cyanide consumption by up to 28%.CITATION:Tapley, B, Stoitis, N and Lien, L, 2015. Modified nano-filtration membrane treatment of hyper-saline goldfields water – an overview and benefits to gold plant operation and economics, in Proceedings MetPlant 2015, pp 431–463 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

Crushing Plant Process Optimisation Design of processes in order to find the most efficient solution to a specific task is a difficult problem. Often the number of solutions are large and the optimal solution is therefore difficult to identify. Crushing plant process design is no exception from this statement. In order to find the best solution issues like equipment selection and process configuration must be mastered. The solution must both be technically feasible and preferably have a low operating cost. Since crushing plant design is a complex task with a large solution space it is basically impossible to master without a specialised tool. For a long time simulation softwares have been used to assist in the design process. These tools only give answers for how a user defined plant will operate. There are no tools with capabilities to consider different design options in order to determine what the most efficient solution looks like. In this paper a method for crushing plant design optimisation is presented. The novel method utilises a combined optimisation routine and expert system in order to find the most cost efficient solution to a given process task. The user will only need to define the feed material properties, the process capacity, and the end product requirements. The developed system will find the solution lowest production cost per ton.

Sep 13, 2010

By Orr C. W

Continuing the systematic investigation of the influence of elements on the properties of lead(1). If the effects of additions of copper (up to 0.3%) on Port Pirie lead have now been determined in so far as creep rate is concerned.The results in the present paper contain also a survey of the influence of copper on the micro-structure of lead, a feature which has not appeared in the previous papers of this series. Further, it has now become known that creep is but little related to the more usually determined properties such as hardness and tensile strength. Since, however, these properties are of considerable importance in connection with the fabrication and use of this metal. Brinell hardness determinations have also been made and are here included.It is becoming more and more realised also that to be useful, creep data should refer to stresses of the order of those used in practice. This is due to the fact that as soon as deformation takes place, the properties of the metal are automatically changed. Lead does, of course, creep during industrial use, and probably (in lead chamber construction for example) extensions of the order of 5%...

Jan 1, 1938

By Leandro de Arruda Santos

O objetivo deste trabalho foi avaliar o comportamento mecânico sob flexão de um instrumento endodôntico constituído de Ni-Ti M-Wire e comparar suas respostas com aquelas obtidas de um instrumento de Ni-Ti superelástico convencional com a mesma geometria, utilizando-se simulação por elementos finitos. Um instrumento ProTaper Universal F1 foi selecionado para este estudo. O modelo geométrico para a simulação numérica foi gerado através de micro-tomografia computadorizada e os dados para os modelos constitutivos foram obtidos por meio de ensaios de tração realizados em laboratório. A simulação numérica foi realizada em ABAQUS, com condições de contorno baseadas na especificação ISO 3630-1. Os resultados mostram que instrumentos de Ni-Ti M-Wire apresentam maior flexibilidade e menores valores de tensão quando submetidos à flexão, o que indica que estes instrumentos são mais resistentes à fadiga por flexão.

Aug 8, 2018

By A. B. Hooker, L. C. IlsLey

"Observation of the use of trailing cables in ""mines shows that the chief limiting factor in the life of the cables and their safe use is the smashing or crushing of the cables in service, together with the effects of consequent splicing.Trailing cables are crushed when run over by cars, mining machines; and locomotives or when hit by falls of roof. Crushing damages the insulation and may cause failure at once or in later use. Failure may be either by short circuit between the conductors or by grounding to the track. The failure of a live cable causes electric arcs capable of igniting explosive mixtures of methane and air. Every cable failure in a gassy or dusty mine is, therefore, a real or potential hazard.Some mine operators do not allow the splicing of trailing cables for use in gassy mines, bet require that a damaged cable be immediately replaced and if repaired that it be used only in nongassy mines. Other operators allow the making of temporary splices to permit completion of the shift but require that such splices be remade and vulcanized before the cable is used again.Still other operators allow the continued use of temporary splices, which in general means that a cable is used until the splices give trouble in reeling, or overheat, or pull apart. Then the spliced sections are either cut out or the whole cable is replaced.Splices often determine the useful life of a cable. A splice poorly made may pull apart ueder mechanical strain and cause arcing that burn* the surrounding cable or ignites as or coal-dust. If it has lower conductivity a splice is the first part of the cable to heat; it may become so hot under load that it will burn apart and damage other parts of the cable, or, if it be a soldered splice, the solder may melt and allow parting of the cable. A poorly made splice often has insufficient insulation which may alloy short-circuiting between conductors or permit external contacts capable of giving an electric shock to one handling the cable. The splice is sometimes bulky from too much insulation and takes up too much room on the reel, causing uneven reeling; also by catching on the spooling device the oversized splice may receive expressive pulls and wear. Splicing is therefore a very important factor in the use of trailing cables."

Mar 1, 1932