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By Eder Salazar

El presente texto describe la optimización de la productividad en la empresa minera a través de la mejora contínua en la cadena de valor en SMEBSAA, los siete pasos de la calidad, proceso de mina, planta, soporte y la cuantiificación de dicha mejora en la cadena de valor en SMEBSAA. Asimismo, la implementación de los diversos sistemas de gestión refuerzan los resultados, siendo el Sistema de costeo basado en actividades el gran agrupador de toda la información de los módulos: Logístico, Control Patrimonial, Orden de Servicio, Planillas y Contabilidad.

Sep 12, 2005

By Eric Bain Wasmund, Lance Christodoulou, Julio Jairo Carmona Franco, María Fernanda Castillo, Jose Concha

"A number of technologies are in practice for selectively removing coarse gold from conventional grinding circuits. These circuits are often designed so that the grinding mill output is size classified, with large (or high density) particles being removed before the tails are returned to the mill. Because of the high relative SG of gold, and the fact that some forms of gold such as free gold do not break apart during conventional grinding, coarse gold can accumulate in the circulating load, and eventually be lost.Eriez has developed a flotation cell that uses fluidized water to enhance flotation of coarse particles. More than 40 units have been sold in industrial minerals, and we are now exploring applications for the HydroFloat® in the gold industry.Mineros S.A currently produces approximately 120,000 oz of gold per year by gravity concentrating alluvial gold ore with a mean particle size of 330 microns, followed by further concentration using a Falcon separator. A 400 mm diameter pilot-scale HydroFloat® was added to the tails of the Falcon to test whether additional gold could be captured. Enrichments of 50-600 times and recoveries normally in excess of 95% were achieved. This allowed direct smelting of the gold concentrate. Metallurgical results and operating parameters such as water addition and power will be discussed during the presentation.This result opens the possibility that the HydroFloat® could be used directly in the grinding circuit, for removing coarse gold in the circulating load. This work also shows the possibility that the HydroFloat® can produce a throwaway tail, which will reduce the size of the circulating load stream and the grinding requirements of the circuit."

Jan 1, 2015

By Jason M. Ryan, T Michael LeBlanc, John H. Heiiig

Drill trajectory deviation is a recurring problem in the Mining Industry retreat stoping operations. As a result of this deviation, it is quite concevable that 60 kg (165 mm 0) and 103 kg (203 mm 0) explosive charges are detonated beyond the hanging wall contact. Consequently, there follows a reduction in hanging wall stability and an increase in ore dilution.

Jan 1, 1995

By Paul Semple

"In 2007, Noront Resources Inc. discovered the high grade nickel copper PGE deposit in northwestern Ontario in a region now known as the Ring of Fire. Since the initial discovery, Noront has advanced the Eagle¹s Nest Project and in September 2012 released a feasibility study for the development of the Eagle¹s Nest Project. This paper summarizes the results of this recent study and outlines additional work planned in the next stages of project development. INTRODUCTIONThe following paper summarizes the findings of the recently completed feasibility study on Noront Resources Ltd.’s Eagle’s Nest Project. The feasibility study was compiled into a NI 43-101 report by Micon International. This paper is intended to summarize the major technical findings and for complete information, interested parties can find the entire NI 43-101 report at www.norontresources.com or on SEDAR.LOCATIONThe McFaulds Lake project area, which includes the Eagle’s Nest deposit, is located at approximately UTM 5844000 N and 547000 E, and between approximately 52º42’ and 52º50’ N latitude and 86º06’ and 86º24’ W longitude, approximately 250 km west of the community of Attawapiskat on James Bay and 575 km northwest of Timmins. The closest all-season accessible community to the McFaulds Lake project area is Nakina, 300 km to the south, where there is a paved airstrip, in addition to all weather road and railroad access (see Figure 1).The First Nations communities of Webequie and Ogoki/Marten Falls are located 90 km west and 120 km south southeast of McFaulds Lake, respectively. Both communities are served by regularly scheduled air service, primarily from Thunder Bay; both Thunder Bay and Timmins serve as support centres for the James Bay communities and the exploration projects in the area."

Jan 1, 2013

By C. E. Wood

Because of the renewed importance of the strategic metal manganese the Bureau of Mines in conducting further research on pyrometallurgical methods of beneficiating manganiferous iron ores and low-grade manganese ores. Published data on the Pyrometallurgical of manganese ores have been reviewed by Joseph.5/ A method of treatment that has received less consideration than others is the matte smelting of manganese or the separation of manganese from the iron and the gangue in an ore b, formation of a matte, that consists principally of esulfide of manganese. A procedure of this type has been patented by Betts.6/ Lofquist7/ claims advantages for the production of a sulfide-oxide matte as a method of recovering manganese in alloys containing manganese and iron.

Jan 1, 1940

By Jesse A. Pfeiffer

CPAR, the Construction Productivity Advancement Research Program, is a new initiative of the Corps of Engineers to enhance U.S. construction industry productivity through the development and application of joint-funded research. CPAR seeks to balance the requirements of both the private sector and the Corps of Engineers construction program, to identify research needs that are common to both parties in a partnership for conducting research, and to achieve practical real-world products which will enhance productivity in the construction industry. Increasing costs of doing business has had a major negative impact on much of the nation's industrial base, and research and development (R&D) is among the areas hardest hit. The Congressional Budget Office estimates that since 1984 inflation adjusted R&D outlays in private U.S. firms have risen at an average annual rate of three percent, or about half the rate of gain of the preceding decade. And, despite a significant increase in foreign competition, the portion of gross national product (GNP) devoted to R&D is lower today than 20 years ago. For the case of the U.S. construction industry, the numbers are even more dramatic.

Jan 1, 1989

By J. Alexis, G. Ye, E. Burström

Over the past twenty years the 3 MW DC arc furnace at MEFOS has been frequently used for development of new processes. These processes include recovery of valuable metals from slag, sludge and dust from steel and other metallurgical industry, treatment of ashes from power plant and incinerators, smelting reduction of minerals and zinc recovery from EAF dust. The process characteristics of the DC arc furnace operation in terms of: ? selective reduction, ? total reduction, ? process stability and flexibility, ? dust carry-over, ? thermodynamic conditions provided in the hot spot area, ? precision in composing slag products These are analysed and described in this paper based on technical results from selected test campaigns over the years and thermodynamic considerations. The electromagnetic properties of DC arcs beneath the electrode have been studied by CFD simulation. The calculated result enables us to understand some interesting technical phenomena observed. The heat balance has also been considered based on data obtained from test campaigns and heat balance calculation.

Jan 1, 2004

By Branagan D. F

The geology of the area studied is briefly described, together with the prospecting methods used in the search for copper, lead, zinc and uranium ore bodies.Four prospects, Mt. Corella, Yanasinga, Lawlor's and Greenmount, which were diamond-drilled, are described in detail and geochemical results are discussed in relation to the mineralization found. Copper anomalies were found wherever intrusive rocks were mapped, and showed a much closer relation to geology and mineralization than did the predominantly lead and zinc anomalies.Geochemical prospecting aids in the overall mineral search programme because of its speed and economy, as it helps to pinpoint areas worthy of detailed geological examination. Geochemical anomalies are a guide to favourable zones but may not indicate the presence of ore.INTRODUCTIONDuring 1953-55 the National Lead Company of New York carried out a search for minerals in an area south and west of Cloncurry (Fig. 1) in rocks of Precambrian age. After reconnaissance mapping, a number of prospects were chosen for closer examination by detailed geological mapping and geochemical sampling, and from these prospects, five sites were selected for drilling.This paper records the salient features of the exploration programme and discusses the geology and geochemistry of four of the prospects-Mt. Corella, Yanasinga, Lawlor's and Greenmount. Practically all the prospects examined showed high zinc "anomalies" or "dispersion" trains. Greta, Mt. Corella and Lawlor's prospects showed some copper anomalies and, to a lesser extent, lead anomalies. In particular, Greenmount exhibited striking copper anomalies.

Jan 1, 1960

By H. Warren Newcomen

Assessments of the stability performance of open pit highwalls have traditionally been based on consideration of surface movement rates. Although generally accepted in industry, this approach presents challenges for establishing appropriate threshold values to allow for safe mining operations and does not address the issue of total strain. Surface movement monitoring data from a limited number of open pit mining operations in North and South America has been evaluated in terms of highwall strain, rock mass quality and inferred mechanism of instability. Threshold strain levels for key stages of highwall stability proposed from previous work have been reviewed and are generally endorsed based on evaluation of additional data. An empirical highwall strain criteria for the assessment of highwall stability performance is postulated based on the observed trends in highwall strain data from the case histories presented.

May 1, 2004

THE object of the air-tight stopping is either to prevent a current of fresh air from getting into the fire area, or to prevent an escape of fumes and gases from the fire area into the workings of the mine. In the former case all is "plain sailing," but in the latter case there are certain difficulties to be overcome.In the Broken Hill Proprietary mine there were two styles of stopping used during the last fire-brick and bag and the following were the chief points that determined the use of one in preference to the other:-If the required stopping were to be more or less permanent, bricks were used, also if the area to be blocked were large-bricks being so much lighter and easier to handle than bags filled with -skimps. If, however, the air contained much gas, a bag stopping was put up. Great difficulty was experienced in getting essentially surface men, such as bricklayers, to work where there was the; slightest trace of gas; miners, however, would willingly do the work, and a bag stopping could be built without skilled labour.In old drives and gangways, where there was the liability of settlement, the bag stoppings were preferable to brick. The slightest movement around the sides or foundations of the latter would cause cracks, thus rendering the brick stopping useless;whereas, in the former, there was a certain amount of elasticity.

Jan 1, 1909

By T. Gerritsen, R. C. Delgado, J. Janzen, E. R. Veloza

The paper describes the components of an Integrated Furnace Control system for covered-arc (shielded arc) smelting with results from the recently started 75 MW Cerro Matoso Line 2 Furnace. The paper starts with a review of the mechanisms of power and feed input and heat losses in the shielded-arc smelting process, and describes how the details of the control system are tailored to the process. The control modules of a covered-arc smelting furnace are described including measured results and screen captures. This paper focuses on Integrated Furnace Controls tailored to shielded-arc smelting, but similar approaches have been recently applied to other furnace processes including immersed-arc smelting.

Jan 1, 2004

By Greaves M. C

X-ray fluorescence spectroscopy used for the analysis of mill samples results in improved control of flotation concentrators.Techniques and equipment for sampling pulp streams, filtration and drying, grinding, briquetting and X-ray fluorescence analysis of samples have been developed.The current methods in use permit the analysis for lead and zinc in six pulp samples within 30 min total elapsed from the start of sampling. The X-ray method gives a precision at least equal to the former routine wet-way assay methods.The equipment is used also for pilot plant control, as a means of solving complicated analytical problems and in the rapid qualitative analysis of exploration samples.INTRODUCTIONIn milling and concentrating operations, classical methods for the assay of lead and zinc have been mainly of use for accounting purposes and for the post-mortem examination of plant operations, but have been of little value for rapid mill control. Where attempts have been made to apply these methods to control assaying, it has been necessary to modify the procedures and introduce short cuts which have tended to reduce their reliability.Even with these shortened procedures, the time taken to obtain a limited amount of information rendered them of little value for the control of milling operations where sudden, large fluctuations can occur. In recent years, a number of new and rapid analytical techniques, based on physical rather than chemical principles, have been introduced.These include direct reading emission spectroscopy, x-ray fluorescence spectroscopy and atomic absorptionspectroscopy.

Jan 1, 1964

llmenite from the west coast of the South Island, New Zealand, shows exceptional reactivity with dilute sulphuric acid. Based on this, a cyclic acid leaching process was developed for the production of material with more than 98% TiO2, suitable as a substitute for mineral rutile.Titanium hydrate is recovered from the leach liquor by hydrolysis, and is calcined to give the required product.Ferrous sulphate is crystallized from the hydrolysis filtrates, which after concentration are returned to the leaching stage. The need for further evaluation of the process on a larger scale is indicated.

Jan 1, 1973

IF a straight line should be drawn on the map (See 1, page 96) through the northern half of the South Island of New Zealand, from Mt. Domett in the north to Arthur's Pass in the south, and another line drawn parallel to it and at a distance of ten miles to the west, according to the topographic scale, it will be found that within the belt thus drawn across the country all the most important mines, past and present, of the South Island are situated, with the exception of a few in Otago.The most important product of this tract being gold, and Reefton, the most important southern mining field, being situated at about its central portion, the zone may aptly be termed "The Great Reefton Gold Belt." The occurrence of so many gold mines along this particular strip of country is not at all a matter of chance, but is the outcome of cause and effect. Running along the eastern side of the gold belt are the Brunner and Victoria Ranges, which are chiefly composed of crystalline schists and metamorphic granite of probably Cambrian or Silurian age; between these and the gold-bearing series there are interposed at one or two places some beds of slates, limestones, and...

Jan 1, 1910

By Phillip E. Deering, Robert M. Cox

A model pillar study was conducted in which the engineering principles of dimensional analysis were applied to the problem of coal mine pillar design. The paper reviews the theory of similitude as applied to the model pillar study conducted in the investigation. An example solution of a design problem is included to indicate how the results of the study may be used as a first approximation in the design of coal mine pillars. The design of mine pillars for adequate support with minimum loss of valuable raw materials has always presented a problem to the mining engineer. Most often, for lack of a better method, past practice has influenced the design of new mine pillars. This process has always left doubt as to the safety factor of the pillars. The work presented in this paper is an initial attempt toward adapting the engineering principles of dimensional analysis to the problem of pillar design in underground mines. The use of the dimensional analysis technique is advantageous because all the variables associated with the problem are considered, and by systematic analysis the relative influence of each variable is determined. The model material utilized in this study was taken from the Helena seam of the Cahaba coal field located in central Alabama. The research study was sponsored by The Southern Electric Generating Co. as part of an over-all rock mechanics investigation of the Helena seam area. THEORY OF SIMILITUDE Model analysis is used extensively in engineering today, particularly in the solution of design problems that defy the classical methods of analysis. Such problems arise when materials with a nonlinear stress-strain relationship are involved, when geo- metric boundaries are difficult to define in simple form, when strains become large, or when partial failure occurs. All of these difficulties usually exist in pillar design problems. Those principles which underlie proper design and construction of models, and the interpretation of test results, comprise the theory of similitude. That is, the theory of similitude includes a consideration of the conditions under which the behavior of two separate entities or systems will be similar, and the techniques of accurately predicting behavior of one from observation of the other. The theory of similitude may be developed by dimensional analysis. Dimensional analysis, as a powerful analytical tool, is developed from a consideration of the dimensions in which each of the important quantities involved in a phenomenon is expressed. It is based on two axioms: 1) Absolute numerical equality of quantities may exist only when the quantities are similar qualitatively. 2) The ratio of the magnitudes of two like quantities are dependent on the units used in their measurement, provided that the same units are used for evaluating each. Dimensional analysis, developed from these two axioms, differs from other types of analysis in that it is based solely on the relationships that must exist among the pertinent variables because of their dimensions, rather than on the relationship of natural laws. In itself, dimensional analysis ~rovides qualitative, rather than quantitative relationships, but when it is combined with experimental procedures, it may be made to supply quantitative results and accurate prediction equations. APPLICATION OF THEORY The design of an adequate mine pillar requires the determination of a design equation and the selection of a dimensional system with which to work. Since force plays an important part in the design of mine support, the FLT (force, length, time) system has been used. The factors involved in the dimensional analysis of mine pillars and their dimensions are: A = cross-sectional area L Cp = design strength FL- E, = tangent modulus of elasticity FL

Jan 1, 1969

By Lyn Jones, Mike Bratty, Rick Lawrence, David Kratochvil

"The treatment of water is required at many mining operations to remove metals and prevent the discharge of contaminated water to the environment. In other cases, water treatment is used to provide better quality water for recycle to the processing plant, or to process bleed streams in hydrometallurgical operations in order to prevent deterioration in metallurgical performance or process equipment. BioteQ Environmental Technologies Inc. has developed and commercialized the BioSulphide® Process which can provide an alternative for these treatment needs and which can also be used for profitable metal recovery, particularly in cases where conventional metal winning techniques are not economical. The BioSulphide® Process is a high rate anaerobic biotechnology for on-site production of H2S from sulphur species, although for smaller flows and metal loadings, the use of chemical sulphide reagent might be more cost effective. Both new projects and existing commercial operations, used for removal and/or recovery of copper, nickel, and zinc, and which range in sulphide generating capacity from 50 kg/day to 3.7 tonnes/day, are discussed. Particular focus is placed on the results of operations at the Raglan Mine in Northern Quebec where dissolved nickel is removed from contaminated water at a high efficiency through the precipitation of nickel sulphide. Plant effluent is discharged directly to the receiving environment and the high-grade nickel sulphide product is combined with the nickel flotation concentrate produced at the mine. The plant at Raglan will replace the existing conventional water treatment plant and will eliminate the need for on-site storage of treatment plant sludge.INTRODUCTIONThe BioSulphide® Process, which produces low cost H2S for use in selective metal precipitation, offers a low capital cost alternative which can operate efficiently and cost-effectively within a wide range of flows and solution grades. Since the technology can be used to recover metals from solutions with low flows and metal grades, the technology is also applicable to environmental applications for water treatment, with the sale of recovered metals providing an offset to treatment costs. For environmental control, the technology has a distinct advantage in being able to meet strict effluent discharge criteria due to the very low solubility of metal sulphides. To date, BioteQ Environmental Technologies has designed and constructed three plants for metal sulphide precipitation, with another three projects in the advanced development stage."

Jan 1, 2006

By Adam Gray, Emery Gray

State-of-the-art seismographs can be employed to assist the blasting engineer in understanding the propagation of vibration waves generated by blasting. Wave traces and frequency plots are used to adjust shot loading and timing, especially around close or near- field structures. Successful close-in blasting vibration monitoring requires careful consideration of the following: Geophone locations Mounting of geophone both on structures and in the ground Differences between ground motion and structural response This presentation will discuss methods used to control and monitor blast-induced ground and structure motions. Case histories are presented to illustrate seismic monitoring used as a tool to control vibrations and guide the blaster in the design process.

Jan 1, 2005

By Mika Muinonen

"Dewatering of nickel concentrate at the INCO Thompson integrated mine-metallurgical site takes place within the smelter plant. The eight original 60 foot diameter cable torque thickeners of which four were operational and eight Dorrco internal drum filters have been replaced with a single Outokumpu high rate thickener and a single Lasta pressure filter. The modernization has resulted in a filter cake which has a more stable and lower moisture content. Control of the entire dewatering process has been improved and costs have been reduced.Typical filter cake produced from the Dorrco filters during processing of high tonnages of Birchtree mine ore was ~20% moisture vs. ~13% moisture for concentrate produced from the Thompson mine ore. The high moistures were correlated with the amount of fine magnesium silicate gangue in the concentrate. As Birchtree ore processing rates have increased, this filter cake moisture became unacceptable because of material handling problems and the impact on furnace metallurgy. The Dorrco filters were replaced with the Lasta filter in 2003 that has consistently produced filter cake at ~11% moisture.This paper summarizes the piloting, design, installation and commissioning of the modernized dewatering circuit.INTRODUCTIONThe Thompson integrated nickel processing facility was built in 1958 and originally consisted of a mine-mill-smelter and, soon after, a refinery.Nickel concentrate is pumped from the mill as a dilute slurry directly to the smelter facility ~200 meters along an unheated pipe trestle. Originally, nickel concentrate was de-watered using up to 8 conventional 60-foot diameter thickeners and 8 internal vacuum drum filters."

Jan 1, 2006

By A. A. Stripling

The Cretaceous limestone wells of the Mara/Maru-caibo Dist. of Venezuela are extremely prolific producers. To maintain production on cessation of natural flow, large scale gas-lift operations were commenced involving high production rates on caring Flow. For the design of these gas-lift installations it was essential to have some knowledge of the pressure gradients involved in casing flow, so that the required injection pressures, optimum gas injection raws, etc., could be forecast. This paper presents a method of calculating these annular pressure gradients. Basically the method makes use of an energy balance equation coupled with an empirical energy loss factor derived from field data. The calculations have been put in a form suitable for "punch card-type" calculating machines. A set of gradient curves for Mara/Maracaibo conditions covering flow rates up to 12,000 B/D, and GOR's of 500 to 2,000 cu fd/bbl is presented. From these curves the flowing BHP can be predicted from surface data and the vertical pow performance under varying conditions of gas injection can be estimated. The method has been applied to La Paz and Mam gas-lift operations for over three years and has given consistently accurate results. INTRODUCTION The Cretaceous limestone fields of the Mara/Maracaibo area in Venezuela are characterized by the presence of widely distributed fissure systems. Under these conditions individual wells frequently have extremely high potentials and such wells are generally flowed on the casing-tubing annulus in order to reduce the pressure loss in vertical flow. To maintain production on cessation of natural flow, an extensive gas-lift system was planned. As a first approach to this gas-lift design problem, an attempt was made to construct a set of empirical flowing gradient curves from the available subsurface pressure data. Such a method has been used successfully for tubing-flow conditions in California by Gilbert'. Unfortunately, the empirical construction of casing-flow gradient curves presents additional difficulties, as pres- sure bombs cannot bc run in the casing-tubing annulus against high rates of flow. Thus, the Full flowing gradients cannot be defined by actual measurement and the best that can be done is to obtain spot pressures at the tubing shoe. Under these conditions a vast accumulation of BHP data is required to construct a set of gradients. To the La Paz and Mara fields the majority of the available flowing pressure measurements fall into a relatively narrow GOR range, in the neighborhood of the solution ratio. While there appeared to be reasonable prospects of constructing gradient curves for this limited range, measurements at higher GOR's, which were of major interest for gas-lift operations, were relatively few and the prospects of constructing empirical curves cor~spondingly remote. As an alternative approach, the possibilities of a mathematical analysis of vertical flow conditions were investigated. May and Laird2fV n 1934 presented an excellent analysis of the vertical-flow conditions in the Anglo-Iranian Oil Co.'s fields. Their analysis was based on an energy-balance equation and calculated the losses due to kinetic energy, friction and slippage separately. By combining these losses with the total calculated available energy, the required depth-pressure traverse could be deduced. On applying the method to La Paz conditions, good results were obtained for tubing flow at high tubing-head pressures. However, for lower wellhead pressures (300 psi and under) the discrepancy between calculated and measured values increased appreciably. It was considered that this was probably due to energy losses caused by slippage or liquid hang-up in a continuous gas phase, for which it was difficult to visualize any analytical approach. In 1952 Poettmann and Carpenter4 presented a method of pressure gradient calculation which, while based on an energy-balance equation similar to that employed by May and Laird, made no attempt to evaluate the various components making up the total energy loss resulting from irreversibilities of flowing fluids. Instead, they proposed a method of analysis which assumed that all significant losses for multiphase flow could be correlated in a form similar to that of the Fanning equation for frictional losses in single-phase flow. They then derived an empirical relationship linking measurable field data with a factor which, when applied to the standard form of the Fanning equation, would enable the energy losses to be determined. The total available

By A. Pratt

Portland cement is primarily used to solidify backfill in underground mine workings and it represents a major cost in mining operations. CANMET-MMSL has invented an alternative binder technology that does not contain any amount of Portland cement and is made using waste materials, such as development rock and smelter slag. The technology has been successfully tested with many types of base metal and ferrous slag. Research conducted in collaboration with several mining operations in Canada has shown that the CANMET-MMSL binder has considerable potential as a replacement for Portland cement in mine backfill. An integral part of the overall mining operation, backfill is used for two main purposes: safety and environmental remediation. Depending on the mining method used, backfill provides a working surface, stabilizes stope and pillar walls, as well as the surrounding rock mass, and controls caving of stope backs. There are several benefits associated with the replacement of Portland cement in backfill, including reductions in (i) the footprint by placement of slag waste underground, (ii) the environmental effects and long term liability resulting from disposal and containment of slag waste on surface such as acid rock drainage, (iii) GHG as a result of reduced Portland cement usage (the production of 1 ton of Portland cement produces 1 ton of GHG), and (iv) the significant costs associated with reduced Portland cement usage.

May 1, 2010