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By Rick Moignard

Relationships between Information Technology providers and their clients are often segmented according to job specific tasks. As a consequence, technology providers tend to focus on automating repetition and complexity, resulting in software that improves individual productivity while failing to address the interdependency of mining functions. For this reason, technology vendors like Gemcom are following partnership approaches with their clients, engaging corporate and operational stakeholders to better understand mining business objectives. This presentation examines some of the approaches that help foster the development of solutions that leverage the information produced during mine operations to improve downstream process control and tactical decision support.

May 1, 2006

By G. Scamans, J. Lazaro-Nebreda, Z. Fan, J. B. Patel

"Melt quality is crucial for both continuous and shape casting of light alloys and in order to improve it, removal of excessive inclusions, accumulated impurities and unwanted gases becomes necessary. To address this problem, a new multi-purpose high shear liquid metal treatment technology, based on intensive melt shearing by a rotor/stator unit, has been developed. The device ensures achieving uniform temperature and chemical composition and an efficient dispersion of gas and solid phases in the melt with minimal disturbance of melt surface, and can be used, among other things, for de-gassing and de-ironing of Al-alloy melts. Efficient degassing is achieved by dispersing each argon bubble into many small ones, which significantly increases the overall surface area of the bubbles and the time they remain in the melt capturing hydrogen before reaching the surface. This allows using much lower inert gas flow and mixing times than conventional rotary degassing. When applied to Al-alloy scrap, with accumulated iron, the high shear melt treatment speeds up the nucleation and growth of primary Fe-rich intermetallic particles, allowing a faster removal rate. Therefore it reduces processing times, increasing recycling productivity, and facilitates full metal circulation of secondary Al-alloys.INTRODUCTION Aluminium and magnesium alloys are widely considered in various industrial sectors for the purpose of weight saving (Polmear, 1995). In particular, they are used in the automotive sector, where components are mostly manufactured by high pressure die casting (HPDC) because of its simplicity and relatively low cost, but efficiency and mechanical properties are quite low compared with other processes. To date, the main focus to overcome this problem has been for improving the HPDC machinery (Dahle, 2001) but little attention has been paid to the opportunities of controlling the nature and quality of the molten metal supplied to the die. In this way, liquid metal treatment, which involves a variety of physical and/or chemical processing methods to improve melt quality prior casting, is crucial for both continuous and shape casting products."

Jan 1, 2018

Accurately modeling and predicting long term mill throughput is one of the challenges facing metallurgists, geologists and mine engineers in their quest to consistently deliver accurate life of mine business plans. Batu Hijau has systematically improved long and short term mill throughput predictions since feasibility and commissioning in 1999. This has been achieved through a combination of ongoing improvement to the geology ore hardness and grade characterisation model, drill and blast optimisation and, by application of these data to model mill throughput. Batu Hijau has demonstrated the ability to consistently estimate long term mill throughput within ±2% accuracy. Aside from reliably predicting expected production rates with the existing plant configuration, this predictive ability provides a solid foundation for identifying operating and design criteria for short term grinding circuit optimisation and future expansions. This paper discusses ongoing throughput prediction model development at Batu Hijau based on geo-metallurgical characterisation. Also discussed are tools used for day to day production performance management. This includes on line "Mine to Mill" variable monitoring to improve operations parameter ecision making and performance assessment.

Nov 1, 2011

By F. Wirfiyata

"Accurately modeling and predicting long term mill throughput is one of the challenges facing metallurgists, geologists and mine engineers in their quest to consistently deliver accurate life of mine business plans.Batu Hijau has systematically improved long and short term mill throughput predictions since feasibility and commissioning in 1999. This has been achieved through a combination of ongoing improvement to the geology ore hardness and grade characterisation model, drill and blast optimisation and, by application of these data to model mill throughput.Batu Hijau has demonstrated the ability to consistently estimate long term mill throughput within ±2% accuracy. Aside from reliably predicting expected production rates with the existing plant configuration, this predictive ability provides a solid foundation for identifying operating and design criteria for short term grinding circuit optimisation and future expansions.This paper discusses ongoing throughput prediction model development at Batu Hijau based on geo-metallurgical characterisation. Also discussed are tools used for day to day production performance management. This includes on line ""Mine to Mill"" variable monitoring to improve operations parameter decision making and performance assessment."

Jan 1, 2012

By P. Cleyle, K. McDermott, M. Hall, C. A. Harris

"This paper describes the implementation of an expert system for monitoring and control of the NO. 4 autogeneous mill and spiral circuits at Wabush Mines.This process control system incorporated the mill operating expertize of Wabush Mines operating personnel and was implemented to improve spiral iron recovery and mill productivity by:1. Continuously monitoring the mill power draw and ensuring that the mill feedrate is regulated to prevent damage to the mill motor, while simultaneously maintaining the feedrate at or as close as possible to the maximum feedrate determined by the process supervisor.2. Improving control over the spiral density and feed rate.3. Improving control over both tbe rougher and cleaner wash water.4. Reducing the frequency with which pumps are plugged.5. Allowing modifications to be made easily and quickly to test various operating strategies.This system was installed using COMDALE/C, a real-time Expert System for Process Control. It was readily accepted by the process operators and produces higher production performance in comparison to the other 5 parallel mill lines at a lower power draw."

Jan 1, 1992

By D. J. Houlahan

ABSTRACT Sorting has the potential to massively improve the pro?tability of mining base metal, hard-rock ores. However, several barriers to the increased application of sorting have been identi?ed, including a lack of mineral-speci?c sensors available to the industry. This paper presents the outcomes of acollaborative project to develop an induction-balance sensor speci?cally for low-grade copper and nickelores. A review of the basic principles of induction-balance sensing and of the sensor-rock interaction is presented. Early development and testing of the sensor on ores from the Thompson nickel belt in northern Manitoba is discussed. Shortcomings of the prototype identi?ed in early testing have now been over-come, leading to improvements in design and construction, as well as sensor accuracy. The improve dsensor has now been tested on additional ores from the Sudbury Basin, with good results. A discussion of potential applications is presented and recommendations for future development are made.

Jan 1, 2010

By Paul Armstrong

THE first discovery of lead and zinc ore on Calumet island was made in 1893 by John Lawn, who then staked a portion of the property now owned by Calumet Mines, Limited. His discovery was developed by James and Calvin Russell, who are said to have shipped a few tons of sorted ore, averaging 39 per cent zinc, 13 per cent lead, and 11 oz. silver per ton. In 1898, the property was being operated by the Grand Calumet Mining Company, who mined and shipped, for treatment in a Belgian smelter, 1,100 tons of ore averaging 32 per cent zinc, 9 per cent lead, and an unreported content of gold and silver. After some indecisive exploration by an American syndicate in 1907, the property lay idle until1910, when the Calumet Metals Company-later reorganized as the Calumet Zinc and Lead Company-re-commenced exploration. After sinking an 85-foot shaft-the McDonald shaft-and doing a few hundred feet of drifting and cross-cutting, this Company, in 1912, erected a 150-ton daily capacity gravity-concentration plant, in which some 800 tons of ore, mined from the McDonald shaft and Bowie pit, were milled. Owing to very disappointing mill recoveries, the property was shut clown and-after several years of idleness-in? 1916 the mill and mining plant were destroyed by fire and the Company went into bankruptcy. In 1918, an unknown operator shipped to an Omaha, Nebraska, smelter 22 tons of ore, probably sorted from the dumps of the Ste. Anne shaft and Galena pits, averaging 44 percent lead, and 0.26 oz. gold and 61 oz. silver per ton. The British Metals Corporation (Canada), Limited, in 1926, optioned the property. They unwatered the McDonald shaft and, after doing an additional 300 feet of cross-cutting and drifting on the 85-ft. level, estimated there were some 33,000 tons of ore between this level and the surface. Surface exploration, including trenching, on other showings on the property gave discouraging results and the option was dropped.

Jan 1, 1941

By H. O. Seigel

Induced Polarization includes many types of dipolar charge distributions set up by the passage of current through consolidated or unconsolidated rocks. Among its causes are concentration polarization and electrokinetic effects in all rocks and the phenomenon of Overvoltage in rocks containing electronic conductors such as metallic sulphides and graphite. In normal rocks the polarization effects may be usually con-fined within relatively narrow limits and any large departures may be at-tributable to the presence of electronic conductors. In practice, Induced Polarization is measured in one of two ways. In the first a steady current of some seconds duration is passed and abruptly interrupted and the slowly decaying transient voltages existing in the ~round are measured after interruption. This is known as the "pulse", "transient", or Direct Cur-rent Induced Polarization (D.C.I.P.).The second method entails a comparison of apparent resistivities using sinusoidal alternating current of two or more frequencies, generally within the range of 1/10 to 10 c.p.s. Induced Polarization extends the

Jan 1, 1962

By B. Wasmund, M. Parravani, M. Jastrzebski, Z. Coull

"One of the main drivers of overall profitability of pyrometallurgical vessels is refractory lining campaign life. Increased economic pressure to improve vessel life requires innovative solutions to the problem of refractory cooling. Hatch has recently developed a high-intensity, waterless cooling system that bridges the performance gap between external shell cooling and internal water-cooled copper elements. External shell cooling has a limited effectiveness in protecting the refractory lining, because it is thermally insulated from the hotface of the lining by its thickness. This situation does not improve until the lining itself has become worn near the end of the campaign. The patented technology developed by Hatch overcomes this problem by positioning high-velocity air-cooling channels within the lining, closer to the hotface where the cooling benefits can be realized throughout the entire duration of the campaign. The current paper presents the development and application of Internal Air Cooling technology as well as results from the pilot campaign in an operating commercial vessel. Various adaptations for this novel, cost-effective and inherently safe system are also discussed."

Jan 1, 2015

By A. L. McAllister

"MASSIVE sulphide deposits are found in two areas of New Brunswick, the St. Stephen area and the Bathurst-Newcastle area. In both, the geology in the immediate vicinity of the sulphide bodies is largely inferred from drilling results as outcrop is not plentiful and is, in fact, almost lacking in most places. With few exceptions these deposits have not been explored by underground methods. Consequently much of the. detail on the geology will only become known over a period of years as economic conditions make mining feasible.Much of the information contained in this paper has been supplied directly by company geologists. As a result of the number of contributors, some confusion of nomenclature bas to be anticipated. Cross-sections and plans of the individual deposits are, in most cases, as supplied by the companies concerned. Most of the interpretations are the responsibility of the author."

Jan 1, 1960

By M. R. Hegge

The Jabiluka One and Two uranium deposits occur in Lower Proterozoic metasediments of the Cahill Formation, which is part of the Pine Creek Geosyncline in the East Alligator River area, Nothern Territory. The Jabiluka One deposit coincides with a "window" through unconformably overlying Middle Proterozoic sandstone of the Kombolgie Formation; Jabiluka Two is completely covered by that sandstone. The observed part of the Cahill Formation exhibits four horizons which are favourable hosts for uranium mineralization. These have been folded into an east-southeast-striking, gently plunging, open asymmetric syncline-anticline structure. The host rocks are mainly chlorite and/or graphite schists and their brecciated equivalents which have undergone initial regional prograde metamorphism to the amphibolite facies, then retrograde metamorphism to the greenschist facies. Mineralization consists of pitchblende, mainly filling open spaces and to a lesser extent in disseminated form. Chlorite, pyrite and quartz are commonly associated with the uranium mineralization. A portion of the Jabiluka Two deposit contains economic concentrations of gold. Structural preparation with low-pressure conditions at these sites appears to be the most significant ore control. Genetic hypotheses favour initial deposition in Lower Proterozoic sediments, followed by remobilization during later orogenic events. The deposits bear a marked similarity to some pitchblende deposits in central Canada.

Jan 1, 1977

By F. Schulz

NA's primary smelter has continually increased its production output in the past decade, making it necessary to improve the lifetime of the casting moulds for copper anodes. The current throughput of more than 1,100,000 tonnes per year of copper concentrates amounts to an output of about 450,000 tonnes per year of anode copper at NA's Hamburg plant. The anodes are cast on a single casting wheel with 24 anode moulds. Besides the stable chemical analyses, the reproducible geometry of the anodes is an important precondition for the success of the subsequent electro-refining process. The anode moulds are subjected to thermally-induced alternating stress and side reactions with the melt. Typical signs of wear will be shown and discussed. Different processes to produce anode moulds will be introduced and the results in terms of their lifetime and the quality of the anodes themselves will be discussed. Finally an outlook is given on possible efficiency improvements.

Jan 1, 2007

By Neil Campbell

"The gently-dipping Devonian dolomite beds south of Great Slave lake in northern Canada are nearly every-where concealed by a cover of glacial drift and muskeg. Nevertheless, in 1898 or earlier, four small outcropping areas of dolomite, richly mineralized with lead and zinc sulphides, were discovered. Exploration work performed here up to the end of 1930, included intensive trenching and drilling of the showings, together with mapping and wide-spaced drilling in the surrounding region. This work proved that the discoveries are isolated pockets of mineralization much too small to be commercially valuable by themselves. No evidence of orebodies elsewhere was reported.Meanwhile, mapping by the G.S.C. in the Shield far to the east disclosed major Precambrian faults, some of which can be projected southwesterly (under a cover of Paleozoic sediments) to the vicinity of Pine Point. During the period from 1940 to 1947, consideration was given, by The Consolidated Mining and Smelting Company Ltd., to evidence of a theoretical possibility that, although apparently dormant in Paleozoic times, these faults may have provided a structural control and a source of ore-bearing solutions in some post-Devonian period. From this, it was postulated that the breaks might have created, in the overlying dolomite, a linear array of orebodies concealed by overburden but lying in a belt of considerable length and in a position predictable within practical limits. A program of drilling designed to test and exploit this specific concept was conducted from 1948 to 1955.he drilling within the new, theoretically-defined search area resulted in the discovery of many lead-zinc ore-bodies, none of which was exposed at the surface. Some of these are large and (as indicated by 1965 production records) very rich. They are situated 1 to several miles distant from, and apparently not connected to, the earlier-known surface discoveries. The drilling also disclosed that the ore, which consists of disseminated sphalerite and galena replacements together with colloform sphalerite and coarse galena cavity fillings, occurs mainly at certain stratigraphic horizons within a large, coarsely-recrystallized dolomite barrier reef. Considerable fracturing and folding was found. It has been suggested that reef development was influenced by post-Precambrian tectonic movements associated with the old faults in the basement complex. The ore may have been deposited by solutions moving from distant sources to favourable structural and chemical environments in or related to the reef.In more recent exploration performed in the course of preparing for mining production, the rate of ore discovery within the same general geological context has been greatly accelerated by the use of new geophysical techniques and drilling equipment. Reserves of 21.5 million tons, averaging 4 per cent lead and 7.2 per cent zinc, were reported in 1965, and production from open pits at the rate of approximately 248,000 tons of concentrates per year is in progress"

Jan 1, 1966

By H. Marquis

This paper is concerned with an analysis of a number of failures of large-size, hypervelocity light gas gun chambers and barrels. A brief description of the light gas gun principle and of the various types of guns is first given. The failures and the investigations carried out are then described in detail, with the failures divided into two groups. The first group comprises those failures caused by certain conditions to which the guns may be submitted, and includes, for example, severe local heating of the bore surface causing hardening and cracking of the steel. These conditions were accidental and steps were taken to prevent them. The remaining failures were due to faults in the material or in the heat-treatment, manufacturing or assembling procedures. Specific problems, such as hydrogen embrittlement, and the use of high strength gun barrels above their ductile-brittle transition temperature by preheating prior to firing, are briefly considered. Some interesting observations are also presented on the use of surface markings, and angles of fracture of large fragments, as an

Jan 1, 1962

By S. Aram

Concrete reinforcing requires coordination among many roles: structural engineer, estimator, detailer, fabricator, installer and others. The methods used to define and represent concrete reinforcement elements and assemblies in building information models is crucial in determining the efficiency of sharing data among BIM platforms and the effectiveness of using the carried data in production planning, fabrication and site work activities. Starting from the information items that are required to be provided by BIM platforms, as defined in earlier work, we have developed the Industry Foundation Classes (IFC) bound Concepts and Model View Definitions (MVDs) for concrete reinforcement. Furthermore, in coordination with software developers, we propose guidelines for best practices for concrete reinforcement modeling. Implementing these guidelines by software providers will improve reinforcement modeling with regard to various aspects of reinforcement products like geometric representation, placement, and property specifications. The proposed approach is selected as a way to improve functionality of the shared data for production planning, fabrication, project management, and site activities. Guidelines for assigning information to rebar type and instance definitions as well as to rebar elements and assemblies are provided. An efficient method of sharing geometry and property sets among rebar instances of a rebar array is also defined.

Aug 1, 2013

By A. Taylor, E. Thorn Corthay, R. Storey

In response to requests from its stakeholders, the International Standards Organisation is engaged in development of an international standard for Energy Management Systems (EnMS) which will become "ISO 50001". This new standard will build on the successes of both the EN16001 EnMS standard that has been used by dozens of European companies, as well as the ANSI/MSE 2000:2008 EnMS standard that is currently being used in several pilot projects in the USA and Ontario. This paper provides an overview of the key points of the EnMS standards, and describes how they can be used to drive sustainable energy reductions in the metallurgy industry.

Jan 1, 2010

By Li. L.

Backfilling has become a popular solution in underground mines around the world. It reduces environmental impact of mining industry and improves ground stability. In most cases, backfill has a high water content so that it can be delivered by pipes from a backfill plant on ground surface to underground stopes. Upon deposition in the stope, the backfill tends to consolidate under its own weight, leading to a generation of excess pore-water pressure. To avoid excessive pressure and protect the backfill barricade installed at the base of the stope, the backfilling of the stopes is usually divided into two stages: plug pour and backfill body pour. The interruption of backfilling operation is undesirable as it slowdowns the mining productivity, and sometimes causes pipe clogging, leading to unexpected increase in manpower cost and further reduction in mining productivity. The backfilling interruption time may be reduced, even eliminated if the drainage of backfilled stopes is sufficiently improved. This paper presents an application of wick drains, a material commonly used in civil engineering, to mine backfilled stopes to help accelerating the drainage. A protocol is proposed for installing the wick drains in a mine stope to be backfilled. Numerical simulations were made, showing that the drainage of the backfill can significantly be improved by the introduction of wick drains. The application of wick drains in mine backfill can thus be considered as a promising technique and merits deeper and more detailed investigation.

Aug 1, 2013

By E. Y. Dougherty

Introduction As practised during the last two years at the Vipond Consolidated gold mine, mining geology has meant the application of geology to the problem of finding, developing, and mining ore. This article reviews the results attained in Vipond mining geology as thus defined. Most effort was directed toward clarifying and interpreting the tangible physical causes of vein and ore localizations, and in the following pages these questions are dealt with in considerable detail. Discernment of the influence of rock folding and deformation on the localization of veins, and of the influence of certain structures and rocks in or near carbonaceous zones on the localization of ore-bodies, have been the main practical results of the studies. Consideration of some of the geological features of the Porcupine area, and of the geology and mining experience of the principal producing mines, has helped toward a perspective of Vipond's ore-finding problems. These features are first discussed. The background and procedure for Vipond mining geology, and the major results of the geological mapping, are then summarized. Then follows a résumé of tangible factors that influenced vein, ore-body, and gold localizations; and, next, explanations of the facts ascertained. Because they were found of little utility, many fascinating problems, such as the origin and mode of emplacement of the veins and lodes(l), the ultimate source of the ore, and the physico-chemical and mechanical agencies affecting vein and ore formation, are treated cursorily or are neglected in these notes.

Jan 1, 1934

By C. R. Whittemore

PROGRESSIVE industrial organizations have recognized the importance of maintaining an adequate reference library of volumes covering all phases of their particular branch of industry, but it has been the experience of the writer that few engineers know how to use to the best advantage this store of extremely -valuable information which has been accumulated for their service. Nor does the average engineer appreciate the fact that it is only through the current technical literature that he can keep abreast of the rapidly developing fields of engineering. The present-day ramifications of the engineering field are of such wide scope that the human mind is not capable of storing away more than a small fraction of the information available on any particular topie; yet, from time ? to time, such information would prove invaluable. An engineer can know intimately only a small part of his own branch of engineering; but he cannot afford to neglect to take the fullest possible advantage of all that is already known in his own particular field. Technical information may be obtained by one or more of the following methods: (1) by enquiring of the individual who knows; (2) by performing the experimental investigations necessary to ascertain the facts; (3) by consulting the technical literature, where a record may be found of the work of others. This last method is the one we wish to examine. Our main consideration is the question of how to use the library, but first it is necessary to give some attention to the kind of enquiries one takes to the library, and to the nature of the sources of information available.

Jan 1, 1938

By Bern Klein, A. Tugba Cebeci, Libin Tong

"Sensor based sorting faces two main challenges related to limited capacity/throughput and the ability of sensors to accurately discriminate based on estimated grades. This paper is aimed at improving sensor discrimination. Sensors have the ability to measure more than a single response. X-ray fluorescence (XRF) can detect and provide concentration information about a range of elements. Similarly, electromagnetic sensors (EMs) can generate magnetic susceptibility and conductivity responses over a range of frequency levels. The sensors thereby provide a response signature rather than a simply a single response that is a proxy for a metal grade. Furthermore, integrating sensor responses can improve the discrimination of metal bearing rock from waste. A study was conducted on a gold ore to assess sortability using XRF and EM sensors. A multi-variable regression approach was used to develop models that included a range of responses. Correlations improved significantly when compared to single response correlations. The approach showed that both positive and negative correlations contributed to the improved correlations. Stepwise regression simplified the models and showed that 2nd order interaction effects can be important. The approach also showed that combining different responses can improve discrimination accuracy. An important outcome of the study was that an ore that had been consider not to be sortable was determined to be sortable through the application of an approach that used the sensor responses in a more intelligent manner.INTRODUCTIONMining is aimed at recovering valuable minerals from their host rocks. Many methods are used to recover valuable minerals, and finding efficient and cost-effective ways is the key in research and production. . Ore sorting technology is fitting this definition. It not only discards waste rocks away from the concentrator but also recovers metal bearing ore particles that could be lost to the waste dump. The benefits of ore sorting include increased energy efficiency and reduced water and reagent usage in the downstream operations (Bamber, 2008; Gunson, Klein, Veiga, & Dunbar, 2012; Mazhary & Klein, 2015; Robben, Wotruba, Robben, von Ketelhodt, & Kowalzcyk, 2013)."

Jan 1, 2016