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By A. Kowalski

This paper presents methods of implementation and the added value that can be achieved by connecting personnel tracking systems and alarm-broadcasting systems. The authors point out the functions of the two systems that enable cooperation between them. Methods for connecting the systems on the surface and underground areas of mines require some intervention in both systems, so the authors point out a possible phased approach to introducing cooperation methods. Due to the fact that tracking systems in Polish mines are at an early stage of implementation, the article aims to provide new functionality, attempts to identify the needs of future users, and describes the experience of both production companies in terms of the development of cooperation methods.

Aug 1, 2013

By S. Shokri

The increasing size and complexity of mega construction projects result in having several geographically distributed stakeholders, collaborating with each other to successfully deliver the project. Electronic Product and Process Management Systems (EPPMS) are recently emerging to facilitate the collaboration between stakeholders, reduce the surprises and issues, and improve the project productivity. These are commercially successful but evolving systems. An important component of EPPMS is the Interface Management System, which aims at formalizing and automating the communication channels between stakeholders. An interface is generally considered the link between construction elements, phases, or stakeholders. An interface Management System (IMS) involves five iterative steps: (1) Interface Identification, (2) Interface Documentation, (3) Interface Transferring, (4) Interface Communication, and (5) Interface Closing. A fundamental part of step 2 is recognizing different roles in dealing with interfaces. Each stakeholder is assigned a different role, such as responsible, accountable, consulted, and informed. In a mega project, several thousands of interfaces exist with complex relationships between stakeholders. Therefore, identifying stakeholders with higher responsible roles has been requested as useful information to the project owner in dealing with some of the project risks. After the interfaces are determined, and the responsibilities are allocated, the critical stakeholders are identified using the centrality concept in Social Network Analysis. The critical stakeholders can be determined at the highest level, considering all types of interfaces, as well as for each specific type or discipline-related interfaces. The proposed methodology is applied on a hypothetical offshore project with over 500 interfaces. In fact, this project is a simplified representation of a real scale Liquid Natural Gas project. In order to reduce the complexity of calculations and clarity of explanations, the simplified case study is used. By implementing IMS in mega projects, different parties not only formalize the communication between each other, but also gain better visibility concerning their roles and responsibilities. In addition, the owner benefits from analysing the complex relationships between stakeholders to further identify critical ones, along with other criteria like package cost, stakeholders? experiences, etc.

Aug 1, 2013

By Yanping Xiao, Ton van Sandwijk, Gus Van Weert, Larry McHugh, Thomas Zabev

"All attempts to remove significant amounts of arsenic from enargite via neutral or reductive pyro routes have required operating temperatures between 600 and 700 º C, too high to propose an equipment development program. Operating at reduced pressures, or using hydrogen or elemental sulphur as a sweeping gas did not help to lower these temperatures. Admixing iron powder gave excellent results, but still required 700 º C. By fortuity, in recent experiments to produce tennantite from an enargite mineral sample, it was observed that enargite was completely converted to bornite, chalcopyrite with minor residual tennantite within an hour at 400-450 ºC. This is believed to be due to the presence of pyrite in the mineral sample treated. All earlier decomposition work appears to have been done on predominantly enargite (i.e. low pyrite) samples, or at high operating temperatures, ignoring possible reactions at lower temperature. The decomposition of enargite into iron substituted tennantite plus some bornite under evolution of liquid elemental sulphur, followed by further decomposition of this tennantite into bornite and volatile arsenic sulphides, appears experimentally feasible at these low temperatures and mimics described ore genesis pathways at > 250 ºC in saline solutions. We suggest two pathways to describe the observed experimental results:20 Cu3AsS4 + 12 FeS2 ???5 Cu10Fe2As4S13 + 2 Cu5FeS4 + 31 S(l)31 S(l) ???31 S(g) (evaporation)5 Cu10Fe2As4S13 ???10 Cu5FeS4 + 10 AsS(g) + 5 As2S3(g)"

Jan 1, 2014

By Tom Dettweiler

Who We Are A global pioneer in discovery, development and recovery of deep-ocean assets Shipwrecks Deep-sea Minerals Company Overview Founded 1994 HQ ?Tampa, Florida USA Employees 45 Tampa + 150 Abroad Publicly Traded: NASDAQ:OMEX Requires Specific Financial Controls and Reporting

May 1, 2013

By Charles Tkaczuk

In order to remain competitive the mining industry must keep up with changes in technology. Many innovative technologies from the mining perspective are commonplace in other industries. A ?Global? review of technologies will often reveal existing technologies that can be innovatively applied in the mining industry. Industries, which are rife with proven solutions include, medicine, biotechnology, security, manufacturing, telecommunications, etc. This paper addresses the communications aspect of mining where greater productivity, lower costs and the ability to quickly react to mining related events is obtained through an increase in remote monitoring and operating control. A review of the communications systems in place globally reveals technologies that, with minimal modification, can be immediately applied to the mining environment. We discuss the concept, advantages and implementation of existing communications technology from an industry that is not usually associated with the mining industry. This technology will form the basis of a solid platform on which can be built a state-of-the-art process monitoring, control, and communication system. This lays the groundwork for providing one solution to the underground mining industry?s most difficult problem, establishing a reliable, maintainable and cost-effective underground bi-directional wired/wireless data, video and analog communications system. We need look no further than our own doorsteps to find such a solution. The cable that you see coming from the simple green or brown box on the boulevard into your home contains hundreds of television broadcast channels, FM radio channels and data channels. And if you have a set-top box, you are in control of it all. The Cable Television Broadcast Distribution System suppliers of today are at the leading edge of converging all the different methods of communications onto a common carrier, coaxial cable or fibre optic cable. There is no fundamental difference between providing a reliable communications network to a city/neighbourhood/home/personal computer than there is to a mining operation/underground level/equipment or person. The principle is the same. Only the application is different. Realizing this, we can capitalize on the efforts of other industrial sectors, to solve our communications problem. Where else can you find a solution to a problem that is mature, having been developed with the input of thousands of engineers, and having hundreds of millions of dollars spent on research and development, manufacturing, distribution, global presence and engineering support?

May 1, 2003

By R. C. Wallace

It was to be expected that the convening of the first Empire Mining Congress in June, 1924 in the city of London would turn men's thoughts very definitely to the question of exploring the mineral resources within the British Empire, the examining of her strength and her weakness in mineral material, and the consideration of steps that might advisedly be taken to strengthen her trade in minerals. That expectation was in part realized, though in the British way of presenting the case, and permitting the inferences to be drawn by implication. The opening address by the President of the Congress, to whom the Empire meant so much, gave a résumé of the contributions to the mining industry which were being made by the constituent parts of the Empire. The papers from the Institutes in Australasia, South Africa and Canada provided the details of resources and practice: while the individual contributions to the proceedings dealt with those phases of the mineral industry which are fundamental to the economic strength of British people, or to the health and well-being of the workers. While the subject matter thus presented was British mineral resources, and while the first consideration was the co-ordination and co-operation of British enterprise throughout the world, there emerged very clearly the wider viewpoint that the discussions had to do with a world industry, and with the contributions that that industry was making, and could further make, to the advancement of civilization irrespective of national boundaries, the world over. The invitations to representatives of the mining industry from the United States to participate in the Congress, and the warmth of approval which that participation evoked, were indications that such a congress cannot to-day be merely national in scope, and that trade in minerals, as in other natural resources, cannot be confined within national boundaries, but will seek its channels, unless artificial obstructions are too great, where the natural channels already exist.

Jan 1, 1925

By W. G. Jewitt

Introduction The use of the aeroplane in prospecting is already familiar to everyone connected with the mining industry. Apart from transportation companies, three organizations, the N. A. M. E., the Dominion Explorers, and the Exploration Department of the Consolidated Mining and Smelting Company, have made the aeroplane an everyday feature in every mining district in Canada. Its use has been demonstrated successfully in the mountains of British Columbia, but perhaps its greatest field lies in the Canadian Shield, where the numerous lakes and rivers afford an almost continuous series of landing places for aeroplanes, on floats in the summer and on skis in the winter. To the man who has travelled by canoe, toiling over fly-infested portages or held for days at a time, wind-bound, on the big lakes, the ease, speed, and cheapness of aeroplane travel have marked the beginning of a new era, in which ground previously covered with difficulty in a month or more is travelled with ease in a few hours. Development of an air service in the Consolidated Mining and Smelting Company has proceeded on different lines from those of other organizations, and this paper is concerned with that development.

Jan 1, 1931

"HPGRs operate in a wide array of applications in mining and minerals. These range from relatively coarse crushing of copper and gold ores at one end of the spectrum to the processing of fine iron ore pellet feed and fine industrial mineral products at the other. Traditionally these circuits involve the treatment of relatively moist materials in pre-grinding circuits; using single stage HPGRs in open circuit or as a closed circuit operation with screening or partial product recycle. More recently, HPGR is increasingly deployed in dry grinding in combination with air classification. The high throughput demonstrated by larger HPGRs has stretched the application towards coarser size reduction duties for a number of new projects. At the same time, the basic principle of inter-particle crushing for generating a product with a high fines proportion gives ground to investigate applying the technology further towards finished product duties. The advantages that HPGR brings are clear. Multi Stage grinding enables energy efficient size reduction across more of the comminution circuit. Primary HPGR serves for a coarse grinding duty, whereas a secondary HPGR is geared towards generating a fine product for downstream processing or even a finished product. This publication summarizes some of the features of staged HPGR circuits and discusses some examples of operating and projected applications.INTRODUCTION In most HPGR applications, the grinding units are used as a single process stage, either in open circuit, such as for pebble crushing [Rose 2002, Westermeyer 2000, Van der Meer 2015] or in closed circuit with classification [Van der Meer 2009, 2012] or product recycling [Van der Meer 2010]. Where a higher plant capacity is required, the HPGRs are commonly installed in multiple lines in a parallel arrangement [Parker 2005, Koski 201, Vanderbeek 2006]. HPGRs can take a wide range of feed size distributions, and grind this down to a product with a high fines content. In general view, there is a limit on the size reduction range that even an HPGR can provide. Grinding down from a very coarse ore (e.g. 70-100 mm) to a very fine product (e.g. 100 microns range) is stretching the ability of a single stage HPGR circuit. Fine grinding generally requires a classification stage that returns the classifier oversize to the head of the HPGR circuit. From one point of view, it can be demonstrated that when recycling a large proportion of fines and middlings back to the HPGR feed results in an effective feed with an overrepresentation of middlings and fines, which will eventually reduce the grinding efficiency and consequently result in an increased recirculation mass flow [Van der Meer 2014]. From another point of view the large recycling mass puts a strain or even a limit on the capacity of present-day conveyor capacity."

Jan 1, 2018

By P. W. A. Mayer

"As the push toward the northern regions of Canada steadily increases to exploit the rich mineral reserves, interest is steadily rising in respect to accessibility and climatic conditions and the problems posed thereby. In twelve years of operation, the Iron Ore Company of Canada, and associated companies, have found, through advanced technology, ingenuity and, most of all. need, some of the answers to the running of a profitable year-round open-pit mining operation."

Jan 1, 1966

By K. Soucek, J. Ptácek, A. Hastíková, R. Kukutsch, P. Konícek, P. Waclawik

"Cable bolts are used frequently as a secondary support system (with steel arch support) in difficult stress-strain conditions of deep coal mines. The load transfer mechanism of cable bolts depends on several factors, such as the strength, deformation and geometric properties of the bolts, resin and the surrounding rock mass so-called cable-resin-rock system (CRR system). The bonding length and bolt/borehole diameter ratio strongly influence the final bearing capacity of the CRR system.The study presents the behaviour of CRR system during a pull-out test which is usually used in the carboniferous rock mass in the Czech part of the Upper Silesian Coal Basin. A series of 28 pull out tests were performed on 3-m-long cable bolts, with various combinations of borehole diameters and bonding lengths, to understand this behaviour. Boreholes were drilled into a solid rock mass consisting of fine-grained sandstone to guarantee similar conditions during the pull-out tests. Video inspection and measurement of borehole diameters were performed to determine their quality and real diameters. Three characteristics were observed from pull-out test results: ultimate pull-out load; displacement of the end of bolt and system stiffness. Numerical modelling by FEM (Finite Element Method) was used to determine the stiffness of the CRR system for variable bolt/borehole ratios and bonding lengths each under constant load. A linear elasto-plastic model and a mohr-coulomb model were used for cable and resin-rock respectively. The results of the experiment may contribute significantly to improving of the methodology of cable bolts installation as well as the design of used cable bolts."

Jan 1, 2015

By P. Patnaik, F. Cuneo, D. M. Wang

Microwave (MW) energy has been used widely for several decades for communications, food processing, wood drying, vulcanization of rubber and medical therapy. Recently, this technology was found to be capable of successfully sintering ceramic and metallic powder materials, with the advantages of reducing soaking times and sintering temperatures. Unlike conventional heating, MW radiation works through the absorption of the microwave energy by a material placed in an electromagnetic field within the microwave cavity. A far more efficient heating process is produced due to the unique ability of microwaves in selectively heating a pecific part of the material with desirable dielectrical properties. This exploratory research was initiated with the objective of locally sintering the thermal barrier coating of gas turbine components using MW radiation. This novel technique may allow repairing of the component without subjecting the entire piece to unnecessary elevated temperatures and reduction of process time and cost. Y ttria stabilized zirconia was used in this study and sintering was conducted using a multimodal 1.2 kW microwave facility. Three configurations of heating setup were experimented and the preliminary results will be discussed in this paper.

Jan 1, 2006

By L. Xia, B. Hart, K. Douglas

In the flotation of Rare Earth Element (REE) bearing minerals, oxalic acid is reportedly acting both as a depressant and pH modifier. Testing has established the significance of oxalic acid in the flotation process however its specific role in either the recovery or selectivity of REE over their gangue minerals is not well understood. Pulp pH reduction trials with alternative acids have not shown the same effect on the REE mineral recovery or the depression of gangue phases. This work examines the effect of oxalic acid on the surface of gangue minerals (quartz and carbonates (dolomite and calcite)) in a series of conditioning tests. Gangue surface analyses by TOF-SIMS indicate that oxalic acid inhibits the transfer of secondary ions generated during the conditioning process from one mineral phase to another. In this regard, the oxalate anion acts to fix ions in solution through chelation, limiting their participation in surface adsorption.

Jan 1, 2014

By W. G. McBride

THE present demand for men with engineering training exceeds anything in the history of the profession. Recent estimates indicate that mechanization of war has reached such a stage that at least twelve horsepower is required now for every one horsepower needed to run the machines of the first Great War. The scale of operations exceeds anything in the past, while more territory and people are involved than ever before. Many of our allies have inadequate or no facilities for producing the thousand and one articles absolutely necessary to the conduct of modern warfare. Lack of preparedness has made it necessary to produce at an unparalleled rate to gain parity with the enemy, while our losses have been so heavy that replacement, in itself, presents a task which might well stagger less courageous peoples. This means that not only is there an unprecedented demand for engineers to produce the machines, munitions, and supplies of war, but there is a correspondingly large need for men with engineering skill in the uniformed forces to operate and maintain the vast numbers of ships, 'planes, tanks, trucks, radios, and a myriad of other devices to carry on the varied activities of war. This abnormal demand came upon us after almost ten years of stagnation in the engineering industries. During this time many trained engineers drifted into other callings, while the lack of jobs for graduates caused a falling off in the number of men training for this profession. Consequently, the supply of well trained engineers was below normal when the madman of Germany precipitated us into the present turmoil. Added to all this, we in Canada are still suffering from governmental inefficiency in the utilization of the available supply of engineers. In the armed forces, engineers have been assigned to office and other work where their engineering training is not only wasted but for which men with more suitable training could be found. Mining engineers are debarred from service as aeronautical engineers, and students in mining engineering are denied the bursaries provided for aiding students in engineering. Mining and metallurgical engineers are both barred from the Ordnance department of the army. This arises from a misunderstanding in relation to engineering training. In Canadian engineering schools, all engineers are given a sound training in the branches of human knowledge which are fundamental to engineering: mathematics, physics, and chemistry. The basic difference between the several categories of engineers lies in the fact that training in the application of this fundamental knowledge to the solution of engineering problems is given in different subjects.

Jan 1, 1942

By L. A. Anestiev

A method based on use of calorimetric data for the determination of solidification kinetic parameters is proposed. The method incorporates recent theories of nucleation and growth and allows modeling heat fluxes observed in calorimetric experiment. Statistically optimal estimations of the kinetic parameters, which include the activation's energies of nucleation and growth, are derived from experimental data by means of nonlinear regression analysis. The method is applicable to pure substances and alloys. The evaluation of the kinetic parameters characterizing solidification of pure Al is used for clarifying and exemplifying the method.

Jan 1, 2004

By J. M. Cummings

The importance of controlled sand properties to the production of quality castings has been recognized by foundry men for many years, but the maintenance of requisite standards results in a relatively high sand consumption, which in steel foundries, for instance, may range from half a ton to over one ton of sand per ton of finished casting. During the war, obtaining and maintaining adequate sand supplies became a serious problem in many foundries, owing to increased wartime production and serious 'bottlenecks' in transportation. As a result, considerable interest was aroused in the possibilities of various sand reclamation systems by which up to 85 or 90 percent of discarded sand may be returned to a usable condition. During the past five years or so, a number of sand recovery installations have been made by both ferrous and non-ferrous foundries in Canada and the United States, and have resulted in substantial reductions in sand costs in every case. The possible benefits of sand reclamation are particularly apparent in British Columbia where no suitable sands for steel and heavy iron foundries occur naturally, and where freight costs on imported sands are considerably higher than initial selling prices. This is well illustrated by the fact that silica sand, which sells for about $2.00 per ton at pits in Illinois, is laid clown in British Columbia for around $11.00 or $12.00 per ton. The operating costs quoted for certain of the reclamation schemes, i.e. $0.25 to $1.50 per ton, may actually be no higher than the cost of waste sand disposal in city-located foundries. In view of the foregoing considerations, the British Columbia Research Council has undertaken a study of the possibilities for sand reclamation, with particular attention directed to its application in local steel foundries. No commercial occurrences of silica sand are known in the Province, and, with this in view, the Council previously investigated the possibility of recovering silica sand from local impure sands. Results were definitely encouraging, but it was felt that the present market is too small to permit economical production by the method developed.

Jan 1, 1947

By S. Bantubani, I. Mc Dougall, S. Arjun, H. Joubert, R. Hansraj

The requirements determining the design of the Söderberg electrode columns used in base metal applications are different to those of other industries. There is a strong trend to position the contact shoes above the furnace roof in order to reduce the risk of water leakages directly onto the furnace bath. Tenova Pyromet has adapted its proven electrode column design for application on base metal electric furnaces based on these requirements. The design modifications implemented as well as considerations regarding the overall electrode-roof-furnace arrangement are discussed. Equally important is the management of the Söderberg electrodes to prevent over or under baking. Tenova Pyromet has developed the AutoFurn™ furnace controller to not only optimise furnace operations, but to improve electrode management. An overview of the electrode management control philosophy implemented by AutoFurn™ is provided, focusing on intelligent electrode regulation, slipping and baking. INTRODUCTION Tenova Pyromet has developed an electrode system for use in base metal furnaces, which builds on the experience that Tenova has gained during the past 30 years with electrodes in the ferroalloy and base metals industries. In base metals applications, an important safety consideration is the minimization of water within the furnace and on the furnace roof. In addition, direct contact between copper equipment such as contact shoes and pressure rings and the contents of the furnace is discouraged. In a 3 phase AC furnace, three electrode columns transfer the electrical energy to the furnace bath. Both Söderberg and prebaked carbon or UHP graphite electrodes are in use in base metal furnaces. In each column, the electrode is held in position by a hydraulic slipping and regulating device, a pressure ring and contact shoes. The electrodes can operate in a submerged-arc or brush-arc configuration, where the electrode is immersed in the slag or a short distance above the slag (Mc Dougall 2013). The electrode equipment is divided into an upper and a lower electrode assembly. The self-baking Söderberg electrode is made from lengths of steel casings that are added to the top of the electrode column and welded into place. Carbon electrode paste is added to the inside of these casings and is baked to form a solid tip in the region of the contact shoes. The working platform that surrounds the area where new electrode casings are added, is electrically isolated from the building and each electrode is isolated from the others to ensure the safety of the personnel who perform the electrode casing additions.

Jan 1, 2019

By G. Ergin

The interactions taking place between Al-Mg alloys and the bed media during aluminum filtration are not yet well understood. These interactions were studied using the infiltration technique. The reaction interface was analyzed using different techniques such as SEM and TEM. Only spinel formation was observed at the interface regardless of the type of alumina and contact time. This paper discusses the results of the study.

Jan 1, 2004

By T. G. Phillips

"This paper gives an inside look at a bulk terminal and describes the preparations that must be made by a company in developing such a terminal and its position in today's traffic pattern. The following headings cover the subject material: (a) Traffic pressures, their detection and measurement, (b) position in the traffic flow -selection of site, (c) transportation connections -present and possible future routes, (d) engineering studies and costs, (e) contracts, the basic material for insured traffic, (f) financing, (g) budgetary control, (h) development of new techniques, (i) growth into new cargoes or cargo-handling methods and (j) consolidation."

Jan 1, 1968

By M. Ataka

Magnesium alloys are not easy to plastically deform at room temperature and may suffer from edge cracking at high reductions, especially during sheet rolling. In this study, the authors attempted to improve the rollability by the low-temperature hot rolling method, in which the rolling temperature range is lower than that of hot rolling, and also by the edge-heating method, which locally heats sheet edges.

Jan 1, 2006

By P. Latostenmaa, T. Veneranta, J. Järvi, E. J. Peuraniemi

Boliden Harjavalta has operated a copper flash smelter since 1949 thus the smelter celebrates 70th anniversary of flash smelting in 2019. This paper shortly describes the historical perspective of the smelter and gives an update of the current operational issues and process modifications made during the recent years. The plant has carried out several major investments lately providing a firm view on the future. A new landfill area for the final slag was commissioned in 2018. A modernization of the concentrate storage area, a new acid plant and a debottlenecking project of the smelting line have been recently commissioned. At the same time, the tankhouse capacity will be expanded. This paper focuses on smelter modernizations. INTRODUCTION Boliden is a metal company operating mainly in northern Europe with core competencies in the fields of exploration, mining, smelting and metal recycling. Boliden Harjavalta, located in Finland, is part of the Smelters Business area of the Boliden Group and operates a copper and nickel smelter with related sulphuric acid plant in Harjavalta, and a copper refinery in Pori. As a short historical review, Harjavalta’s history may be dated back to the year 1910 when the Outokumpu ore body in eastern Finland was discovered. By the end of 1913, a copper mine was in operation and a copper plant based on Hybinette process was ready for commissioning. Due to difficulties in metal recoveries and throughput the Hybinette process was permanently shut down in 1929, and 100% of the mining production was sold as concentrate abroad. As the mine production increased steadily, a decision of a new smelter was made in early 30’s. In 1936 Outokumpu’s copper smelter based on electric smelting was commissioned in Imatra. The smelter was dismantled and transferred to Harjavalta during the final stages of the Second World War. The copper refinery started in Pori already in 1941 and the first copper anodes were cast in Harjavalta in 1945. First sulphuric acid plant started operation in 1947. Due to the post-war shortage of electrical energy, the plant metallurgists initiated a major development work to start exploiting the latent heat of concentrates. Thus, the flash smelting method was developed in Harjavalta and commissioned in 1949. Ten years later, flash smelting was also applied for nickel concentrates. Table 1 summarizes major historical and technical milestones of Harjavalta. The history of flash smelting is described in details in another paper of this conference (Jåfs et al., 2019).

Jan 1, 2019