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"With the globalization of the mining industry, many companies are now seeking to invest in underground diamond mines, with the purchase of small diamond pipes being seen as particularly attractive. However, recent experiences in South Africa have shown that many projects fail due to a lack of awareness of the hazards associated with diamond mining. In this paper three significant hazards are dealt with — mud rushes, block crushing, and implementation of an inappropriate mining method. Measures that assist in the prevention of these three hazards are given.IntroductionFor over a hundred years, South Africa has been seen as the centre of the diamond mining industry, possibly having the largest number of operational underground diamond mines in the world. Despite the fact that this industry has been dominated by large mines of De Beers Consolidated Mines Limited, many small underground mines have operated profitably for a number of years, exploiting diamondiferous fissures and pipes. In the last decade there has been renewed interest in these small operations from international companies. However, many of these projects have not realized their full potential owing to a lack of appreciation of the hazards inherent in the operation of a diamond mine.Hazards Associated with Diamond MiningIn the development of a diamond mine, the mining company must be aware of the hazards associated with diamond mining. There are three main hazards: (1) mud rushes; (2) block crushing; and (3) selection of an inappropriate mining method (not a natural hazard, but a planning induced hazard). Each of these hazards will be dealt with in turn in the following sections."

Jan 1, 2000

CAT offers three different methods to accomplish crowd & retract on an electric rope shovel Rack and pinion Rope crowd HydraCrowd The presentation will compare the three systems and introduce the benefits of the Hydracrowd

May 1, 2013

By J. Dubinski

This paper describes the key circumstances of the underground coal gasification (UCG) process, which is planned to be carried out in the Polish hard coal mine ?Wieczorek?. The construction and field tests of a UCG pilot plant have key issues that need to be addressed to realize the research project goal: the elaboration of a highly effective technology of fuel and electricity production. The project will conduct several monthly tests of gasification in the pilot geo-reactor, which will be constructed based on the results of laboratory tests. The realization of the process requires numerous appropriately prepared actions adjusted to natural conditions in the hard coal deposit. Based on scientific principles, it is necessary to elaborate the procedures related to the location of the UCG installation (including its legal and safety aspects), and to perform a technical risk analysis. In addition, it is necessary to determine the required mining, geological, technical, economic and organizational circumstances, while at the same time considering the real but constantly changing process conditions.

Aug 1, 2013

By Adam Turcotte

Mining operations consume a considerable amount of energy, and while reduced energy consumption is desirable, it is not always clear how to achieve this goal. Understanding the opportunities to optimize energy consumption is crucial, and the key to understanding is visualization. One option is the Sankey diagram, which has been used for over 100 years to visualize the flow of energy, materials, or cost through various processes. However, there are drawbacks to this approach that must be addressed. In a Sankey diagram, each flow is represented by an arrow possessing a width proportional to the magnitude of the flow it represents. The diagrams show input flows, how energy is converted and into what form, and also output flows. As per the first law of thermodynamics, the total energy output is equivalent to the total energy input, so any energy that is not transferred to another process is considered to be wasted. These waste flows are depicted in Sankey diagrams and make it straightforward to associate energy sources, sinks and waste flows. Unfortunately, Sankey diagrams do not convey all information required to support practical decision making for redirecting individual energy flows. Based only on a Sankey diagram, it may become evident that a significant flow of waste heat is of the appropriate grade (temperature) and volume to meet an on-site heat demand currently being met with paid-for, possibly carbon intensive fuel. However without augmenting the Sankey diagram with 3D spatial, true geometric analysis, the practicalities of the concept or idea may not be fully appreciated. Another issue with a Sankey diagram is that the magnitude of the energy flowing between processes may have temporal fluctuation or variability on different timescales (diurnal, seasonal, interannual). Currently, Sankey diagrams only provide a static picture of energy conversion and consumption, so that, for example, 4 separate diagrams could have to be prepared for each season. A new energy flow visualization technique which we have called Sankey Trees has been developed. Process locations are defined within a 3D model of the site being studied, and the magnitude of the flow between each pair of processes considered is replaced with a time series. Branches of sustained and diminishing flows are represented through variation of the geometric properties of the branches of the trees. These branches are animated to indicate the direction of flow, and branch joints are used to indicate that a process is transporting one form of energy to multiple processes.

Aug 1, 2013

By Gaston Giuliani, Jérome Massot, Didier Bourlès, Lionel Siame

"Abstract - We present a new approach for the evaluation of the potential of emerald reserves in gem projects using beryllium (Be) mobility. The distribution of Be in the different phases of hydrothermally altered (albitized) black shale hosting Colombian emerald deposits indicates that Be mobility is associated with the breakdown of Fe-Mn oxyhydroxide phases. The amount of Be that can be mobilized (~0.7 x 10-6 g/g; i.e., 0.7 ppm) may represent up to 18 wt% of the total Be contained in the black shale. A mass balance calculation applied to a well-constrained alteration zone of the Chivor mines, and based on the quantification of Be that can be mobilized under hydrothermal conditions, gives an estimate of the total gem reserves of these mines. Resumé - Une nouvelle approche, basée sur la mobilité du béryllium (Be) pour l’évaluation des réserves d’émeraude dans des projets d’exploitation de gemmes est présentée. La distribution du Be dans les différentes phases minérales de schistes noirs hydrothermalisés (albitisés) qui contiennent les gisements d’émeraude colombiens, indique que le Be mobilisable se trouve dans les oxyhydroxydes de fer et de manganèse. La quantité de Be potentiellement mobilisable (~0,7 x 10-6 g/g; soit 0,7 ppm) constitue jusqu’à 18% poids du Be global contenu dans le schiste noir. Un bilan de masse appliqué à la zone d’altération hydrothermale des mines de Chivor et basé sur la quantification du Be mobilisable, donne une première estimation des réserves à émeraude de ces mines. rieur."

Jan 1, 1999

By Morris J. Viljoen, David R. Young

"The zone of economic interest at H.J. Joel Gold Mine is the VS5/Beatrix Composite Reef, a quartz-pebble conglomerate of Archean age. The reef occurs at the base of the Eldorado Formation, Central Rand Group, of the Witwatersrand Supergroup. At least three stratigraphically distinct conglomerates form this economic zone. In order of deposition these are the Footwall, Beatrix, and the VS5/Beatrix reefs. The Footwall and Beatrix reefs are equated with the Aandenk Formation with transport directions toward the northwest, whereas the VS5lBeatrix Reef is of Eldorado age, with transport directions toward the south. The change in the drainage direction was caused by a major basin-wide tectonic event that occurred prior to the deposition of the Eldorado Formation. The Beatrix Reef was formed in a proximal, braided, fluvial environment by a process of aggrading gravel bars between channelways. The VS5/Beatrix Reef was formed by the desegregation of pre-existing Beatrix Reef with the introduction of new material containing much shale detritus and is seen to have been deposited in a more -distal, braided, fluvial environment, similar to the Beatrix Reef.The average gold concentrations are different for each conglomerate; the Beatrix at 32.1 ppm Au, the Footwall at 24.4 ppm Au, and the VS5/Beatrix at only 12.4 ppm Au. A sedimentary gold concentrating process related to higher energy braid channels was primarily responsible for these high gold grades. Not only the basal unconformity surface, but also, internal degredation surfaces, were prime sites for concentration. An understanding of the spatial distribution of these differing conglomerates and their braid channels forming the economic reef zone is necessary in predicting ore grades for future mining."

Jan 1, 1994

By H. M. Roscoe

Fifty per cent. increased lump coal production and at the same time a reduction of from 20 to 40 per cent. in explosive consumption. These results were achieved by the use of the rock-dust cartridge method of stemming shots in the Ruhr coal mines, as announced by Dr. Alfred Stettbacher in the September 1923 number of the Explosive Engineer. Immediately, the explosive and the coal-mining industries on this continent became intensely interested. Considerable experimental work has been carried on in a number of American and Canadian mines during the past year, by which our engineers have become assured that the use of rock-dust cart-ridges for stemming shots increases the efficiency of explosives and promotes safety in coal mines.

Jan 1, 1924

By F. Rosenblum, P. Spira

"A correlation has been established between the oxygen demand of Brunswick Mining and Smelting ore and flotation results at the bench, pilot plant and operating plant scale. A method of dete""1llining the aeration requirement of sulphide ores on the basis of this correlation is presented. It is shown that abraded iron from grinding media plays an important role in aeration and flotation. Laboratory grinding must therefore be conducted under controlled conditions with suitable grinding media in order to obtain the true aeration requirement of the ore.A method of evaluating aerator efficiency, also based on oxygen demand measurements, has been used successfully at Brunswick Mining to design pilot plant and full-scale aeration systems.1. IntroductionPre-flotation aeration of sulphide pulps has been practiced in the Noranda Group for many years to help in the depression of pyrite and pyrrhotite and to promote chalcopyrite and/or galena. Recently, two out of three parallel circuits at the Brunswick Mining and Smelting Corp. Ltd. concentrator have been converted on a test basis to a new flowsheet incorporating aeration as a basic step. Among other benefits, a substantial decrease in the middlings load has been achieved as a result of improved pyrite rejection. There has been increasing interest in other organizations in the potential advantages to be derived from' aeration in terms of improved metallurgy and/or decreased reagent consumption."

Jan 1, 1978

By Andre Vien, D. H. Hendriks, D. Willet, B. C. Flintoff

"For many years the training of mill operators was an informal process which involved senior operators training junior operators on an as-needed basis. Recognizing the needs and benefits of better training some companies, and even some provinces through legislation, have moved to ensure that a formalized training program exists in the plants. These programs tend to focus on basic safety and operations. Much remains to be done. With the more rapid incorporation of new processing and information technologies, and the goal to keep labour costs to a minimum by doing more with less, operator training has become a critical issue. This paper briefly examines the evolution of training programs, provides some measure of their effectiveness, and explores some recent developments which could have a very significant impact on the industry.PreambleOne can draw an analogy between operator training and the mechanical support of production equipment. When we buy a piece of process equipment it is critical that the mechanical installation be done properly to ensure that the device will operate at peak performance on start-up. Once the equipment is running, some form of preventive maintenance is required to ensure continued efficient operation. The operators and the equipment are both elements of the processing system, yet the former do not seem to get the same ""start-up"" or ""operating"" support. Are they not seen as critical to efficient operation? Why is this so? What impact does it have? How can we improve?These are all very logical and important questions, although the answers are not nearly so obvious. In the mineral processing industry, progress in operator training over the past thirty years has been limited and quite variable. To address the perceived need for a more coherent and consistent approach, some provinces have moved to incorporate basic training requirements in their legislation. Some plants have gone a few steps further by building integrated training programs into their operating culture. One conclusion which can be easily reached is that there are no standards, and that the range of training activity is great. In other words, a flotation operator is not a flotation operator is not a flotation operator. Their knowledge and skills are very much a function of training and experience, which are clearly corporate and site specific."

Jan 1, 1994

By Alim Ullah

Danieli entered into the Direct Reduction (DR) field in order to offer its clients complete turnkey facilities for steelmaking?from processing of raw materials through finished products. The Danarex® Process produces a passivated product, called the Supermetallic (SPM), without hot-briquetting. One of the main features of the Danarex® Process is its ability to produce approximately 50% of the Direct Reduced Iron (DRI) through reduction gas generated in a reformer and another 50% through recycling preheated furnace exit gas. Some other distinguishing features are: separation of carburising and cooling zones and the use of double bustle for better distribution of gas inside the shaft furnace. A pilot plant was set up at Hazen Research, Inc., Golden, CO in order to show that the integrated process works as expected and to obtain process data. The SPM obtained was of a very high quality, evidenced by metallization levels of 92% to 98%. The carbon content could be controlled between 1.5% to 4.0% by varying the operating conditions and approximately 75% of this carbon was present as Fe3C. The product was tested for inertness by Chilworth Technology, England, using UN standard tests and was found to be safe for outdoor storage and transportation.

May 1, 2003

By J. Ellis Thomson

For many years the value of qualitative microscopic investigation has been recognized in both of the fields of pure and applied science. In particular, its aid has been invoked in the determination of rock specimens in thin section, and some at least of the interrelations of minerals present in any one section have been observed and, to a limited extent, applied for the solution of different problems. During the past decade this form of research has also been diverted to the determination of ore minerals in polished section, with some observation of their structural relations. Microscopic research of a quantitative character, on the other hand, while started nearly one hundred years ago, has found but a limited application in petrography and has scarcely been used at all in the more modern science of mineragraphy. This is very largely due to the methods employed, since most of them consumed too much time and were, in addition, too laborious to encourage many workers in their use. The details of procedure for these earlier methods will be found in another paper by the writer, and will be omitted from this discussion as being of small interest to practical mining men.

Jan 1, 1930

By Louis Tellier

SIDBEC commenced detailed planning of major capital expenditures to install integrated steelmaking facilities in 1969. Today, less than IO years later, SIDBEC and its subsidiaries have completed major mining, concentrating, pelletizing, direct reduction ? electric furnace steelmaking and continuous casting plants. The total cost of these projects was almost 1 billion dollars. The philosophy behind the project planning and the evolution of management control are explained. These extensive projects were undertaken during a period of exceptional inflation and a disturbed labour climate, but were nevertheless completed with only modest overruns, with good control of timetables and with exceptionally good start-up performance. Project planning, relations with consulting engineers, introduction of new technology, purchasing and field management and cost control are discussed.

Jan 1, 1979

By P. Cielo

"Nondestructive inspection is an important quality control tool in the material processing industry. Being nondestructive, such a control may be applied to the whole production, as long as the available techniques are fast and easily automated. Ideally, nondestructive testing (NDT) methods should operate in a noncontact configuration in order to be deployable on-line with minimum perturbation of the production process.After a short introduction to the most common NDT techniques, with particular emphasis on ultrasonic, radiographic and electromagnetic methods, a few new approaches which are under development at the Industrial Materials Research Institute, (Boucherville, Quebec), are reviewed. Noncontact techniques such as laser ultrasound, thermoelastic and thermographic methodologies will be described, and their applications to materials of industrial interest will be discussed."

Jan 1, 1989

By Ted Nuorivaara

The use of polymer-surfactant mixtures as foam stabilization agents is a topic that has drawn the attention of several fields but has so far not be thoroughly studied in the context of mineral froth flotation. The present work showcases a study on the impact on flotation performance of cellulose surfactant derivatives and their mixtures with commercial frothers. Bubble size and foam property measurements were run in a two-phase system along with laboratory-scale flotation experiments conducted using a porphyry copper ore from a mine in Finland. A comparative analysis on recovery, grade and flotation kinetics is presented on the products obtained using: i) a partially hydroxylated cellulose derivative (i.e. hydroxypropyl methyl cellulose; HPMC), ii) a commercial polyglycol-ester frother (Nasfroth240; NF240), and iii) mixtures of these two. The results show that using frothers with a total concentration of 30 ppm, the HPMC-NF240 mixtures provide advantages in terms of Cu recovery, (i.e., up to 95%), compared to the use of either NF240 (ca. 76%) or HPMC alone (ca. 1%). Interestingly, only a small proportion of HPMC mixed with NF240 was sufficient to produce a measurable increase in recovery. This improved performance was attributed to a synergistic effect of the polymer-surfactant mixture which further reduced the bubble sizes in a two-phase system compared to that of NF240. The present work offers a further step into understanding the phenomena taking place when a short chained surfactant is either substituted or mixed with a cellulose derivative, offering potential ways of exploiting this behavior for the enrichment of minerals. INTRODUCTION Froth flotation has been the predominant technology used to beneficiate sulfidic copper minerals such as chalcopyrite ever since it was invented in the late 19th century. The reason for the domination of flotation technology lies behind its versatility in selective separation as well as relatively cheap operational costs (Wills & Finch 2015). Even though flotation of sulfidic copper minerals is moderately well understood based on the broad research work done around the subject (e.g., Albijanic et al., 2015, Bournival et al., 2017, Wang et al., 2015, Mikhlin et al., 2015, to cite only a few), the modern era presents new challenges to the primary raw material industry, including questions regarding sustainability of mining operations accompanied by a need to improve the process efficiencies due to declining ore grades (Edraki et al., 2014).

Jan 1, 2019

The dissolution of chalcopyrite has received a significant amount of attention. The predominant paradigm of investigation is that its rate of dissolution is limited or passivated by a surface coating or film of material. The common candidates for such a passivating coating are numerous: polysulfide coating, metal deficient layers, copper sulfide coating, bornite layers, jarosite precipitates, and elemental sulfur films. While this line of explanation, that is, the explanation based on passivation, seems to have won some form of consensus with researchers, there is another explanation for the results that can account for all the results observed. Crundwell (1988) proposed that the solid state properties of chalcopyrite, in particular, the semiconducting properties, are responsible for the observed behaviour of chalcopyrite. The purpose of this paper is to outline the semiconductor mechanism of dissolution, and to show how this mechanism accounts for all the observed phenomena recently reported in the literature. The paper outlines the semiconductor mechanism of dissolution, shows how this mechanism accounts for the dissolution

Jan 1, 2014

By Mark Liskowich

When is it the proper time to initiate engagement with various stakeholders, including Indigenous communities? This paper will demonstrate what stage of a project’s evolution is the appropriate time to initiate a stakeholder engagement plan. It will look at aspects to consider when identifying the communities to involve. It will describe the contents of a Stakeholder Engagement Management Plan as well and touch on how tried and true options analyses, such as a Multiple Accounts Analysis can be used to inform the results of the engagement, guide the development of your project and clearly document the engagement process. It will illustrate the benefits of initiating engagement at the appropriate point in your project’s schedule, and the limitations of doing so too early and at later stages of the project engineering. The benefits of this approach can be realized within any legislative Jurisdiction including the Canadian Environmental Assessment Act 2012 and Canada’s new Impact Assessment Act.

Jan 1, 2020

By S. Yadav, T. G. Murthy, C. Saldana

"An experimental study has been carried out in order to study the deformation of porous brittle materials under plane strain indentation. Gypsum, which is well known model system for understanding the behaviour of soft rocks, is used in this study. The effect of wedge angle is investigated in this research through this series of experiments, using wedges of 3 different apical angles. High-speed, high-resolution images are captured using a CMOS camera during the experiment. The images obtained are analyzed using a Particle Image Velocimetry (PIV) algorithm in order to obtain the evolving velocity, strain-rate and strain fields.INTRODUCTIONThe problem of indentation, which is usually referred to in the context of hardness testing is ubiquitous as a material characterization technique for a large class of solids. Mechanical properties of materials such as yield stress, flow stress, fracture toughness, elastic moduli etc. can be related to the hardness of a given solid. The indentation problem involves a given material or solid (whose properties are to be determined) indented by a relatively harder material (indenter) allowing the solid to undergo plastic deformation, which is then related to the yield stress of the material. The problem of indentation and its variants see many applications ranging from mining and petroleum industry, infrastructure industry, manufacturing, and biomedical sectors. Indentation has been extensively studied in metals, with accurate measurement of deformation parameters, stresses and comparison with analytical solutions. On the other hand, understanding of indentation in other class of solids such as cellular solids, porous solids, rocks, and soft solids is still nascent. In case of rocks, a comprehensive understanding of the indentation problem is very crucial because of the obvious applications in mining, petroleum and infrastructure sectors. The inherent porosity, the brittle nature of the rocks, adds to the complexity of indentation in these porous brittle solids. Various theoretical models with degrees of simplifying assumptions have been proposed to study the indentation in rocks. The most common model used in the study of indentation in rocks is a cavity expansion model, wherein a blunt indenter indenting into a rock is approximated with the expansion of cylindrical or spherical cavity in an elastic-plastic material. Complementary studies in understanding fracture initiation and propagation due to indentation has been largely based on the studies of traditional brittle materials such as glass."

Jan 1, 2015

By L. Shasko, M. Hurlbert

As climate change is increasingly perceived as a problem, and fossil fuel based power production options are increasingly limited through regulatory restrictions and public distaste, future options become constricted. Reflexivity and social learning elicited through qualitative and mixed research methods offer important insight into what future power production pathways might be. Given factors of cost, baseload requirements, and energy density, options such as nuclear may be increasingly accepted. This paper explores this literature and possible methods of pursuing the reluctant acceptance of nuclear energy.

Jan 1, 2020

By D. M. Watson

Mineral discoveries and subsequent extraction have led to the establishment of many small communities, some major towns and a few cities . In Canada, such developments have essentially occurred without benefit of long-range regional or local planning. In the past, this was not a cause for concern. Now, however, rising expectations and reorientation of social values have placed increasing responsibility on government and industry to ensure the long-term viability of communities and regions. Such responsibility means large investments by government in infrastructure and by industry in extractive and processing plants. Uncertainty in the interpretation of ore reserve estimates becomes a critical factor. The traditional methods of reporting reserves - "proven", "probable" , "possible" - may be useful in individual mine production planning, but they are inadequate for planning industrial and public infrastructure, The need for a better information base is critical, with clear and precise definitions of what is being reported, but we are a long way from achieving it. The challenge is therefore to develop a closer professional relationship between government and industry and to tie mineral development to long-range regional strategies.

Jan 1, 1977

By Donald J. Farrish

"Mr. Chairman and fellow CMP members, most of these remarks will be made with particular reference to copper concentrate but the basics apply generally to other metal concentrates as well.For very good reasons, using copper as an example, smelting capacity usually is located either close to mine production or close to areas of high copper consumption. The mine producer can add on smelting capacity to insure that the copper in his concentrate can be processed into a marketable form under more or less controlled conditions including costs. On the other hand, the consumer wishing to assure a better supply of copper likewise can build smelting capacity and offer treatment charges attractive enough to discourage mines from investing in their own facilities. In this regard, freight is an important factor. Bulk shipments from the heart of Africa with a large overland component are uneconomic whereas concentrate movements from Australia or South America compare favourably with smaller metal shipments.A mine project which incorporates smelting capacity, will often, through the presence of this capacity, encourage active exploration and development of additional concentrate production in the vicinity. The usual result is that new mines within reasonable distance of the smelter will be able to avoid the capital required to build their own smelting and refining facilities and that the existing facilities will expand to appreciate economies of scale."

Jan 1, 1978