Search Documents

By Tyler Rockley, J. P. Remi Proulx, Ruilin Yang

A highwall blast vibration project was carried out to quantify the level of blast vibrations produced from a trim blast in soft rock and a combined production and trim blast in hard rock. Combining production and trim blasts could be performed without exceeding the mine’s vibration limits.

Feb 1, 2020

By J. Labuschagne

The primary factor contributing to the profitability of a platinum mine and its associated concentrator is the time taken from the first hoist of material from underground to the first batch of concentrate shipped. To minimize the time it would take to produce concentrate without stopping because of a lack of feed material a project was undertaken to integrate the mining model with a concentrator production schedule () in the most capital-effective manner. A secondary goal was to ensure detailed stockpiling requirements, as the concentrator is in an area where ?visual pollution? is to be avoided. To achieve this a dynamic stockpile model was created utilizing the mine production schedule resolved into a daily production figure. Four different concentrator development models were then proposed. The difference between the mine production and concentrator consumption was integrated over the life of the mine to provide the accumulated stockpile tonnages for both Merensky and UG2 ores. The stockpile levels were never allowed to fall below zero to prevent a situation where the concentrator was operational without feed material,. When a development option was selected, the standard metallurgical performance calculations were used to derive a concentrate production schedule, that was then used as a basis for commercial concentrate sale negotiations.

Jan 1, 2012

By W. R. Crane

Mining of the red iron ores of the Birmingham district, Alabama, has _gone on energetically for the past 50 years and has created a large iron and steel manufacturing center, the only important one in the South. The district produces about 10 per cent of all the iron ore mined in the United States and 80 per cent of the Alabama output is red ore ; moreover 43 of the 419 blast furnaces of the country are in the district tributary to Birmingham and produce 7 per cent of the pig-iron output. The rapid growth of the district has been made possible by investigations that have led to radical changes in furnace practice; studies of methods by which the low-grade, highsilica ores may be treated by concentration 1 will give still greater impetus to development. The· mode of occurrence of the ore has made mining practice comparatively simple, but with the rapid extension of the workings underground and the disturbed condition of the ore bed some distance from the outcrop, conditions tend to become more difficult. Stoping, handling, support, drainage, and ventilation are all affected, sometimes favorably and sometimes adversely, by the extended workings and increased depth of cover. Should beneficiatioil make available the high-silica ores of the lower bench of the Big Seam, mining practice must necessarily be adapted to the new conditions and will be rendered more difficult as the weight of cover increases at long distances from the outcrop. The support of workings will require more attention as the weight of cover increases, and the efficient and economical operation of the mines will depend largely upon improvements in mining and handling the ore.

Jan 1, 1927

By D. E. Shanks

The Bureau of Mines surveyed a variety of inorganic ion-exchange materials to determine their suitability for removing valuable accessory elements and troublesome contaminants from metallurgical process and waste streams. Most of the materials, which included molecular sieves, heteropolyacid salts, and hydrous metal oxides, did not give adequate separations, did not have the necessary stability in strong acids or bases, or were not in a physical form suitable for ion-exchange use. Many of the suitable inorganic materials, especially the hydrous oxides, were capable of cation exchange with high capacity only in basic conditions, which caused hydrolysis of most of the cations tested. Multivalent anions, such as arsenate and phosphate, were easily removed from acidic solutions by hydrous oxides. Hydrous zirconia was the best material for this purpose. Multivalent anions were not easily des orbed because of compound formation; therefore, conventional ion-exchange techniques could not be employed. As an alternative approach, hydrous ferric hydroxide was used as a filter material to remove arsenate and phosphate from acid solutions. One gram of arsenic was removed from solution for each 20 g of ferric hydroxide. Ferric hydroxide is preferable to hydrous zirconia for use as a filter material because of low cost.

Jan 1, 1983

By Y. Béliveau

Emission of perfluorocarbon gases, CF4 and C2F6, produced during anode effects from aluminum electrolytic cells are a significant part of the total equivalent CO2 emitted by aluminum plants. With the current concerns about global warming, the reduction of these PFC gases is a key issue in reducing greenhouse gases for a smelter and achieving GHG emission agreement goals. This paper will present the approach taken by the Alcoa vertical-stud Soderberg plant in Baie-Comeau to reduce GHG emissions generated during anode effects and close emission gaps with other Alcoa Soderberg plants. The approach has been to adapt the existing technology in place at the Baie-Comeau Soderberg plant. PFC emissions were lowered by reducing both the anode effect duration and frequency through different methods. Examples of change include: implementing skimming practices and wider side crust break area for better alumina dissolution in bath, increasing the ratio between reacted and pure alumina, reducing the time to declare anode effects in the potrooms, implementing best work practices and finally educating the workforce on the importance of reducing PFC emissions.

Jan 1, 2007

The response was good-one of the best the SAIMM has had to its various questionnaires. 231 replies were received from 2768 members representing a response of 8,35%. For fellows and Members together, the response was 13,7%. The spread of responses based on respondents' work situation appeared to be well balanced with some bias from those in consulting organizations. Members' perceptions of their employers' positions withrespect to environmental management looked somewhat optimistic, but it is encouraging to note that they reported that more than half were developing environmental management systems. Training of varying degree was taking place at al levels in their organizations. Members saw their Institute as an important agent inlifting environmental awareness, literacy and responsibility not only through the journal and symposia, but also by liaison with government departments and educational institutions. Most respondents saw environmental legislation both from local and overseas sources as affecting their organizations, their products and services with the emphasis on corporate image, core business and sales.

Jan 1, 1995

By Hardwick F. W., O'Shea L. T.

The survey covers: coal-mine lighting prior to the invention of the safety-lamp, including candles, the flint-and-steel Spedding mill, and mirrors; the growth in knowledge of firedamp; the Society in Sunderland for Preventing Accidents in Coal Mines; Dr. Clanny's blast lamps and steam lamps; George Stephenson's tube-and-slider lamp, triple-tube lamp, punched-plate lamp and gauze Stephenson lamp; Sir Humphrey Davy's lamps; the controversy over invention priority, and other early forms of safety-lamp; 1816-1835 developments including the lamps of Upton and Roberts, M.Mueseler, John Martin, Dr. Clanny (new 4th lamp), M. Agre, John Newman, Gossart and Roberts, Francis Ellis, John Dillon and Mr. Wood (refrigerating lamp); 1836-1843 developments, notably of Mueseler lamps; 1844-1866, including lamps of the Davy, Clanny, Boty, Eloin and other types; 1867-1879, including the Gray lamp; 1880-1887, including the Marsaut lamp; and 1888-1913. Detailed reference is made to the findings of various relevant Royal Commissions and appendices include a list of the safety-lamps described in an appendix to the 1886 report and a publications list. The paper was prepared for the International congress of mining, metallurgy, applied mechanics and economic geology to have been held in London in July 1915. Discussion (p.718-724) includes a brief comment by Blackett W.C. and a longer contribution by Ashworth J., with the authors' response

Dec 1, 1916

By W. McMahon

Following the Sago Mine accident, the Mine Safety and Health Administration (MSHA) asked the U.S. Army Engineer Research and Development Center to study several possible methane explosion scenarios in the Sago coal mine. The study used a 1-ft resolution map of the mine to produce a 3-dimensional (3-D) model of a portion of the mine, including the sealed area where the explosion occurred. An advanced 3-D computational fluid dynamics (CFD) code was used to calculate the explosion pressures within the sealed area, on the mine seals, and in nearby regions of the mine. Based on the best available information on methane concentrations and assumptions on homogeneity and on layering and mix composition, three separate initial conditions of methane-air concentrations and location were studied. This paper discusses the CFD modeling technique, the results of the calculations, the challenges of conducting this type of modeling, and the advantages and limitations of CFD modeling of accident investigations of mine explosions.

Jan 1, 2009

By J. W. Thompson, M. N. RICH

That there is wide interest in the preparation and properties of metallic zirconium and its salts is indicated by the many articles recently published in scientific and technical journals and the many patents issued. The compounds of zirconium have numerous important uses and more uses will doubtless be found. In the course of the special work on rare metals that were of military importance during the war, the authors of this bulletin were detailed to the Golden mining experiment station of the Bureau of Mines to prepare metallic zirconium and to investigate its properties. A number of investigations in recent years have indicated that sintered or coherent zirconium metal is very resistive to acids; that it can be used for electrodes, and it probably will find metallurgical uses. A steel containing zirconium has been proposed for use in armor plate and automobile parts, and nickel-zirconium alloys have been suggested for high-speed cutting tools and for cutlery. Numerous articles in scientific journals have recommended the use of zirconium oxide as a refractory, an abrasive, a pigment in paints, and as an opaquing agent in enamel ware. The salts have been used in the textile industry' as a mordant and also for weighting silk. When the authors began their investigation, they found it necessary to collect all of the available literature on the general subject of zirconium and its compounds. Pure salts could not be obtained on the market, and in order to get these, as a preliminary step to the preparation of the metal, the literature had to be classified and the methods of preparing the salts investigated. Also, there was much difficulty at first in making satisfactory analyses, and this phase of the work received careful attention. As it was necessary to begin with a historical review of the literature, such a review is given as Part I of this report, and a bibliography is included as Part IV. References to the numbered items in this bibliography are made throughout the text, the usual footnote references being omitted. Analyses of the products and conclusions as to their purity are given under the descriptions of methods of preparation. A table showing the properties of the amorphous metal, and another showing the properties of the coherent metal, will be found under appropriate headings in Part II. No attempt has been made in the historical review to discuss fully all the published information about zirconium and its compounds, but only such material has been assembled as has a direct bearing upon the present work. Considerable difficulty was experienced in collecting this material because of the confusion of terms by various authors who perhaps did not thoroughly understand the chemistry of zirconium.

Jan 1, 1921

By Jack Thibodeau

During the past six years, most states have promulgated water quality regulations which contain numerical aquatic life standards for heavy metals. In addition, the Environmental Protection Agency (EPA) promulgated national water quality standards in 1992 which also include numerical aquatic life criteria for heavy metals. Numerous wastewater discharge permits have been issued by the states and EPA to industrial facilities which include low microgram per liter heavy metal limitations. In many instances, the limitations are below detection limits or treatability limits using state-of-the-art analytical methods or treatment technologies. This paper will discuss options for conducting studies, including the use of water-effect ratios, metal partitioning coefficients, and recalculation procedures to develop site-specific metals criteria and higher permit limitations. The installation of expensive metal treatment systems to remove trace metals may be avoided if higher permit limits are indicated by the site-specific studies.

Jan 1, 1996

By D. Spitty

Mining companies often have many disparate systems and repositories of data in their organization for planning and scheduling outbound mining supply chains. To optimize ore quality, throughput, transport logistics scheduling and delivery to contract, planning teams need to model and manage the value chain accurately and achieve a consolidated, enterprise view of operational performance. Planning teams coordinate a complex series of activities to ensure production forecast accuracy. They also negotiate and execute complex contracts often with disconnected and limited visibility of production forecasts, quality, and variability with little ability to accurately market potential product specifications over longer time horizons. This market is becoming increasingly dynamic, with increasing variability and the time for planning teams to react is decreasing. This is driving the need towards using science to generate the necessary scenarios required to support the decisions made by planners on a frequent basis. Resource-to-Market is a highly flexible, user-configurable supply chain management system for the mining and metal processing industries. This provides an integrated view of the supply chain that supports the dynamic nature of planning in a mining company, embraces variability of elements across the supply chain with the ability to optimize across all the functional areas of the operation to enable optimal decision making for often competing objectives such as throughput, quality, cost, revenue and profit.

Feb 23, 2014

By O. C. Ralston

The Bureau of Mines has under development on a technical scale an electrolytic process for treating oxidized ores of zinc , using caustic soda as an electrolyte . Whereas the Bureau process can alternately make either solid zinc or zinc dust , the following paper , from the Ludwigshafen research laboratory of the well -known I. G. Farbenindustrie , A. G. , of Germany, deals only with production of zinc dust from sodium zincate solutions and may well serve as introduction to the subject for American metallurgists . The Bureau of Mines pioneered in the idea ; a study on laboratory scale by H. J. Morgan and 0. C. Ralston was made early in the First World War, and published in Transactions of the American Electrochemical Society . The Eckardt paper , translation of which follows , goes more thoroughly into the preparation of electrolytic zinc dust , and later publications of the Bureau of Mines will deal with broader details and application of the idea to treatment of lowgrade ores and metallurgical intermediates , which is the point where Eckardt left off . 4 The Eckardt report became available through operations of Field Information Agency , Technical ( FIAT ) of the Office of Military Government for Germany (US ) , which made bibliofilm copies of the files of internal technical reports of many of the German industrial establishments , Eckardt's report is dated April 1939 and was taken on FIAT Microfilm Reel MM 106 , frames 82-101 , which is on file as Publication Board Document 41411 in Office of Technical Services of the U. S. Department of Commerce , Washington , D, C , Eckardt points out that the normal source of zinc dust is the blue powder of the zinc retorts , which decreases in volume every year owing to technologic improvements in zinc smelting. I. G. saw the importance of making a

May 1, 1948

By Pavel A. Torres, Darwin Torres, Sandro Huaman

Given the limited efficiency of blast-induced ground vibrations prediction empirical models, due to the complex geological system from a Peruvian mine. An artificial neural network was built in order to get better results. More accurate and precise predictions allowed the generation of blasting domains for future designs and decision making.

Feb 1, 2020

By Boyd Eisenbraun, Dennis Murr, Milton Rojas

Approximately since 1925, the phenomena of grinding and classification of minerals with screens have been studied. In the U.S. iron ore mining operations located in the so-called “Mesabi Iron range,” magnetite processing plants have made progress in the application of high-frequency screens that have allowed them to process low-grade Taconite ores and successfully achieve the economic benefit of these minerals. In the particular case of magnetite minerals disseminated in the siliceous matrix, the main objective is to reduce the generation of particles called “middlings” with high silica contents. Commonly the primary challenge of the metallurgical task is to achieve high recoveries and iron concentrates with low impurities. To achieve this, several studies and industrial applications have shown success in this regard and not only in iron ores, but also in other minerals around the world. The study described in this paper attempts to describe some key aspects that helped develop an effective solution and list the benefits associated with this modern process design by using industry-proven technologies for minerals in Chile that have similar characteristics to the minerals of the iron belt in the United States.

Feb 1, 2025

By J. J. Foster

MOST of us will, I think, agree that never before in the history of the coal industry has the human side of our business been so important as today. Since, even in wholly mechanized mining, labor cost is such a large percentage of out total cost we are all deeply concerned not only about the present attitude of our employees but particularly about the future, when the industry returns to a "survival of the fittest" basis. Many things could and should be done about our employee relations in the coal business. Failure to recognize these obligations and do something about them may lead to serious consequences, the least serious of which will be the loss not only of many of our better employees but a large portion of our potential employees, as they graduate from our schools to other in¬dustries. Some of these things should be handled by the industry as a whole whereas others should be done by individual companies. Due to varying conditions and size of organizations it would, at best, be necessary to vary a program to meet the individual needs of each operator.

Jan 1, 1945

By B McCarthy

Mining has been typified of late as a boom and bust, cyclical industry operating against a steady decline in the size and quality of mineral deposits. Decreasing deposit grades and increasing costs of traditional mining techniques, all in the face of another commodity downturn, are forcing mining companies more than ever before to seek out new and innovative ways to operate. New technologies are emerging to model, control and track resources through the mining value chain, to move material about mines more efficiently, and to identify and separate ore from gangue early in the extraction process.Discovering such technologies however is only the first challenge for mining companies. Actually implementing technological change successfully has proved to be an even bigger challenge. Like for many industries, fulfilling the promised benefits for the expense and timing envisioned, has not been easy when innovative technologies are introduced.Citing the author’s insights and experiences in a number of emerging technologies, this paper explores barriers to implementing technological change in the mining context. Key elements of a change management framework, first developed for implementing mine management systems, are described to give mining executives insight into how they and their organisations can succeed through technology-driven change.CITATION:McCarthy, B, 2016. Successfully implementing technology-driven change in the mining environment, in Proceedings International Mine Management Conference, pp 89-104 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

By A Parbhakar-Fox, S C. Dominy

The prediction of acid and metalliferous drainage (AMD) from mine waste materials is critically important during all stages of the mine value chain. However, to determine such geoenvironmental characteristics static and kinetic testing of individual waste units must be performed on representative samples. The importance of sample selection cannot be underestimated; it is the single most critical aspect of any geoenvironmental investigation. Poor sampling techniques and inadequate sample selection will contribute to excessive variance, difficulties in interpretation and incorrect assessment. By undertaking mesotextural characterisation based on hyperspectral mineralogical data (with sulfur assay data if available), opportunities to improve sampling strategies are presented. Such data will inform the selection of samples for low-cost total sulfur, paste pH and geoenvironmental logging, which collectively will allow for accurate AMD forecasting and improved sampling practices to be achieved. Once sampled, robust quality assurance/quality control (QA/QC) protocols must be developed where the use of international certified reference standards become obligatory. This is currently not practised, resulting in inter-laboratory discrepancies when undertaking waste classification. Further improvements in geoenvironmental characterisation testing lies in the adoption of blended static testing protocols, whereby blends of waste materials can be efficiently tested so as to give an early forecast as to whether they will produce acidic or metal-laden drainage. Such information is integral in developing a waste schedule that will allow for a non-acid forming waste landform to be constructed right from the start of the operational phase. Ultimately, improvements in this discipline lie in technological innovations with regards to mineralogical characterisation, and by offering geoscience and minerals engineering students a competent education in the discipline. Collectively, this will empower a step-change in AMD prediction and waste handling, and will make the realisation of the United Nations Sustainable Development Goals a reality, rather than a dream.CITATION:Parbhakar-Fox, A and Dominy, S C, 2017. Sampling and blending in geoenvironmental campaigns – current practice and future opportunities, in Proceedings Eighth World Conference on Sampling and Blending , pp 45–54 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By M Castello, P Bouchard, M Sabsabi, A Blouin, B Nguegang Kamwa, M Constantin, K Fytas, M Laflamme, K Rifai, F Vidal

Canada’s Quebec province operates 26 metal mines, 19 of which are producing gold and generating over C$1.8 billion (US$1.3 billion) annually. In all those mines, numerous samples of rock are collected and analysed daily in laboratories in order to determine their gold content. However, laboratory results are generally available within 48 hours of sampling (depending on the number of samples received by the laboratory and the priority of the results), thus potentially slowing down mining activities. In an attempt to find a solution for delayed laboratory results, Laval University, in partnership with the National Research Council Canada (NRC), the National Institute for Scientific Research (INRS) and four mining companies (Agnico Eagle, Canadian Malartic, Hecla Québec and Iamgold) have launched the Laser-Induced Breakdown Spectroscopy (LIBS) project for in situ real-time mining sample analysis. This work aims to minimise the amount of LIBS point sampling necessary to be representative of a full scan of the analysed area. Eight sampling patterns are investigated. A statistical analysis of the data was performed by varying the pattern steps. Results show that two of the patterns, 1 and 5 (single diagonal crossing the stratification of the samples with opposite slopes) minimise the amount of point sampling while remaining representative. The most successful results are obtained from steps which are greater than 6. In terms of the type of material, pattern 5 and steps 9 are better for core sampling, while pattern 1 and steps 8 are better for rock sampling. The geological explanation for these results is the heterogeneous distribution of gold in the sample which seems to be more homogeneous in the rocks than in the core sample due to the small rock size. In terms of the mineralisation, pattern 5 is better for mixed sulfides and quartz veins, and steps 8 and 9 are better for quartz veins.CITATION:Nguegang Kamwa, B, Rifai, K, Laflamme, M, Constantin, M, Castello, M, Vidal, F, Bouchard, P, Fytas, K, Blouin, A and Sabsabi, M, 2017. Sampling strategy by statistical analyses of LIBS data in the context of a portable gold analyser, in Proceedings Tenth International Mining Geology Conference 2017, pp 221–232 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By A. A. Brant

ONE of the reasons advanced for the decline in prospecting and discovery is that, as regards surficial examination, the law of diminishing returns is becoming applicable. Fewer surficially unprospected fields remain; therefore, fewer discoveries by such means result. Much in the nature of mineral resources remains to be unearthed, but even now, and more so in the future, will discovery depend on painstaking petrographic and structural mapping, aided, where necessary, by judicious applications of all the complementary scientific knowledge and devices (e.g., thin section microscopy, geophysics, and drilling) that experience proves effective in localizing a mineral deposit even beneath drift, lake, or muskeg. It is to be expected, then, that the rate of discovery will decrease, that the cost per discovery will greatly increase, and that the work of discovery will become more and more the careful, methodical assembling of field data, conscientiously interpreted on the basis of scientific knowledge by trained, experienced operatives. In view of these trends, the status of applied geophysics to Canadian mining exploration and development work might well be reviewed. The niche which geophysics may occupy relative to geological surveying and drilling has been clarified by the last twenty years' experience. The cloud of somewhat justifiable scepticism that followed the 'geophysical promotion' period of the late 1920's has lifted. Mining, exploration, and finance companies, in open-minded fashion, are seeking sound advice as to what are the scope and limitations of the geophysical methods at present practised. The purpose of this paper and the following one is, therefore, as far as lies within the author's power, to review briefly the geophysical methods at present in practice in Canada, and, at greater length, to joint out impartially and critically their scope, merits, shortcomings, an possible future development. The treatment will be non-technical, the hope being that an accurate statement of the present status of geophysics in Canada may do much to result in a sounder, saner growth of what, in the future, shall undoubted} y prove an increasingly useful tool in exploration and development work. ?

Jan 1, 1942

By J. R. Evans

Mining claims must have a discovery of a valuable mineral deposit to be valid. When required, a Federal government mineral examiner makes a determination of validity and recommendations thereof to authorized management officials. The examiner should show whether or not an existing mining operation, or a proposed operation have economic viability. This is accomplished through an analysis of legal entities, land status and use, geologic and mineralogic relationships, and mining, milling and processing techniques considered in an appropriate economic evaluation framework. A framework involves market and market entry studies, reserve analyses, all costs analysis, royalty buyouts, tax structure, discount rate of return, and escalation and risk factors. An income approach to value is then used by means of a simple or complex discounted cash flow (DCF) analysis to certify validity. Whether one claim is owned by a single miner, or hundreds of claims are owned by a large corporation, thorough, fair, consistent, and appropriate economic concepts should be applied by the mineral examiner.

Jan 1, 1993