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By D. Preece

The mining and oil industry employs techniques such as geologic mapping, core drilling and electromagnetic and potential field techniques to explore for new deposits. Since new discoveries of major near-surface ore bodies are becoming progressively rare and since traditional exploration methods are unable to resolve ore bodies deeper than about 500m, high-resolution seismic reflection techniques show great potential for exploration to much greater depths down to almost 3km.

Jan 1, 2011

By Pascal Lesagel

Life Cycle Assessment (LCA) is a holistic environmental assessment tool that allows the compilation and evaluation of the inputs, outputs, and potential environmental impacts of a product or service throughout its life cycle, from cradle to grave (i.e., from resource extraction and transformation to final disposal, including production and use stages). The relevance of LCA for the mining industry is twofold. First, the mining industry has a role in providing the LCA community the data that allows subsequent evaluations of the life cycle environmental impacts of primary materials such as metals, as well as the environmental comparison of the downstream products of the mining industry with other competing materials for specific uses. Second, the mining industry can use LCA in order to evaluate the environmental impacts of its activities, identify their environmental hotspots and compare the impacts of available technical options. For example, the environmental impacts of different extractive and processing technology can be compared through the use of LCA. This latter use of LCA by the mining industry is less common. This paper discusses the use of LCA to compare sulphidic tailings management options. The paper also presents some of the LCA research challenges that still have to be addressed to increase the relevance of LCA results for the specific context of mining activities.

Nov 1, 2008

By Amy Anderson

The Silica (SME) Technology has been utilized on three separate projects focusing upon the stabilization of mercury-contaminated materials: at the Mother Lode Mine in Oregon, the Sulfur Bank Mercury Mine in California and at a former chloralkali plant in British Columbia. Each of the projects relied primarily on the results collected via EPA Method 1311 TCLP, with additional tests such as SPLP, humidity cell tests and other supporting tests employed as well. Both technical and economic performance of the silica-based technology was evaluated as well as that of competing technologies in some cases. Results established that in each of the three projects an SME chemical dosage rate of 3% chemical by weight of soil/sludge was the optimal ratio required to achieve project treatment objectives, TCLP test results exhibited a reduction in the leachable mercury from the treated materials ranging between 75% and 99% as compared to untreated material, satisfying the technical objectives for each project, Project costs ranged from $l5.00 - $18.26 per metric ton.

Jan 1, 2003

By Andrew Allan

During recent years underground production for the Pennsylvania anthracite region has reached the lowest output per man per day figure of the last decade and a half. This fact, combined with increased unit costs for labor and material, has forced the market price of anthracite ever higher. Over the years the mines have become deeper, and haulage distances have increased, thus adding to the mining costs. The industry now recognizes the need for new mining techniques to offset increasing costs. The Federal Bureau of Mines, through its Anthracite Research Laboratory, is engaged in a program of underground-mining research in cooperation with anthracite-producing companies to aid in reestablishing the economy of the region by introducing methods and/ or machines that will reduce underground-mining costs and, at the same time, enhance the safety of the workmen.

Jan 1, 1953

By R. D. Brown

In his March 31, 1977 budget, Finance Minister Macdonald has attempted the delicate balancing act of stimulating the economy without reinforcing the inflationary pressures which Canada is continuing to experience. Several tax changes of benefit to the mining industry, as well as measures designed to encourage oil exploration in frontier areas, are among the budget proposals. Additional earned depletion of 66- 2 /3 %, which may be offset against income from any source, will be available on drilling costs in excess of $5 million incurred between March 31, 1977 and April 1, 1980 in connection with an exploratory well in Canada, including the continental shelf . Other changes include more favourable treatment of resource property dispositions, less restrictive rules r elating to "successor corporations" , increased capital-cost allowance on railway spur lines, the inclusion of certain production royalties in Canadian development expenses and the application of the lower "manufacturing and processing" tax rate to sulphur production. To encourage business capital spending, the 5% federal investment tax credit it to be extended an additional three years to mid 1980 and broadened to include spending on scientific research and development. The rate of credit will also be selectively increased on a regional basis, to 7.5 % in certain designated areas in Saskatchewan, Manitoba. Northern. Ontario and Quebec, and to 10% in the Atlantic provinces and the Gaspe.

Jan 1, 1977

By Montaser S. El‑Salmawy, AHMED A. S. SEIFELNASSR, Ahmed Al‑Abady, Abdeaziem M. Abdelaal, Amr F. M. Ibrahim

Iron is a key detrimental impurity in silica sands that determines their contribution to high-technology industries. Herein, a simple ecologically sound approach is investigated for iron removal from a silica sand sample obtained from the El-Zaafarana area-Egypt. The sample was subjected to a detailed microscopic mineralogical study supported by XRD and XRF characterization. The sample was beneficiated using distilled water attrition scrubbing and screening over a 25 μm sieve followed by leaching using a mixture of equal amounts of phosphoric and oxalic acids. Leaching experiments were designed and analyzed using the Box-Behnken design (BBD) methodology. A model was developed and evaluated using the analysis of variance technique to map the relationship between the residual iron oxide in the produced concentrate and selected variables such as leaching temperature, oxalic acid, and phosphoric acid concentrations. XRD and mineralogical analysis reveal that quartz is the most dominant constituent of the studied sand and other minerals such as kaolinite, iron oxide, rutile, and zircon exist in trace amounts. The head sample shows a silica and iron oxide content of 95.69% and 2379 ppm, respectively. Attrition and separation over a 25 μm sieve increase the silica content to 97.05% and decreases the residual iron oxide to 455 ppm. The final product after leaching under optimized conditions shows 99.82% silica and 55 ppm iron oxide.

Aug 30, 2022

By R. M. Taylor

Lime addition to acid mine drainage (AMD) leads to precipitation, predominantly of metal hydroxides and calcium sulfate, and is the benchmark for remediation by precipitation. Geo2 Limited of Melbourne, Australia has developed and patented a novel alternative precipitation scheme based on the formation of mixed valency, M(I1)-M(III), hydroxide sulfate salts. When the composition of AMD is appropriate, the Green Precipitate Process provides a useful and more effective alternative to conventional liming. The characteristics and utility of the Green Precipitate Process are described in terms of the underlying chemistry, and a case study where the Green Precipitate process outperforms conventional liming. A mobile pilot pipe reactor rig which was built by Geo2 to demonstrate the process, and used successfully in both Australia and the United States, is described.

Jan 1, 1998

By D. D. Lei, H. Sevim

Long-term production planning in open-pit mines requires the determination of cut-off grade, mining and milling production rates, a mining sequence, mine life and ultimate pit limits. Since these variables interact in a circular fashion, a genuine solution to the problem necessitates their simultaneous determination. A methodology with this capability is described. This comprises a group of heuristic algorithms and an unconventional dynamic programming algorithm. The method is demonstrated using data for a gold deposit in the western USA

Jul 1, 1996

By N. A. Jabit

The dissolution behaviour of ilmenite in acid solutions has been studied by many researchers to improve the leaching efficiency. Most studies which utilized natural ilmenite from different origins resulted in different reactivity due to the alteration caused by the weathering process. Previous researchers have suggested that the greater reactivity shown by some ilmenite samples towards sulphuric acid may be a result of the mineral being relatively unaltered. In the present study a rotating synthetic ilmenite disc of 2.2 cm diameter was subjected to leaching studies in hydrochloric acid. The dissolution rates of iron and titanium from synthetic ilmenite were determined in hydrochloric acid solutions (4 M to 9 M) over a temperature range of 50 to 80°C. Results show that the rate of dissolution of both iron and titanium increased with the increase in acid concentration. However, the rates decreased with time and obeyed a parabolic rate law indicating the blockage of the surface by an insoluble product. The rates of dissolution of both iron and titanium were higher in the presence of SnCl2 and remained unaffected with time indicating the reductive role of SnCl2 which inhibits the formation of surface blocking solids. Application to natural ilmenite is also discussed.

Jan 1, 2014

By H Lieberwirth, M Pfeifer, F Heinicke

HPGRs (high pressure grinding rolls) have been developed within the last decades for energy efficient processing of a wide variety of ores. Special interest has been raised by projects increasing the capacities of processing plants by installing HPGRs prior to ball mills. Bond ball mill tests have been used for decades as a base for ball mill dimensioning in mineral circuits. For final CAPEXOPEX considerations of the processing circuit, one key question is about the level of grinding energy split between HPGR and downstream grinding stages. This is especially interesting if the downstream process comprises multiple grinding stages combined with separation steps. The paper presents investigations on grinding energy consumption, size distribution and microfracturing of HPGR products, which affect the efficiency of the whole comminution and sorting process.

Aug 24, 2022

By P. C. Benedict

"The Island Mountain mine is at the southeast end of Island mountain; across Jack of Clubs lake from the Cariboo Gold Quartz mine.; The orebodies consist of quartz veins and pyritic replacement deposits in limestone. To December 31; 1944; there has been mined 296; 273 tons of quartz-vein ore averaging about 0.34 oz. gold a ton; and 101; 002 tons of sulphide ore averaging about 0.83 oz. gold a ton; a total of 397; 275 tons averaging 0.46 oz. From this; 175; 985 fine oz. of gold and about 26; 450 fine oz. of silver were recovered; having a value of $6; 510; 521.More than 95 per cent of the production has come from a band 500 feet wide along the contact of the Rainbow and overlying Baker members and extending about 100 feet into the latter. Evidence that the Rainbow belongs stratigraphically above the Baker is presented later in this paper. Both members are most variable lithologically, and individual beds and whole series of beds pinch out in short distances. In part, at least, this is due to squeezing out incidentally to intense folding. No section can be claimed with assurance to be really representative. However, both memb.ers are composed predominantly of quartzitic rocks. Both contain argillaceous quartzite, argillite, limy quartzite, limy argillite, limestone (marble), and minor amounts of highly ankeritized rocks believed to be igneous sills possibly originally approaching diorite in composition."

Jan 1, 1954

By Valois R. Shea-Albin

An accurate assessment of the vertical stress on a coal seam at depth is important for mine design. Vertical stress calculation techniques presently available either are not sufficiently accurate or cannot handle complex surface topography. Therefore, the U.S. Bureau of Mines developed a computerized method to calculate vertical stress exerted on surfaces at depth that includes the effect of topography. Two input data sets are required: a digital elevation model containing topographic elevations and a coal seam file defining coal seam elevations at depth. Boussinesq's equation then quantifies the vertical stress resulting from topography. The computerized method was tested on a coal seam overlain by a complex topography where a vertical stress map encompassing several square miles was produced. Results show that depth mitigates the affects of surface topography, while the coal seam topography has a direct effect on the vertical stress. In comparison to the computerized method, the direct stress method overestimates stress under hills and underestimates stress under valleys. The largest difference between the two methods occurs under the steepest topographic relief. A limitation of the computerized method is that stresses cannot be accurately determined near an outcrop.

Jan 1, 2010

By H. Kosmider, P. Coheur

New processes of blowing with an oxygen-enriched air or gas mixtures of oxygen and steam allow the steelmaker to produce, in a basic converter, a rimmed steel low in nitrogen (0.0020 pct), phosphorous (0.020 pct), and sulphur (0.020 pct). The physical properties (ductility) of the new steels are excellent. Furthermore, from the point of view of economy, these new methods of blowing offer outstanding possibilities. THE natural occurrence of geological deposits of iron ore and local economic circumstances led European blast furnace men to work large quantities of lean iron ore with a phosphorus content as high as 0.5 pct. The iron obtained from these ores generally contains 1.5 to 2.1 pct phosphorus, 3.6 to 3.9 pct carbon, 0.3 to 0.6 pct silicon, 0.04 to 0.08 pct sulphur, and 0.3 to 1.2 pct manganese. To produce steel from this pig iron, the steelmaker has at his disposal several processes. One of the simplest and most economical is the pneumatic process developed by S. G. Thomas in 1879. This process of steelmaking, called the Thomas process, consists of blowing through the bottom of a basic bessemer converter and is used widely in Western Europe, as shown in Table I. Due to the development of tonnage oxygen plants, this process has become more important because the use of oxygen offers new possibilities of steel manufacture. Not only may the quality of the steel be improved, but liquid pig iron also may be used, the composition of which does not meet the heat requirements of the blow with atmospheric air. It is not intended to present here a detailed scientific discussion of the basic bessemer process but rather to discuss briefly its industrial possibilities in the case of rimmed steel and when blowing with atmospheric air, oxygen-enriched air, or gas mixtures of oxygen and steam. This paper is based on the current practice at Klockner-Hüttenwerk Haspe's steel division, and at six Belgian and Luxemburg steel works. The latter are members of the Liege section of the C.N.R.M. (National Institute for Metallurgical Research) and are: ARBED, John Cocker-ill, Esperance-Longdoz, HADIR, Miniere et Metal-lurgique de Rodange, and Ougree-Marihaye, most of which are working with tonnage oxygen plants.' In order to avoid any misunderstanding, it should be noted that most of the techniques to be men- tioned, or similar ones, are used currently at many steel plants in Western Europe. Background The basic converters used in Europe have a capacity of 17 to 65 tons of steel, and are similar in shape to the one in Fig. 1. The lining is brick or rammed dolomite and has a life of 250 to 500 blows. The bottom is rammed dolomite and has a life of 40 to 80 blows. As far as we know, the type of blast used does not appear to have any influence on the life of the lining. Bottom life, on the contrary, depends very much upon the composition of the blast. It is only when

Jan 1, 1955

Commercial explosives range from pure emulsions to pure ANFO, with blends of these providing interesting alternatives: energy is often adjusted through addition of aluminium, or the control of density. The energy rating of explosives is derived chiefly from detonation codes, which are used to derive expressions for the internal energy change of the detonation products as they do work under expansion. While all codes used for this purpose work on the basis of Ideal detonation, it is common knowledge that commercial explosives operate in the Non-Ideal domain, which affects the mode of energy delivery to the environment. However, since Ideality represents the foundation from which actual performance evolves, it is valuable to examine the intrinsic energy release of a formulation before attempting to understand the influence of Non-Ideality. In examining the Ideal pressure profile of fundamental formulations, remarkable correlation has been found with field performance, and this increases understanding of the influence of various formulation modifications, especially in regard to the stage at which energy is released, and the effect on rockbreaking. This work has emphasised the value of attempting to understand and define better the non-ideal detonation process.

Jan 1, 2001

By Sean Hillacre, Arthur Lieu

NexGen’s approach to uranium processing design including the crushing/grinding and leaching of raw ore through to yellowcake precipitation and tailings management focuses on minimizing surface footprint, freshwater consumption, and human radiation exposure. Applying the concept of best available technologies economically achievable (“BATEA”), NexGen continues to research, evaluate, test and validate various advanced technologies that can be incorporated into the Project design, including distinctive tailings storage techniques. Additionally, NexGen is proposing that tailings generated from the mill processes be used as cemented paste backfill of stopes, as well as stored in a purpose-built, Underground Tailings Management Facility (“UGTMF”) comprised of several dedicated chambers. The paste backfill method of tailings storage is used globally, however, constructing purpose-built tailings chambers in waste rock is a new concept in uranium mining, which would typically be cost prohibitive for most projects given the expense to develop non-economic material for the sole purpose of storing tailings. The Rook I Project is uniquely positioned to implement the UGTMF due to robust Project economics and favourable technical setting which provides NexGen with the opportunity to set an elite standard for tailings management. When compared to conventional surface tailings management facilities, storing tailings underground as cemented paste reduces geotechnical, geochemical, environmental, and human health risks associated with tailings management. Additionally, the UGTMF vastly reduces the area of surface disturbance and allows for progressive decommissioning during the life of mine operations.

Jan 1, 2020

By R. C. Rowe

THIS paper is an endeavour to analyse the ideal and practical functions of government technical mining services, and their relationship to the National Domain, as well as to one another. its spirit is not critical, even though at times it may appear to besoin fact. It is a serious effort to divert a trend in public thought which delights in calling itself practical whereas it is really merely short-sighted. The author refers particularly to the idea that governmental research is a luxury which should be curtailed in the interests of economy, and turned over to private enterprise or the provinces. In order that we obtain the proper perspective of the question, it is advisable to indulge in a little history. In the year 1842, the Geological Survey of Canada was formed under the guidance of William (later Sir William) Edmund Logan. The literature on the founding and history of the Geological Survey of Canada is extensive, and therefore it is unnecessary to go into detail here regarding it. It might be mentioned, however, that the Geological Survey of Canada is only seven years younger than the Geological Survey of Great Britain (founded in 1835), and is only exceeded in age on the American continent by the State Geological Surveys of New York, Pennsylvania, Massachusetts, and Michigan, which were founded between 1833 and 1836. In 1877, the Geological Survey became a permanent government institution as a branch of the Department of the Interior. It should be noted, however, that the Director of the Survey ranked as a Deputy Minister and reported direct to the Minister. This continued until 1907. In 1886, the Mineral Resources and Statistics Division of the Geological Survey was formed. Some years later, the Canadian Institute of Mining and Metallurgy (then the Canadian Mining Institute), backed by the mining press, began to agitate for the establishment of a Dominion Department of Mines, and in 1907 such a department was founded by the Geology and Mines Act of that year, with a separate Cabinet portfolio for the position of Minister of Mines.

Jan 1, 1939

In this paper, three types of value-adding in the minerals industry are discussed: downstream processing, improving the efficiency of existing processing and increasing the knowledge base and expertise of the staff. It is shown that, while downstream processing seems to offer a good way of improving Australia's trade position, there are a number of impediments to such development, notably, limited access to the appropriate technology and overseas markets. Transport costs can also be a problem. To reverse the situation will require more positive policies by government. In the meantime, something can be done towards adding value by increasing the efficiency of existing processes. Examples are given, showing how it might be possible to make economies in reagent costs in the gold industry, how innovative technology has led to more complete processing of a tailings dump, how research might lead to an increase in the throughput in the production of synthetic rutile and how it is possible to leach selectively from gold/copper ores.

Jan 1, 1995

By S. J. Aresco

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analyses. To these, when required, are added the ash-softening temperature, the free-swelling index, and the Hardgrove grindability index. Under most of these specification contracts the bidders guarantee the quality of the coal, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled in accordance with instructions4/ issued by the Bureau of Mines, the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor and, if it is not, a price adjustment is made. Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous sampling of coal as delivered is a check on the practical results obtained in burning the coal.

Jan 1, 1957

By M. E. Volin

The tungsten potentialities of the Combination mine were examined by a mining engineer of the Bureau of Mines in 1947. A report based upon his personal knowledge of the mine and the results of the examination contained recommendations for further investigation. This report presents factual data from Bureau of Mines field investigations begun in August 1947 and continued until December 1948, except for a 5-month recess during the first winter. The Combinat.ion mining property of 52 patented claims and 15 patented mill sites is in the Black Pine mining district, Granite County, Mont., 11 miles northwest of Philipsburg. The altitude in the mine vicinity is approximately 6,500 feet.

Jan 1, 1952

By Derek J. Fray

Electric arc furnace dusts, especially those containing zinc ferrite, are notoriously difficult to process to give valuable products and non-toxic residues. The ideal process would remove and recover the toxic non-ferrous metals as pure metals, of commercial value, and non-toxic residue which can be used as a raw material in the steel industry. From an examination of the thermodynamics of the oxides and chlorides of the various elements in the dust, it is apparent that the chlorides of the toxic non-ferrous elements are more stable than the oxides while the reverse applies to the ferrous elements. This offers the opportunity for a complete separation of the zinc, lead and cadmium from the iron oxide. Results are presented for the chlorination of electric arc furnace dusts under oxidising conditions and the subsequent treatment of the chlorides to recover the pure metals and chlorine which can be recycled back to the reactor.

Jan 1, 1994