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By J. W. Adams

This report surveys the efforts of six contractors to the U.S. Bureau of Mines with regard to their electromagnetic noise measurement programs. What has been done, what is planned, and evaluations and recommendations are given for each contractor. The main observation is that to date there is not sufficient knowledge of electromagnetic interference in mine environments to design a reliable communication system. This knowledge should be available by the end of June 1972 if certain planned programs are completed successfully. A major effort of this report is to establish parameters to be measured, units to be used, and workable formats for data presentation. This is given in Appendix A. Some details concerning equipment, procedures, locations, and sample data are included in Appendix B.

Jan 1, 1971

By W. Roggenthen, Z. J. Hladysz, G. D. Callahan, W. G. Pariseau, W. Weinig, C. Randolph-Loar, R. Popielak

A Deep Underground Science and Engineering Laboratory (DUSEL) is being planned at the site of the former Homestake Gold Mine in Lead, SD, under the sponsorship of the U.S. National Science Foundation (NSF) in cooperation with the Department of Energy (DOE). This national facility will host a variety of multidisciplinary science and engineering experiments, including physics experiments that require shielding from cosmogenic radiation. Current plans include construction of large rooms (up to 55 m in width) at depths of 1.48 km (4,850 ft) and 2.25 km (7,400 ft) below the surface. Preparation of the preliminary design required the development of a geotechnical characterization program, including preliminary drilling and coring, core logging, drill hole mapping with a televiewer, drift mapping of the geology and rock structure, in situ stress measurements, and laboratory testing of the mechanical properties of the rocks and discontinuities. Overall rock quality is very good to excellent. Site investigations included geotechnical assessments for the construction of caverns and laboratory modules. The results are favorable and reaffirm selection of the Homestake site for establishment of a Deep Underground Engineering and Science Laboratory.

Jan 1, 2011

The present study is devoted to improvement of the leaching efficiency during phosphorous removal from high phosphorous gravity-magnetic concentrate. Before leaching the concentrate has been subjected to roasting with the addition of either Ca(OH)2 or CaO. The oolitic iron ore is roasted at 900°C for one hour. This reflects in reaction between alkaline earth additive and quartz, aluminosilicates, phosphorus, and some other minor components of the gangue minerals. The application of leaching, physical separation, and wash out of salts has resulted in the decrease of phosphorus from 0.7 to 0.15 % and it is established that the major influencing factor is the concentration of acid and to a less extent duration of the leaching process. About two third of the phosphorus can be removed by roasting with 3 % CaO to hematite, coarse grinding to d50 0.3 mm, dry high intensity magnetic separation and leaching of the magnetic fraction with hydro-chloric or nitric acid.

Sep 1, 2012

By Edmund S. Leaver, Charles E. Van Barneveld

In response to numerous requests from metallurgists and operators for information regarding the status of the sulphur dioxide leaching process , developed at the Southwest experiment station of the U. S. Bureau of Mines , Tucson , Ariz . , the following statement has been prepared . A more complete report is now in course of publication and will appear as Technical Paper 312. This process was devised to provide a cheap and efficient method for treating the so- called "porphyry " copper ores of the Southwest which generally contain both " sulphide " and "nonsulphide " copper minerals , mixed in such proportions that they can only be satisfactorily treated by a method which will concurrently recover both the sulphide copper and the nonsulphide copper . The latter term has been adopted to include all the minerals commonly referred to in operating phraseology in the mills of the Southwest as " oxidized" , " oxide " , or " soluble " copper . confident that the sulphide dioxide leaching process , as developed by us with the cooperation of the Miami Copper Co. and the Arizona Copper Co. , is suitable and commercially available for a wide range of ores .

May 1, 1922

By D G. Randall, R Jivanji, J Nathoo, T Reddy

Paradoxically, the increased emphasis on water treatment in mining has generated a new problem û hypersaline brines. Currently brines are either disposed of into ash systems, lined evaporation ponds or hazardous waste sites. Evaporative crystallisation (EC) is an alternative, but the energy requirements can be prohibitive and the salt product is still a waste that must be disposed of. Eutectic freeze crystallisation (EFC) is an alternative technology that is capable of separating aqueous solutions into pure water (as ice) and pure, solidified solutes. It is highly energy efficient and does not depend on the introduction of any solvents. In addition, the simultaneous production of pure ice and potentially saleable pure salt(s) is a major advantage. Although EFC has been shown to be effective in separating a single salt and water, it is still in the early stages of being applied to the multi-component hypersaline brines that are typical of reverse osmosis retentates generated by mining and extractive metallurgy.This paper presents an EFC brine treatment protocol developed by the Crystallisation and Precipitation Unit at the University of Cape Town. The protocol incorporates brine analysis, thermodynamic modelling to establish which salts will freeze out and at which temperatures, followed by experimental studies to determine the kinetic parameters, such as nucleation temperatures, salt yields and crystal purity.Case studies showing the application of EFC for the purification of typical brines containing high levels of sodium, chlorine, sulfate and ammonia (Brine 1) and a mixture of sodium and magnesium sulfate (Brine 2) are covered. Modelling tools were applied to describe the phase behaviour of the multi-component saline systems under different process conditions. Experimental validation was carried out using synthetic brines of different (and increasingly complex) compositions. The results showed that EFC could be used to selectively recover the sodium as a sodium sulfate salt from both different brines. The simulation tools were useful in the analysis and understanding of the process.A preliminary economic analysis showed that the operating costs for EC were approximately nine times those for EFC, but the capital costs were much less- equipment for EC cost about half that of EFC. However, it is important to note that the capital cost calculations for EC are based on a technology that is already well established and with only relatively marginal future equipment cost savings expected. In contrast, EFC is a new technology, with significant future technology improvements expected.

Jan 1, 2009

By Thomas H. Sheldon

IN the zeal for opening up new ore-bodies, or for. extracting the ore from attractive bodies gal ready opened up, we very often lose sight of the fact, that, after all, the operation of a mine is a business proposition, pure and simple; and for the best working-results should be treated upon a strict business basis. Of course, in every mine of consequence a record is kept of expenditures and receipts, and such glittering generalities as "gross receipts," " net receipts," " mining expenses," .and " per cent. profit," can be told to the cent; but does this . record show economy of management, either as compared with the same record of other months, or as compared to the record of other mines of the' same class ? Moreover, if such a record shows that the cost of mining is high, does it in any way en¬able the manager to put his finger on the leakage? Does it necessarily follow that a mine which makes a profit of, say, 40 per cent on 25-dollar ore, is doing less economical mining than one which saves 60 per cent on 80-dollar ore ? Of course the figures in the latter case look the more attractive, but when it comes to a point of saving everything which can be saved, and of cutting down expenses to the lowest possible cost of operation, the former mine is doubtless on the most firm and economical financial basis. But as the relative merits of the system of mining in the two cases, nothing could be decided without a basis of detailed comparison ; if one system is more economical than the other, why is it so, and wherein does the advantage lie ? This can be shown only by keeping accurately the cost of each mining operation. And no matter how dissimilar two mines may be in character and operation, yet there are a few general heads common to all mining operations. In the first place, it is necessary to break the ore from the solid ground ;

Nov 1, 1905

By Michael Casson

With the mining industry changing rapidly due to mergers, acquisitions and fluctuating market pricing, today?s market for coal, minerals, ores and aggregates demands electrical apparatus that perform every time with maximum efficiency and with consideration for personnel safety. This is especially true in existing mining operations where every payload counts. Draglines are the workhorses of surface mining operations, and reliable and efficient operation is absolutely critical to success. However, the inherent disadvantages of using dc motors and motor-generator (MG) sets can significantly impact productivity and return on investment (ROI).

Jan 1, 2013

By F. Dingwu

The latest technology and novel equipments in kaolin processing industry in China are described in this paper. Some typical experimental results are presented, which include laboratory-, pilot-or commercial-scale tests. The characteristics of kaolin processing technology are summarized, and the developing trends are indicated.

Jan 1, 1995

By Patrick Cloutier

Presentation objectives ? Introduce discrete-event 3D computer simulation as a tool to design, improve and optimize construction projects: ? Describe a real typical construction project planning issue. ? Present an applied use of simulation to solve this issue. ? Detail benefits of using simulation versus traditional planning methods.

Aug 1, 2013

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 of ash, 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 instructions~ 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, 1956

By X Tian, J Forster, A Olmsted, E R. Bobicki, M Goldbaum, D Boucher, C A. Pickles

As the global demand for metal values expands, it becomes increasingly important to create more sustainable mining operations. Consequently, considerable research and technology development is required to produce processes which are both more energy efficient and have a minimal environmental impact. One potential technology is the utilisation of microwave pre-treatment to reduce the energy requirements in comminution. Microwaves can preferentially heat the valuable mineral phases in an ore and the resulting differential thermal expansion leads to the formation of microfractures along the grain boundaries. As a result of the preferential heating, ore competency is reduced, mineral liberation is enhanced, a coarser grind size can be employed, and plant throughput can be increased. Furthermore, microwave pre-treatment can be combined with advanced ore sorting, to decrease the quantity of gangue material processed downstream and hence reduce tailings production. Previous studies on the microwave treatment of ores over the last 30 years have mainly been limited to low power bench-scale studies and there is a paucity of information on pilot and/or commercial scale studies. In the present research, the microwave heating behaviours of over 40 ores have been studied at the bench-scale. These results were used to generate a database, from which a unique classification system was developed. This system was used to rank the amenability of any given ore for microwave pre-treatment. This knowledge can be employed to predict the performance of the ores in the high-power pilot scale tests and thus can be used as a pre-screening tool. The effects of high-power microwave pre-treatment on grindability and liberation were reported. Additionally, the ore sorting potential was evaluated using a combination of X-ray transmission (XRT) and microwave infrared (MW/IR).

Aug 24, 2022

By A A. Latscha, D O’Connor

Increasing orebody complexity, restrictions in ground access, and longer lead times for disturbance approvals, have generated the need for the Resource Development Team within Rio Tinto Iron Ore (RTIO), to explore optimised drill design techniques that deliver resource conversion value while maximising program outcomes. In response to this challenge, the Team initiated a case study to produce an AI assisted/designed drill program using a non-machine learning AI. The case study involved the assessment and implementation of an AI generated drill program at one of RTIO’s Pilbara iron ore deposits, located in the Hamersley Province of Western Australia. The Mineral Resource is currently classified as 100 per cent Inferred. Access constraints inherent to topography, and the presence of exclusions zones have prevented adequate drilling coverage, resulting in lower resource confidence and a poor definition of the orebody extents and geometry. The drill campaign, planned in Q1 2023, needs to consider access constraints, complex topology and the limitations related to additional ground clearance, while addressing the requirement of improving orebody knowledge. The drill plan had to address two objectives. The first and main aim of drilling was to upgrade the Resource Classification to allow for possible conversion to Ore Reserve. The input for this objective was a volumetric representation of the areas currently not meeting pre-defined quantitative Resource Classification upgrade criteria. The second objective was to better define the orebody extents and geometry. For the second objective, the input to the drilling optimiser was a volumetric representation (blocks) of the areas of high uncertainty in the mineralisation/waste boundary, which were defined using an indicator conditional simulation technique. The drilling optimiser output was a range of compliant drill plans. A set of KPIs based on economic and orebody knowledge criteria were used to assess the plans and to select the most optimal drill design to be drilled in 2023. The geology and management teams were able to make better informed, objective decisions using the trade-off between cost and orebody knowledge gained. As part of the assessment, the AI generated plans were compared to our current planning practises. The AI assisted plans, when gauged against the project KPIs, showed clear and measurable improvements in both meeting project objectives and in managing operational risk.

May 24, 2023

By B. H. Moore

Foundation and excavation problems associated with lock construction projects vary widely. Each lock requires a different foundation to respond to a unique geologic setting. The range of heights and founding materials are illustrated thru description of selected structures encountered in the United States. Examples range from 113-ft high John Day Lock on the Columbia River founded on basalt rock to the 17-ft high Lock No. 5 on the Arkansas River floated on a clay foundation. A description of the basic elements of design and construction is presented. Several case histories involving lock design and construction are assessed to aid in recognition of potential problem areas on forthcoming construction. In the past decade there have been many improvements in construction materials and techniques. The application of these new approaches to lock construction is discussed.

Jan 1, 2010

When the Organic Act of 1910 established the Bureau of Mines within the Department of the Interior, the Bureau's programs involved only health and safety research and education, and fuels testing. As the Federal Government's primary agency for research in minerals, the Bureau has expanded its scientific and technological investigations to mining, processing mineral substances, eliminating occupational health and safety hazards in the mineral industries, economic development, and resource conservation. Today, Bureau activities cover a broad spectrum of programs for meeting the diverse (and sometimes conflicting) needs of mineral industries, government, and the public. In the 1960's, the Bureau initiated programs to resolve environmental problems associated with past mining and mineral processing. Dependence on foreign sources of raw materials critical to our national economy and competition from other countries for these world supplies stimulated the need to conserve and use with intelligence the Nation's minerals, metals, and materials.

Jan 1, 1978

By Margaret Anne Stephenson

While the concepts of Aboriginal title share a similar jurisprudence in both Australia and Canada resource development regimes on Aboriginal title lands differ significantly. In Australia, the process is the right to negotiate with mining proponents. In Canada, the process is the duty to consult with government regarding mining projects. This paper compares and assesses the processes for ?consultation and negotiation? with Indigenous peoples when development actions (particularly in the context of mining resource development) impact Indigenous property rights and how agreement making can be progressed. This paper will question whether the resource development processes afford Indigenous people?s property rights full respect when mining developments on Indigenous lands are proposed.

Aug 1, 2013

By V. J. Southey

HOLLINGER mining operations have required development by 24 vertical shafts having a total length of 28,160 feet. Seventeen of these are sunk from surface and seven are interior shafts. Four surface shafts and three interior shafts are now active and, excepting the recently completed new main ore-hoisting shaft, the remainder are either abandoned, or are used for passes or for ventilation. The new shaft bottoms 60 feet below the 3,050 level, but there is much work to be done before it is placed in service. The term 'shaft practice' is intended to include shaft construction and a general treatment o typical equipment. It is a large subject for an organization the size of Hollinger and this paper is intended only to present the salient features. The writer wishes to thank the management for permission to publish this information and to acknowledge the advice and criticism o A. G. Irving, chief engineer, and the willing co-operation of other members of the Hollinger staff.

Jan 1, 1939

By F. E. Block

The reaction between calcined dolomite and ferrosilicon has been studies with the aim of developing a continuous process for magnesium production. Small-scale tests were made in vacuum retorts similar to those used in the vacuum retort process as developed by Pidgeon (1)2/ and operated during the period of World War II in several Government-owned plants. Factors investigated with respect to the silicon efficiency were the reaction temperature, reaction time, amount of excess dolomite in the charge, and effect of adding sodium silicate to the charge to serve as a binder. Additional laboratory tests were made to study the reaction at elevated temperature but at atmospheric pressure. Silicon efficiencies exceeding 80 percent were found to result when operating in the temperature range from 1,750° to 1,800° C. for periods of 20 to 30 minutes.

Jan 1, 1956

This modern plant consists of a battery of 72 Otto Wilputte Compound Under-jet Ovens with extensive plant for the recovery by-products. The ovens produce 9000 tons of furnace coke per week together with some 17,000,000 cub. ft. of coke oven gas, which is used for heating purposes throughout the works and for heating the ovens.Coal is supplied from the, company's colliel'ies and is stored under a Coal Handling Bridge of 264 ft. span and 365 ft. overall, capable of handling 250 tons per hour. The coal storage space of 1600 ft. can. be extended to a maximum of 2800 ft.Preparation of the coal for coking involves fine grinding which is carried out as follows:-Coal is dumped from rail waggons on to a conveyer belt which delivers it to a 12 ft. x 22 ft. Bradford Breaker, with a capacity of 400 tons per hour. The coal, then approximately 4 in. in size, passes, to the mixing bins; and after careful blending is reduced in the,hammer mills to a fineness suitable for the ovens.The fire coal is elevated to the main storage bin over the battery for subsequent charging by electric larry car. The average cokingtime is 15 hrs. 36 mins. At the end of ,this period the doors, are removed and the coke pushed from the oven by a mm. The coke, is, then quenched with fresh, water and sent to the Blast Furnace in 50-ton Copper Waggons.The gas is exhausted from the ovens by Brown Boveri turbine, exhausters of 23,000. cub, ft, per min. capacity. Exhaust steam from these is used for various. purposes in the By-Product plant. After removing the last traces of tar by Electrostatic Precipitators', the gas is bubbled through sulphuric acid, the ammonia forming ammonium sulphate, which is subsequently washed, dried and bagged for sa,le as a fertilizer. The gas then goes to the Benzol Scrubber Towers, where benzol and other derivatives are recovered and later redistilled and purified. The cleaned gas is then piped to the main works for heating purposes, being used with tar to fire the steel furnaces, and also the soaking pits and reheating furnaces.BLAST FURNACES.The company is at present operating two Blast Furnaces of 800, and 1000 tons nominal daily capacity respectively. The latter was...

Jan 1, 1938

By Y. Zhang, M. Yekich, C. Zhou, C. Jobes, J. Galanko, D. Tuchman, J. Srednicki, J. Carr

The continuous personal dust monitor (CPDM) is an essential instrument for working in hazardous environments, is used to monitor real-time coal dust exposure, and is mandated by the Mine Safety and Health Administration (MSHA) for underground coal mines. Researchers from the National Institute for Occupational Safety and Health (NIOSH) found that it is possible for electromagnetic interference (EMI) between a CPDM and a proximity detection system (PDS) to occur. Various approaches have been taken by researchers and manufacturers to address this EMI issue. Administrative controls were recommended to keep the CPDM six inches away from the wearable PDS device. Shielding pouches were made to contain the electromagnetic (EM) emission from the CPDM. Metal shielding was added to major EM emitting components. EMI filtering with large capacitors was introduced to mitigate EMI. Most recently, a novel magnetic-field-cancellation-based approach was developed and achieved remarkable results. In this paper, we provide a comparison between these approaches. The pros and cons of each approach are presented and discussed, so that mining device manufacturers and operators can best evaluate the technology and controls that improve the health and safety of mine workers.

Feb 1, 2023

By H. W. Gillett

MAINTENANCE of membership by the technical so¬cieties and the activity of these societies in spite of the adverse business situation have been noteworthy. This forcibly brings home the fact that industry recognizes that sound technical guidance is well worth its cost. The numerous difficulties and losses due to defects of various kinds arising from gas-metal reactions are now generally recognized and interest in these problems is widespread. The forthcoming A. I. M. E. round-table discussion of gas-metal problems will do much to clarify the situation and will permit us to assay our present knowledge and to suggest the proper direction for profitable future research. "The Age Hardening of Metal" was the title of the annual I. M. D. lecture delivered by Dr. Paul D. Merica. A critical review of the known facts relating to age-hardening phenomena was first given, followed by the presentation of a theory correlating the detailed observations which have been made regarding the mechanism of the hardening.

Jan 1, 1933