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Current mine production planning, scheduling, and allocation of resources are based on mathematical programming models. In practice, the optimized solution cannot be attained without examining all possible combinations and permutations of the extraction sequence. Operations research methods have limited applications in large-scale surface mining operations because the number of variables becomes too large. The primary objective of this study is to develop and implement a hybrid simulation framework for the open pit scheduling problem. The paper investigates the dynamics of open pit geometry and the subsequent material movement as a continuous system described by time-dependent differential equations. The continuous open pit simulator (COPS) implemented in MATLAB, based on modified elliptical frustum is used to model the evolution of open pit geometry in time and space. Discrete open pit simulator (DOPS) mimics the periodic expansion of the open pit layouts. Function approximation of the discrete simulated push-backs provides the means to convert the set of partial differential equations (PDEs), capturing the dynamics of open pit layouts, to a system of ordinary differential equations (ODEs). Numerical integration with the Runge-Kutta scheme yields the trajectory of the pit geometry over time with the respective volume of materials and the net present value (NPV) of the mining operation. A case study of an iron ore mine with 114 000 blocks was carried out to verify and validate the model. The optimized pit limit was designed using Lerchs-Grossman?s algorithm. The best-case annual schedule, generated by the shells node in Whittle Four-X yielded an NPV of $449 million over a 21-year mine life at a discount rate of 10% per annum. DOPS best scenario out of 2 500 simulation iterations resulted in an NPV of $443 million and COPS yielded an NPV of $440 million over the same time span. The hybrid simulation model is the basis for future research using reinforcement learning based on goal-directed intelligent agents.

Jan 1, 2008

By S. B. Christy

This report on the electrodeposition of gold and silver from cyanide solutions represents work that has occupied my time at intervals during the past 20 years. The investigation has been carried on simultaneously with my duties as professor of mining and metallurgy of the University of California. During shis long investigation I have been assisted in the details of the work by, a number of my former students, acting in turn as assistants. Particular mention in this connection is due W. H. Hilton, who graduated in 1900; C. T. Dozier, 1902; N. C. Stines, 1905; H. N. Herrick, 1907, and L. C. Uren, 1911. It is impossible to publish full details of the many thousands of experiments performed. Effort has been made to present only the essential data. Wherever possible, the results of the experiments have been expressed in diagrammatic form by curves showing the relation between the simultaneous variables of the experiments. It is necessary to show, as nearly as may be, the state of the art. This is difficult because of the meager literature on electrodeposition in the cyanide process; hence resort must be had to the specifications and claims of patents, most of which seem never to have been applied on a working scale. Such information consequently can not be taken at its face value. Expressing the essential ideas evolved in such specifications is no easy task. Clearly, in quoting from patent records it is not ·feasible to enumerate all of the specifications or the claims allowed the inventors. A statement of the chief contributions to the art in the patent cited must suffice. Legal details, of course, must be obtained from the original patent. In the study of patent literature, when one compares the ardent hopes of the inventors with the results realized from their efforts, it becomes clear that in the development of an art no one man contributes everything. Each subsequent inventor stands on the shoulders of the one who has gone before. It is only through the summation of the contributions of many inventors that the art as a whole prospers. On October 19, 1887, a British patent was granted to McArthur and Forrest for the use of dilute cyanide solutions for treating gold and silver ores. The rapid extension of this process, in various forms, all over the world, has almost revolutionized the treatment of ores containing precious metals. It is a remarkable fact, however, that long before this patent was granted there was issued, on February 5, 1867, to J. H. Rae, U. S. patent 61866, for an electrocyanide process. Thus a method of electrodeposition from cyanide solutions used for treating ores was invented 20 years before the McArthur and Forrest patent .was granted, although the process did not come into general use. On May 24, 1889, U. S. patent 403202 was granted to McArthur and Forrest for the use of zinc shavings for removing gold and silver from cyanide solutions. The use of finely divided zinc is still the standard method for recovering 'gold and silver from cyanide solutions. Since this patent was granted, many attempts have been made to replace the precipitation upon the zinc by methods of electrodeposition. It is the purpose of this report to give an outline of some of these methods, as well as to show the relative advantages and disadvantages of the zinc and the electrical methods of recovering gold and silver from cyanide solutions.

Jan 1, 1919

In-pit crushing and conveying (IPCC) is being increasingly considered as an alternative to traditional truck-shovel mining methods. The move towards IPCC is driven by a number of factors including the potential to reduce greenhouse gas emissions, the availability of skilled labour and the need to increase extraction rates to levels that present significant challenges to traditional methods.When considering the relative performance of IPCC and truck-shovel methods, the outcome can be inadvertently impacted by either the use of different simulation approaches, or techniques that do not adequately model the processes in sufficient detail.A simulation approach is proposed that models both IPCC and truck-shovel using the same software platform and is capable of functioning at a wide range of resolutions from life-of-mine scale through to second-by-second asset tracking level. The simulation framework also holds models of processing equipment and hence the mining simulations can be extended to gauge the impact on downstream plant.The approach, known as mine-process operational simulation (MPOS), can be tailored to the level of information available and hence the type of study required, ie order of magnitude, prefeasibility, feasibility, or detailed design.Using information from block models and a range of detailed equipment and process models, MPOS can span major system discontinuities, typified by the mine-plant interface, to allow the estimation of final mine and plant product specifications.

Dec 6, 2010

This Bureau of Mines report is a reference manual of procedures used by the Bureau's Twin Cities Mining Research Center for obtaining rock properties. Included in the report are discussions on the usage of each property, descriptions of the general test methods for obtaining the properties, and instructions for performing the tests. The Instructions embrace details of the specimen configuration, test apparatus, test procedure, test conditions, and calculations needed to achieve satisfactory results. Although the procedures presented in this reference manual generally conform to recommendations of the ASTM Administrative Committee on Standards, they are not purported to be standards.

Jan 1, 1974

By Viktor Lishchuk, Olof Martinsson, Tobias E. Bauer, Elena Haller

Freely accessible and non-confidential real-life geological data sets from mineral deposits are desirable for the wide range of applications in research and education. However, publicly available statistical data are limited in their number and quality—they contain reduced information about geological, geophysical, geotechnical, chemical, mineralogical, and other relevant properties of deposits. This makes such data insufficient for scientific purposes. However, the amount of geological knowledge obtained for a variety of deposits in the past allows the construction of an idealized synthetic ore body model using analytical approach. Such a model could be used for education purposes and testing basic scientific theories, e.g., visualization of deposit structure; teaching sampling strategies; testing new algorithms for mine planning; or comparing geostatistical modeling methods. This paper presents an analytical approach to simulate volcanic massive sulfide (VMS) deposits and shows how synthetic deposit model can be constructed and further used for studying sampling with drilling and simulating folding and faulting.

Jan 14, 2021

By Robert L. Brooks

This paper is intended for companies at all levels of the Explosive Industry and in particular, those that do not have a risk manager. It is strictly informational in nature and no reference is made, or intended towards any existing insurance company or agency.

Jan 1, 1993

By Jiakai Zhang

Many postconsumer electrical and electronic equipment wastes contain a considerable amount of rare earth elements (REEs); however, the current level of REE recycling from them is limited (<1%). Neodymium–iron–boron (NdFeB) magnets, used at both small- and large-scale, from computer hard disk drives and small tools to wind turbines and cars, are a good example of such waste materials that contain high content of neodymium (Nd) and dysprosium (Dy). These elements are considered critical metals because they are the main building block of emerging green technologies that will allow for GHG emission reductions. Because demand for these green products is increasing around the world, the demand for REEs is increasing quickly, putting their supply at risk in the near future. Thus, it is critical to develop efficient, robust, and cost-effective processes to recycle these elements from this class of electronic waste materials. Here, we performed a thorough characterization of a N52–NdFeB magnet to identify its composition, crystal structure, and morphology. Furthermore, we developed an efficient hydrometallurgical process to extract Nd and Dy with high efficiency (more than 95%).

By J. Kempken, R. Degel, J. Kunze, R. König

The FeNi technology is currently dominated by high-power submerged arc furnaces, often designed as smelter as "two-inline-solution". To achieve the intended high efficiency, state-of-the-art design in good correlation with ores and reductants and an integrated layout of the whole plant is of great importance. An introduction will be given to general aspects in the production FeNi, plus a detailed overview of design principles for large FeNi smelters and finally some examples of innovations and research projects concerning Fe-Ni.

Jan 1, 2007

By H. M. Woodroffe, H. K. Conn, S. J. Rice

World production of asbestos is estimated to be at a current level of almost 3.5 million tons, having more than doubled in the past ten years. A substantial part of the increase has been due to a rapid expansion in the Soviet Union. Production from that country during 1964 is estimated at 1.5 million tons and, as a consequence, Russia has displaced Canada as the leading world producer. Although traditionally the asbestos mining industry has been centered near Sverdlovsk in the Urals, two new producing areas have been under development for some time. It is expected that a new mine will be in operation in 1965 near Kiembi, Kazakhstan, some 300 miles south of Sverdlovsk, and an- other mine at Aktrovak in Tannu-Tuva, west of Lake Baikal. These developments will provide a significant increase in the production capability of Russia. Although internal consumption is expected to increase with the addition of new asbestos- cement producing facilities now under construction in Russia, there is some speculation that exports will also increase.

Jan 2, 1965

Seventy-three of the 90 naturally occurring elements that are found in the earth&apos;s crust are metals or metalloids. The quantities of metals used annually in the United States range from about 100 million metric tons (steel) to a few kilograms (osmium). The recovery of metals from discarded products or industrial process wastes, especially those metals that are used in large quantity, are very expensive, or are unusually toxic, is important to the national economy and to the natural environment. From its inception in 1910, the U.S. Bureau of Mines (USBM) has been the Government&apos;s prime source of information on metals recycling, as well as a major innovator in recycling technology. Statistical data on scrap generation and processing have been summarized annually for many years in the USBM&apos;s Minerals Yearbook. Most of the data for individual metals discussed in this report were extracted from that publication.

Jan 1, 1993

By E. J. Gleim

The Bureau of Mines customarily publishes lists of equipment meeting its safety standards to keep the mining industry informed as to the development and availability of mining equipment that can be used safely. The present list supplements Bulletin 543, Permissible Mine Equipment Approved to January 1, 1953, as well as Information Circular 7722, Permissible Mine Equipment Approved During the Calendar Years 1953-54. Because standards have been revised and new ones added by the Bureau, this list contains classes of equipment not previously covered.

Jan 1, 1958

By Dorothy B. Niell, O&apos

In its first three years of operations, the in-house programs of the continental Shelf Division of the Marine Minerals Technology Center (MMTC/CSD) have focused on the development of drill systems - technology and the improvement of techniques and applications of reconnaissance methods to marine mineral deposit characterization. Many of the technological advances made to date have been in direct response to specific requests from industry for drill systems needs, and from federal and state agencies seeking technical support for various research efforts. These cooperative programs have proven to be an extremely efficient and effective way for the MMTC to achieve some of the main program goals that were established for the organization at the outset: primarily, to encourage and assist U.S. industry in marine minerals research activities and to encourage cooperative work among research institutions, government agencies, and industry. The primary achievements of the MMTC/CSD to date include the development of the Remote Placer Drill System for rapid reconnaissance drilling of precious metal placer deposits (including both pneumatic prototype and hydraulic production

Jan 1, 1991

By M. du Toit

Cromanite?is a new high-strength austenitic stainless steel developed by Columbus Stainless. It contains approximately 19 percent chromium, 10 per cent manganese and 0,5 per cent nitrogen. Cromanite can be welded successfully, but due to the high nitrogen content of the base metal, certain precautions have to be taken to ensure sound welds with the desired combination of properties. Although no matching filler metals are currently available, Cromanite can be welded using a range of commercially available stainless steel welding consumables. Welds produced using E309L, E307, E307Si and E312 filler wires are resistant to hot cracking and the formation of nitrogen-induced porosity, but the hardness, strength, ductility and toughness of the welds are generally inferior to those of the base metal. In applications where full use is made of Cromanite?s high strength, welds with matching strength levels would be required. In wear applications, where Cromanite is used primarily for its work-hardening properties and corrosion resistance, lower strength welds would probably be acceptable. Welds produced using E307 filler metal demonstrate the best combination of properties for use in wear applications. The welds display high rates of work-hardening that would result in increases in hardness and strength when subjected to abrasive or high impact environments.

Jan 1, 1999

By A. A. Jonke

The combustion of fossil fuels in a fluidized bed of calcined limestone particles is a potentially efficient and economically attractive process for the generation of steam for electric power production and other uses. The process results in greatly reduced emissions of both sulfur oxide and nitrogen oxide pollutants. Development work, evaluations and design studies are being carried out by various organizations under contract with the U. S. Environmental Protection Agency and the Dept. of Interior (Office of Coal Research). The AEC&apos;s Argonne National Laboratory is one of the principal participants in the development program under interagency agreements with EPA and OCR. This paper covers the principal reasons for developing fluidized-bed combustion, its advantages and disadvantages over conventional combustion methods, and some of the potential applications of the process. The participants in the multi-organizational program, the sponsoring agencies, the general status of development of the overall project, and the chief program areas that still require resolution are discussed. The main features of the program of work at Argonne National Laboratory and the results achieved so far are also included.

Jan 1, 1974

By D. W. Davis, P. Landais, L. J. Robb

Abstract -Nodules of carbonaceous matter have been observed in several Archaean peraluminous granites adjoining the gold- and uranium-bearing Witwatersrand Basin. These nodules, which resemble solid bitumen, usually replace uraninite or uranothorite and are paragenetically late. They show many similarities to kerogen seams and nodules associated with the conglomerate horizons in the Witwatersrand Basin, including composition, maturation, intimate association with uraninite, and a late paragenesis. U-Pb isotope ratios for granite-hosted and Witwatersrand kerogens define a single, albeit somewhat diffuse, Pb-loss discordia suggesting an upper intercept age of circa 2300 Ma. Carbon isotope analysis indicates lighter ?13C values for the granite-hosted nodules than for the sediment-hosted kerogen seams. Raman spectroscopy indicates that granite-hosted kerogen is more highly ordered than Witwatersrand seam kerogen. A model is presented which links the granitoid­ and sediment-hosted organic matter to an event of oil generation in the Witwatersrand Basin circa 2300 Ma ago. Light hydrocarbons migrated through the sediments and into underlying/adjacent granitic rocks, undergoing polymerization and accumulation in response to radiation accompanying the presence of high-uranium phases.

Jan 1, 1994

By J. H. East, D. Harrington

"INTRODUCTION The tremendous expansion of industry during the war and the unprecedented demands for metals and minerals are reflected in the production and use of explosives during that period. The increased use of explosives brought added safety problems to industry because of the necessity of using men as blasters who were not entirely familiar with and some who were totally unfamiliar with the characteristics of some or all of the various explosives. A discussion of the characteristics of the ordinary types of explosives used in: industry should assist in giving a better understanding of the hazards attending their use. Explosives are compounded so they may be used with reasonable safety provided the user understands and follows the procedure recognized as standard safety practice. Short cuts and the failure to understand and use recognized safe practices, as well as the selection of explosives unstited for the work at hand, are all part of the safety problem,The extent to which explosives are used in the United States is shown by a study of the statistics compiled by the Bureau of Mines 4/ regarding them. Some of these statistics are shown below and serve as an indicator of the tremendous number of men engaged in the transportation, storage, and use of explosives. Theme men are exposed to the inherent hazards attending this occupation and they should be familiar with the recognized safe practices relative to explosives."

Sep 1, 1946

By Gabriel K. Nzulu, Lars Hultman, Per Eklund, Martin Magnuson, Abu Yaya, Prosper M. Nude, Hans Högberg

Pyrite is the most common among the group of sulfide minerals in the Earth and abundant in most geological settings. This gangue mineral in association with garnet, hematite, magnetite, and other sulfide minerals acts as an indicator mineral in the Kubi concession of the Asante Gold corporation in Ghana. X-ray diffraction (XRD), air annealing in a furnace, energydispersive x-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS) were applied to investigate the crystal structure, identify individual elements, permanence, transformation, and chemical/electronic properties of such pyrite. The study aims to identify individual elements and to gain an understanding of the surface reaction mechanisms, as well as the properties of precipitated pyrite particles observed during the hydrothermal formation of the ore deposit. XRD shows that pristine and annealed samples contain some hematite and quartz besides pyrite. Results from air annealing indicate that the relationship between pyrite and hematite-magnetite is controlled by temperature. EDX reveals that the sample has O and C as contaminants, while XPS in addition reveals Ba, Au, P, Al, and N. These elements are attributed to pyrite that bonds metallically or covalently to neighboring ligands/impurity minerals such as oxides, chalcogenide sulfides, as well as the gangue alteration minerals of magnetite and hematite in the pyrite sample. These findings suggest that during the hydrothermal flow regime, pyrite, pathfinder elements, and impurity minerals/metals were in contact with quartz minerals before undergoing hematite transformation, which thus becomes an indicator mineral in the Kubi gold concession.

Feb 27, 2024

By Louise Corriveau, Bronwyn Azar, Valerie A. Jackson, Luke Ootes, Jeff Harris

We use the results of new bedrock mapping, combined with geochemical point data and airborne radiometric data (in particular equivalent uranium concentrations) to help determine which geological units in the Paleoproterozoic Great Bear magmatic zone (GBmz) contain elevated uranium. The data collectively indicate that the highest primary uranium concentrations are in equigranular granites and subvolcanic/volcanic porphyries. Notably, these rocks host the majority of known uranium-bearing deposits and/or prospects in the GBmz. We speculate that the uranium in these deposits/prospects was derived from nearby, uranium-enriched rocks and was mobilized by much younger, circulating hydrothermal fluids. Sedimentary rocks of the Thelon and Dismal Lakes groups unconformably overlie the GBmz and are known to host unconformity-type and sandstone-hosted uranium prospects. Most likely, the uraniumenriched rocks of the GBmz acted as a uranium donor to these overlying sedimentary basins. The method of investigation employed in this study may be applicable to other ‘granitic’ terrains in order to identify regions with favourable rocks for uranium exploration.

Jan 1, 2013

By Zhiguo Chang, QINGXIANG CAI, Ebelia Manda, IZHAR MITHAL JISKANI, XIANG LU, Wei Zhou, Saleem Raza Chalgri

The concept of mine safety is highlighted in the literature of sustainable mining but not extensively discussed. This study analyzes various aspects of underground and surface mine safety and emphasizes its importance in the context of sustainable mining. More specifically, this research attempts to find the relationship between mine hazards and demographic characteristics, examine and compare the perceptual difference among miners, and determine the impact of mine hazards on workplace safety and safety climate. Descriptive analysis, chi-square test, independent samples t test, and linear regression modeling were conducted to achieve study objectives. Results confirmed that mine hazards were significantly associated with age and experience. Miners perceived lower levels of management safety practices, followed by supervisor safety, coworker safety, and job safety. The analysis showed that underground miners reported lower safety scores than surface miners. There was a statistically significant difference between miners’ perception of safety climate (p < 0.05). The results showed that the higher prevalence of mine hazards predicts poor workplace safety and a low safety climate. The regression models revealed that mine hazards have a significant effect on workplace safety (p < 0.05) and safety climate (p < 0.05). In conclusion, the distinctive model of mine safety presented here contributes to the monitoring and design of comprehensive safety interventions and helps to better understand how certain factors interact on multiple levels to influence the overall safety of the industry. In this study, some suggestions are put forward to provide directions to develop a sustainable mine safety system.

Mar 27, 2020

By John J. Gillis

There is an ongoing battle to gain general acceptance of fossil fuel byproducts as safe, economical and useful agro-industrial materials. Despite that, the US ash industry is witnessing a steady growth in the volume of coal burned, along with the production of greatly refined, higher-quality ash particulates. There are two principal reasons for this. Economics have caused an increasing number of US electric utilities to convert from oil-burning to coal-burning. And the Federal government has tightened specifications on fly/bottom ash production quality. Hence, it must be noted that new and more stringent Federal regulations were implemented in 1980. The resultant ash particulates are finer, more compact, and less heavy than in previous years. Additionally, the first shift from oil to coal in the US was initiated in December, 1979 by the New England Power Co. in Massachusetts. Coal is the most widely-distributed fuel in the US. And it is found in 38 states. The wide availability of this fossil fuel and its general cost-efficiency, coupled with the undaunted move of US electric utilities toward nuclear power, are major factors affecting the current statistics on ash generation (65.4 x 106 million tons). Interest in the use of coal in power plants is creating a unique ash disposal and use situation for ash producers as well as the Federal government. There are growing quantities of fly/bottom ash residue. Ash producers must decide how this byproduct can be dealt with effectively and profitably. At the same time, government agencies such as the US Environmental Protection Agency (EPA), are commissioned by Congress to assure that solid, liquid, or gaseous material released into the environment is not harmful or offensive to human health and the environment. Additionally, the Federal government is often responsible for establishing and enforcing guidelines and standards governing the use of recycled materials. Several standards and guidelines governing the properties and use of ash in the US have been established by governmental agencies as well as by the ash industry itself. Of these, some have been developed for ash use by a specific federal agency. Others apply to the entire industry. The following is a brief identification of the major specifications for fossil fuel ash: • US Corps of Engineers - These specifications were first established in 1957. They delineate the physical and chemical requirement for pozzolans used in mass concrete. These specifications applied only to Corps of Engineers&apos; concrete construction projects for locks, dams, and other mass concrete projects until 1977. At that time, a joint effort between the American Society for Testing and Materials and the Federal government produced a modified specification that is now generally applied. The Corps of Engineers&apos; ash, however, retained certain aspects of its specifications for its own use, particularly in the area of handling and shipping fly ash to its own projects. Prior to transporting the fly ash to the corps, all potential sources for the ash must be inspected and approved as a supply source. All silos must be filled, sealed, and tested before the ash is released for shipment. The normal test period for the ash is seven days, although several testings may require up to 28 days. Once the fly ash has been released, it can only be shipped to US Corps of Engineers&apos; projects. All shipments are made with a government inspector present during loading. After a truck or railcar is loaded, the silo is resealed until the next shipment. This procedure requires three silos, and a minimum of 454 t (500 st) each should be considered for each storage unit. All silos are strictly committed to Corps of Engineers&apos; use and are not available for other commercial shipments. • US Bureau of Standards - This Federal agency maintains a standard testing sample of nearly every product used in the US. The accuracy of the fly ash chemical analysis is measured by a regular cement and concrete reference laboratory (CCRL) inspection and based on test results from a standard sample of cement. • US Bureau of Reclamation - This agency pioneered several projects using fly ash and required Federal Standard Certification for pozzolans. • American Society for Testing and Materials (ASTM) - This nongovernmental organization began preparing standards for fly ash sold and used in the cement and concrete industry in 1947, at the urging of ash marketing firms. Current standards define chemical and physical requirements and is entitled, "Fly Ash and Raw or Calcined Natural Pozzolan for Use as a Mineral Admixture in Portland Cement Concrete (C 618-80)." • State Highway Specifications - Led by Alabama, many states are moving toward permitting - and in some cases requiring-the use of fly ash in portland cement concrete and with lime for base stabilization projects for roads and highways. • Federal Aviation Administration (FAA) - The FAA acts in an advisory capacity. It has final approval on design specifications for airport construction projects. The agency has established a set of guidelines permitting the use of fly ash, and has approved several fly-ash-specific designs. The most current FAA fly ash projects

Jan 8, 1984