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By Harold J. Bennett

The purpose of this study was to develop methods for the financial evaluation of mineral deposits. This includes the selection of the best alternative mining and processing methods and production rates. This was done by performing a financial evaluation through computer simulation using sensitivity and probabilistic risk analysis. The criterion used to measure the relative advantages of these investment and operating alternatives is the discounted-cash-flow rate of return. Included is a description of the theory and methods used in the probabilistic analysis approach, which is based on the premise that the expression of a range of values in establishing an estimate for a parameter is more realistic than the choice of a single value. Numerous simulations are made using randomly selected values of the input parameters resulting in a frequency distribution of the rates of return and their relative probability of occurrence. The sensitivity analysis method is described and combined with the probabilistic analysis to interrelate mineral reserves, capital investments, operating costs, and production rates. The ability to vary these input parameters on successive runs has permitted the selection of the best alternative mining and processing methods and production rates for a given mineral deposit. For illustrative purposes the evaluation of a mineral deposit was performed using three alternative mining and processing methods at three different quantities of resources and various production rates and prices. The computer program used in this analysis was written in FORTRAN II for maximum compatability and should run without modification on most computers having BK (8,000-word) core memory, a card reader, and printer (120 characters per line).

Jan 1, 1970

By MATTHEW HART, THOMAS BAMFORD, Kamran Esmaeili, MICHAL KOWALCZYK, FILIP MEDINAC

Improved haul-road conditions can have a positive impact on mine operations, resulting in heightened safety, productivity gains, longer tire life and lower maintenance costs. For these reasons, a monitoring program is required to ensure the operational efficiency of the haul roads. Currently, at Bald Mountain Mine, monthly site severity studies, ad hoc inspections by frontline supervisors or operator feedback reporting are used to assess road conditions. These methods are subjective and provide low temporal resolution data. This case study presents novel unmanned aerial vehicle (UAV) technologies, applied on a critical section of haul road at Bald Mountain, to showcase the potential for monitoring haul roads. The results show that orthophotos and digital elevation models can be used to assess the road smoothness condition and to check the road design compliance. Moreover, the aerial mapping allows detection of surface water, rock spillage and potholes on the road that can be quickly repaired/removed by the dedicated road maintenance team.

By T. A. Rickard

Slovenliness is as reprehensible in words as in clothes. Much writing that we recognize as poor in style is merely sloppy. Just as some students postpone the necessary shave or forget to change their collars, so young engineers in writing drop their articles, definite and indefinite, or omit prepositions where they are required, possibly to compensate for these they use unnecessarily The work will begin [on] Saturday. The work will begin [on] Saturday. `Influenza seriously affected many mines [during] the last three months. Flotation in America [during] the last two years has made tremendous strides. Construction of the mill started [on] August 12, 1915, at which time 75% of the excavation was completed. The idea I wish to convey is [that] there are mineral deposits to which the present law applies badly. For this reason, if there was [for] no other, the ownership of the ore below and [of] the surface above should go together. When a unit of mapping is furnished, be the unit a claim or [a] group of claims, it is necessary .. . A fully stocked store was started in Park City and all employees [were] sold merchandise on a strictly cost basis. The word "merchandise" is left without government or agreement. I suggest: ". . . and merchandise] was sold to all the employees on a strictly cash basis.". The verb `be' is serving concurrently both as a principal and as an auxiliary in the following: At first the work was interesting and [was] liked by most of the men. The sulphide ore was more complex or [was] milled at an increased cost. The failure to repeat tie auxiliary verb in successive clauses is a common error, as in The filter is filled with liquid allowed to empty, and then ignited.

Jan 1, 1931

By Andre Zingano

An underground mine using room and pillar and retreat mining methods was developed during the 1950?s. In 2009 an open cast mine was opened in the same reserve with the objective of mining five coal seams including the one previously mined. Recently, a series of slope failures were detected at the open cast mine. The surface mine map was overlain on the underground mine map, and it was observed that the slope failures were located above a retreat mined area where the overburden had caved and the ground subsided. The deformation and displacement attributable to subsidence caused a loss of strength in the overburden strata. The objective of this paper is to study the causes of slope sliding (or failure) due to the ground subsidence of rock layers above oldmined out areas. A map was created to overlay the two mines -- the abandoned underground mine and the active surface mining. Two- and three-dimension numerical modeling was conducted to simulate the slope behavior and to verify whether the mine subsidence was the cause of slope instability. This study indicated that the subsided rock layers were the cause of slope instability and sliding.

Jan 1, 2013

By L. H. Duschak, C. N. Schuette

In the years 1850 to 1923, the United States produced 2,426,000 flasks- (73,600 metric tons) of quicksilver worth $120,500,000. California yielded 2,195,000 flasks of this total; the remainder came from Texas, Oregon, Nevada, and A.rizona. Most of this metal has been extracted from low-grade ores, those containing less than 0.5 per cent mercury or 10 pounds per ton. The finished product or " virgin metal" is made at the mine and shipped in flasks. Quicksilver is unique in being the only metal that is liquid at ordinary temperature. Because of this and other physical and chemical properties, it is perhaps more indispensable to industry than any other metal. On the other hand, the quicksilver industry of the world is of vanishing significance" when compared to the major mineral industries with respect to quantity and value of product, capital invested, or the number of men employed. The peculiar value of quicksilver is due to the fact that in some of its applications no substitute is available and in others the substitutes would be unsatisfactory or extremely expensive. Scarcely a branch of science or industry fails to make some use of mercury or its compounds. As a detonator for explosives, mercury fulminate holds first place and in safety and reliability could be replaced only by the highly expensive silver fulminate.t vThrough its use in detonators and in the metallurgy of the precious metals quicksilver is of special importance to mining. In medicine,in the manufacture of electrical apparatus, the production of pigments and antifouling paints, and the general field of experimental science quicksilver is equally indispensable.

Jan 1, 1925

By S McKnight, L Koroznikova, J Begelhole

"This paper outlines a simple methodology for iron ore characterisation. Iron ores commonly contain a range of iron oxides with varying iron content along with generally minor quantities of lighter silicate gangue phases, giving rise to density variations. Companies tend to rely on heavy liquid separation (HLS) in the evaluation of samples arising from exploration, mining or metallurgical processes. Heavy suspension separation (HSS), a simple laboratory technique of density fractionation, employing suspensions of fine tungsten carbide (WC) particles in lithium heteropolytungstate (LST) solutions, can be used in the evaluation of iron ore.As part of Arrium Mining’s program to improve its knowledge of ore types being processed in two hematite ore beneficiation plants (OBP), metallurgical evaluation of hematite feed and geometallurgical evaluation for the OBPs has become a major focus.Metallurgical evaluation of the hematite ore ultra-fine size fraction, formally treated as waste but now upgraded by HSS, is a part of Arrium’s program to improve recovery.The HLS method for iron ore characterisation is not generally used as part of routine iron ore feed metallurgical evaluation due to the expense, toxicity and time-consuming nature of the technique. Results show that the HSS method for iron ore characterisation can achieve low-cost, low-toxic separation and can be used on-site to improve turnaround time of results (Begelhole, Jasper and Koroznikova, 2013).Arrium have applied this technique successfully for the past three years to progress process improvement for the two OBP as well as to assist Arrium’s on-site laboratory services, Bureau Veritas in Whyalla.The main objective of this program has been to further develop the HSS procedures using a low-toxicity, high specific gravity (SG) suspension; LST and WC as the dense medium for metallurgical evaluation of ultra-fines.A suspension of a particular density will separate iron ore into two products: a sink fraction (denser iron oxide – hydroxide particles) and float fraction (silicate – iron ore composite particles). A theoretical grade and mass recovery can be calculated, and a grade – mass recovery curve can be constructed for iron.Metallurgical evaluation of the plant feed ultra-fine size fractions are used to improve efficiency of an upgrading plant process. This type of characterisation can be used to prepare feed piles of known processing characteristics, or to benchmark the performance of the process against what can be theoretically achieved.CITATION:Koroznikova, L, Begelhole, J and McKnight, S, 2016. Characterisation of Low-grade Hematite Ore Ultra-fine Size Fraction Particles by Heavy Suspension, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 327–334 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By Clifford S. Gibson

THE Workmen's Compensation Ace defines Silicosis as "a fibrocic condition of the lungs caused by the inhalation of silica dust sufficient co produce a lessened capacity for work". This fibrocic condition muse exhibit a specific appearance in the X-ray picture of the chest-an appearance which is not characteristic of several lung conditions which can cause lessened capacity for work and which are not due co silicosis. The layman is sufficiently familiar with this subject co know chat, as far as our knowledge goes, quartz is one of the principal objectionable factors in the production of this condition. He should also know that silicosis respects neither geographical nor industrial boundaries. It is as much a factor in some industrial processes (e.g. foundry work, sandblasting) as it is in mines handling ores containing quartz. Its development co a recognizable stage is usually a matter of many years. As yet, its cure is unknown. Its prevention is possible in varying degrees. The layman should also know that the development of fibrosis may be accelerated by breathing in, or living in, any atmosphere containing dust. Few normal adults, particularly those above a certain age, have clear lungs, and fibrosis in varying degrees is noted in the farmer, the steel worker, the clerk, and many others in varied occupations. It is not restricted to miners. Medical and industrial journals, and at times the press, are crammed with data pertaining to this subject, much of which is misinformation. This is particularly true of certain !laces where the preventive and compensation measures for the good o those earning their livelihood in an industry in which silicosis may be contracted are not so far advanced as in our own Province. A great many of these publishings are alarming to the layman. They leave him with the impression that he is taking his life in his hands if he elects to work underground, particularly in a gold mine-that he has at once sold his heritage of health and chat sooner or later he will succumb to the ravages of this ailment. Nothing could be farther from the truth. Actually, under present conditions in Ontario mines, a very small percentage of the men employed ever become impaired by silicosis to the extent chat they must withdraw from the industry. I propose to tell you briefly something of this subject as it affects our mines.

Jan 1, 1937

By Frank Haehnig, Kjell-Åke Averstad, Johannes Glückert

"AbstractThe Söderströmstunneln is part of the Citybanan project that is currently under construction in the centre of Stockholm. Main part of the lot Söderströmstunneln is a 300m long immersed tunnel connecting the inner-city islands Södermalm and Riddarholmen. It consists of three tunnel elements that have been immersed in summer 2013. Since the solid bedrock is descending in that area to more then 40m depth, the tunnel elements have been placed and are permanently supported on four pile groups that have been constructed in advance. The common Swedish system of steel core piles has been used to built the pile groups. Drilling and installation of the steel cores piles in free water depth of up to 20m had to be done from a pontoon. The steel core piles are connected with underwater concrete pile caps.IntroductionCitybanan is a new 6km long double track railway tunnel running beneath central Stockholm including two new underground stations Odenplan and Stockholm City. When completed in 2017 commuter trains will have their own tracks through Stockholm, whereas the remaining railway traffic will continue to use the exisiting two tracks (see Fig. 1). This will double the capacity of the railway traffic through Stockholm. The Swedish transport administration Trafikverket is the client for this project. The design and built contract is carried out by the German contractor Züblin Spezialtiefbau GmbH together with their Swedish subsidiary Züblin Scandinavia AS.As the new Citybanan tunnel is in large parts situated below the bedrock level, it can be executed as rocktunnel in the common drill and blast method. Between the two inner-city islands Södermalm and Riddarholmen the tunnel is crossing the Söderström, an arm of the lake Mälaren. Here the bedrock is descending to a deep valley with more then 40m depth. To connect the rock tunnels between these islands a 300m long immersed concrete tunnel supported on pile foundations is currently under construction."

Jan 1, 2014

By Arthur C. McFarlan

There are two distinct coal fields in Kentucky-the Eastern field constituting a part of the Appalachian coal region and the Western field constituting the southern part of the Eastern Interior region. The outcrop pattern of the State is dominated by the Cincinnati arch. Coal-bearing Pennsylvanian strata occupy a low structural position on either flank, preserved thereby from erosion, which in the past has removed these same beds, though a much thinner succession, from the crest of the arch. General geological relationships are shown in figures 1 and 2. On April 13, 1750, Dr. Thomas Walker discovered the first coal recorded in Kentucky. He entered the State through Cumberland Gap (Cave Gap) and found coal a few miles north.

Jan 1, 1944

By WALTER CARROLL

Between cross currents of economic factors and international expediencies the iron and steel industry in 1948 made an outstanding contribution to the general economic picture. Were it not for an unfortunate episode during the month of April involving a temporary shortage of coal, 1948 would have been an all-time record year in output. Exceeded in no previous peacetime year, the production of iron and steel in 1948 totaled some 88,500,000 tons. That it was a worthwhile effort of no small magnitude is evidenced by the fact that in three and one half years following the war, this nation has produced as much steel as in the five years preceding the war. This figure of 88,500,000 tons is 68 per cent greater than that for 1939.

Jan 1, 1949

By S McEachern, J Lowe

An important issue currently facing the mining industry in Australia is the management and cost to the industry and other stakeholders of entry into and exit from towns and their communities. These costs can be environmental, social, economic, political or reputational. The ability of companies to engage the trust of stakeholders, including: communities, governments and investors, is critical, and corporate reputation plays a significant role in this. For the industry to secure a long-term and sustainable future, it must have the technical, business and reputation assets to proceed in a cost-effective, environmentally acceptable and socially supportive way. This research assesses reputation as a critical competitive issue for mining companies, as technology and information make mining more predictable; the physical and human assets of mining companies are less likely to be the critical resource in a Resource Based View model of competitive advantage. The proposition is that in mining today, reputation as it facilitates day-to-day operations, regulatory zeal and access to new mine sites will become the rare, inimitable and valuable resource for mining companies. This paper reports on an ongoing research program to evaluate the impact a mining companyÆs reputation(s), with its various stakeholder groups, has on a companyÆs ability to sustain competitive advantage. Integral to this study is to develop an understanding of the relationships between mining companies and their stakeholders, and the importance of corporate citizenship polices to reputation and hence to corporate sustainability. Through the identification of the drivers of reputation for the various stakeholder groups, a model of reputation formation will be developed and also reputation measures for the mining industry in Australia. The preliminary findings of this research, the results of an industry focus group conducted with representatives from regional mining operations, are reported. The industry focus group was designed to enable a better understanding of who are the main stakeholder groups and how they regard mining companies and to inform the second stage of the research project a Delphi Study of the drivers of reputation by stakeholder groups. The aim of this research is to further the understanding of the relationship between corporate citizenship, reputation and performance in the mining industry, thus assisting companies to strategically manage their corporate citizenship investments.

Jan 1, 2006

By M. Javier

"The impact of mine closure is perceived through a veil of compliance to human laws and regulations rather than the laws and equilibrium of nature. This perception motivates present research. Understanding the causes and effects of mine closure defines levels of responsibility. This understanding evolves from mine closure's legacy. Mine closure is characterized in perpetuity by three aspects: Future liabilities; level of technologies for extraction and, usage of mineral resources. These aspects must be updated to a rationally appropriate level. This paper will address the following questions: Will the minerals remaining in the process of mine closure ever be recovered? Will the mine closure inhibit the availability of minerals for the next generation? How many mines are designed to perform a successful mine closure? Do we close the mines or do we close nature? Is it responsible to continue mine closures as we do them today? Is mine closure a complement of mine operations or a contradiction of mining? Do we need to perform mine closures, yet? This paper reviews mine closure practices and principles with the level of responsibility to nature and for the next generation.PREFACE The planet has irreversible issues to deal with regarding the depletion of mineral resources and contamination occurring from human activities. The population increased exponentially to more than seven billion, this high population with its lifestyles, demands a higher supply of minerals. In spite of these conditions, mining is a vital industry to keep ""civilization"" in society. This is evidenced by what we see around us, in that everything ""made"" in society is directly or indirectly due to mining. Hence, mining cannot be avoided or ignored. Society misunderstands the importance of mining in relation to other activities. At this time, mining is fragmented and economically oriented to supply cheap minerals to a market with peculiar characteristics regarding products that could be designed for recycling and stimulate nature’s equilibrium. These issues add important “variable factors” to the equation, when they are considered as parameters for the next generation. It also raises many questions regarding principles and attitudes about morals and ethics exercised in all anthropogenic activities. The industry's practices have many flourishing paradigms which are subject to a variety of criticisms and observations. Some of these observations will be described in this paper. It is important to clarify in advance a ""normal disclaimer"" about the ""apparent contradiction"" that could take place in the writer's comprehension when we abruptly ""jump to conclusions"". We must remember that we are profiling the future in an arena that demands a better understanding of solutions to problems created by actual mining."

Jan 1, 2015

By E. Lentilucci, A. Dey, X. Liu, A. Datta, S. Ghosh

The segmentation of quarry blast smoke plumes is a crucial research area that has the potential to enhance safety, environmental monitoring, object detection, and regulatory compliance in the mining industry. Smoke plume segmentation can be used to identify the spatial extent and temporal evolution of smoke plumes generated by the blast. This information can be used to improve the understanding of blast dynamics and optimize blast designs. Furthermore, smoke plume segmentation can assist in identifying potential environmental and health hazards associated with the release of smoke and dust particles into the atmosphere during quarry blasts. However, many current smoke plume segmentation algorithms are designed for segmentation of smoke plumes from fires and are not suitable for segmentation of plumes from quarry blasts. The proposed method in this paper leverages the video frame captured before the blast as a stationary background image, which helps to reduce other confuser objects present in the image along with a selfadaptive clustering method. The color channels of the image are utilized based on the different contrast properties of the smoke, with a self-adaptive gradient compensation applied for edge detection of the smoke plume. This approach offers a novel and effective way to segment smoke in quarry blast analysis, with potential applications in the calculation of noxious gas volume and concentration within the plume. Compared to other algorithms, our method improves accuracy, decreases the false alarm rates, and reduces the overall miss rate. Overall, this paper contributes to the research on smoke plume image segmentation, particularly for quarry blast smoke plumes, which possess unique characteristics that require specialized algorithms for accurate segmentation.

Jan 1, 2024

By V. Vogt

During the phosphating of car bodies containing aluminium, the employed phosphating chemicals zinc, manganese and nickel are, for thermodynamic reasons, only used to a limited extent for the desired surface coating. The major proportion of these metals is discharged together with the incidental cryolite-containing phosphating sludges and the rinse water. Commissioned by the German Federal Ministry of Education and Research (BMBF), the Institute of Mineral and Waste Processing, Waste Disposal and Geomechanics at the Clausthal University of Technology has developed a two-stage process for the production-integrated recovery of the dragged out chemicals and for closing the rinse water cycle for Audi AG. During the first stage, the phosphating chemicals are recovered by means of leaching. In the second stage, the rinse water is treated by means of electroflotation followed by an ion exchanger.

Jan 1, 2014

By M R. Drumond

The present work presents a new theoretical interpretation of the flotation process, which can also be applied to other mineral processing physical unit operations. This interpretation is part of the æModelo OperacionalÆ (Operational Model) that was developed as an attempt to establish a new theoretical basis for mineral processing unit operations. In the case of flotation, a book was edited by one of the authors in Brazil (Mass Concentration by Froth Flotation, in Portuguese and Spanish).The model establishes a link between a natural phenomenon (migration of particles from the pulp to the froth) and a real industrial phenomenon (mass concentration by operational interference). In this model, flotation is viewed as a phenomenon of macromolecular mass transport (of particles) between froth and slurry phases. Mechanisms for mass transport and particle flow between phases as a function of the hydrophobic potential in each phase are discussed. By establishing the so-called equilibrium distribution curve between phases it is possible to calculate macroscopic balances that are related to metallurgical results, which in turn are a function of the operational line that is required by the process itself. The number of cleaning stages and their efficiencies can also be determined by simple laboratory-scale experiments.

Jan 1, 2005

By William O. Vanderburg

This paper gives the results of a reconnaissance of the mining districts of Mineral County, Nev., made during the month of June and the first 10 days in October 1936.3/ During the field work virtually all the mining districts in the county were visited and many data were obtained relative to active and inactive properties. The report covers the location of the various mining districts, nature of deposits, ownership, information on past and current activity, data on economic conditions, and general information likely to be useful to operators and investors and others interested in mining. The geology of the deposits is discussed only in a general way. For nearly three-quarters of a century mining tin Mineral County has been the principal if not the only industry of importance. At times it has reached a very low ebb, and at other times it has been attended by the wild excitement that usually accompanies valuable discoveries of precious metals.

Jan 1, 1937

By Gordon W. Hines

This paper, dealing with network planning in an industrial complex, discusses the type and size of project that can be handled on a manual basis. After a review of the fundamentals of network planning, and specifically of the Critical Path Method, the author analyses several different types of projects, each with its own characteristics. Some can be handled in conjunction with a computer, but others can be dealt with equally well without one. Among the projects discussed are a blast furnace reline, the installation of a billet mill flying shear, and routine maintenance-type operations.

Jan 1, 1967

By Thomas J. Albin

This U.S. Bureau of Mines report identifies potential causes of slip-and-fall accidents occurring during surface mine equipment maintenance and describes the relative roles of direct worker behavior and machine design. The relative roles of human behavior and machine design in the causation of slip-and-fall accidents were determined through analysis of accident records, observations of maintenance worker behavior, and evaluation of mine machinery. From these data, relative risk ratios were calculated. Behavior had a relative risk ratio of 1.5; machine design, specifically access systems design, had a relative risk ratio of 2.2. Of the access systems, ladders had the highest relative risk ratio, 7.0. This study suggests that accident intervention would be most profitably made in improving the design of systems used to access maintenance worker areas of mining equipment.

Jan 1, 1990

By C. Zhou, J. Srednicki

Electronic systems have been increasingly used in underground mines to improve mine safety. These electronic systems emit electromagnetic (EM) energy which can adversely impact the performance of other electronic systems nearby and thus should be characterized. Researchers at the National Institute for Occupational Safety and Health (NIOSH) characterized the magnetic fields emitted from devices that can potentially interfere with the performance of proximity detection systems (PDSs) and compared the emission levels of these devices to the susceptibility of PDSs. In this paper, we present our measurement results pertaining to this effort. Particularly, magnetic fields emitted from the different orientations of a powered air purifying respirator (PAPR) and two lite trackers are evaluated based on the RE101 protocol specified in the MIL-STD-461G standard. The results show that both devices emit strong magnetic fields which strongly depend on the orientation of the devices. At some frequencies, the maximum emission levels from the two devices exceed both the emission limit given in MIL-STD-461G and the maximum magnetic fields that a PDS can withstand without a failure. The results and findings in this paper can help the mining industry better understand electromagnetic interference (EMI) underground and provide critical scientific data that support mining-specific recommendations to address EMI-related challenges.

Feb 1, 2023

By Arno C. Fieldner

Six years ago, I addressed the annual meeting of the American Society for Testing Materials on "Fuels of Today and Tomorrow."3/ Since then, our country has been drawn into another great war of veritably global extent, with unprecedented demands on fuels, foods, and materials in general. My purpose in this address is to review the changes in fuel supply and demand since 1937 and to give you my views on the outlook for the future. CONDITIONS IN. 1237 Daring 1936 the United States produced and consumed one-third of the world production of coal, two-thirds of the petroleum, and about 95 percent of the natural gas. Two-thirds of the oil produced in all countries since the discovery well was drilled in 1859 had come from American wells. With the exception of the three depression years 1931, 1932, and 1933, new oil reserves were being discovered since 1924 well in excess of our increasing rate of consumption. Discoveries of natural gas, likewise, were tremendous in volume, and this fuel was being transported to most parts of the country by pipe lines; some of them more than 1,000 miles long. We had all kinds of mineral fuels in abundance and at prices that did not stint anyone in the maximum utilization of the mechanical devices that were being developed on every hand. No one suspected that the time might come in a few years when, gasoline would be doled out to some of us at the rate of 1-1/2 gallons a week or that many of our fuel-oil furnaces would have to be converted to burn coal. Of course, these restrictions are due to unusual war conditions, such as lack of coastwise tanker transportation, unprecedented demand for aviation gasoline, and the shortage of rubber for automotive tires. However, these shortages do call our attention to the vital part of petroleum reserves in our country's future position among nations. Therefore, it is of special interest to review briefly the relations of recent supply and demand with respect to our various mineral fuels.

Jan 1, 1943