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By Steve Axen

In situ mining is now considered an alternative mining method for some ore bodies. The in situ operation consists of a well field designed from reservoir properties and geological information; the wells for such a field are then drilled, cased, and cemented, using good designs and practices to eliminate future problems. Injection and production (recovery) systems are required to be corrosion resistant. Hand in hand with the mining operation is the metal extraction plant, the entire operation offering an environmentally acceptable method for metal recovery. Great opportunity exists in this field for mineral engineers; presently, they must borrow knowledge from other fields, since the schools have not yet addressed this specialty.

Jan 1, 1979

By Edwin S. Smith

One of the many responsibilities of mining engineers and mill superintendents is to provide for the safe and economic disposal of wastes (or tailings) remaining after a mineral has been extracted from an ore. The cost of disposal of these tailings exerts a considerable influence on the minimum grade of ore extracted from the mine. It varies to a great extent with each project and is dependent on many diverse factors, such as the local topographical, meteorolgical, geological and seismological conditions together with the applicable water pollution laws of the area. The process used to extract a mineral from an ore determines the physical characteristics of the tailings and thus is one of the more important factors to be considered when planning disposal facilities. Today's trends .in ore-processing operations complicate the problems of waste disposal: recently developed extraction methods result in the production of finer tailings, the use of lower grade ores produces greater volumes of wastes, while the enhanced land values in the vicinity of industrial plants preclude the former practice of spreading wastes laterally and force the expansion of waste desposits upwards to greater heights. The frequent occurrence of stability problems in waste deposits indicates that many mining organizations may not be employing current soil mechanics concepts and practices. One of the most spectacular, and often most disastrous, types of tailings dike failure is that resulting from liquefaction of the fine particles combined with a breach of the main retaining dike.

Jan 1, 1967

By N. Santa, V. Salinas

"Printed circuit boards are potentially recyclable materials. Developing suitable methodologies for proper disposal and better utilization, brings major environmental and economic benefits. A methodology for copper recovery using heat treatment before conventional leaching is carried out. A comparison between conventional methodology and the one that includes incineration treatment is presented. It concludes about results and differences in terms of the percentage of copper leached over time. INTRODUCTION The rapid proliferation of electronic devices in the past two decades, has forced researchers to find a solution for one of the most toxic and hazardous materials, the printed circuit boards (Ghosh et al, 2015). For this, countless techniques have been developed, the methodologies includes hydrometallurgy, pirometallurgy, electrometallurgy or a combination between all of them. The amount of precious and base metals in its composition are very attractive and usable to implement methodologies that allow maximum recovery and recycling. This subject has been extensively studied and researched in order to provide solutions to the great problems generated by incorrect final disposal of this waste. Over 150 articles have been widely published in the last 15 years, covering large areas such as characterization of discarded printed circuit boards, health risks associated with processing and different routes of recycling have been analyzed to provide an overview understanding this issue (Ghosh et al, 2015). (Oh et al, 2003) performed a selective leaching of valuable metals from waste printed circuit boards by size reduction, magnetic and electrostatic separation, also leaching with sulfuric acid and hydrogen peroxide, achieving 95 \% of copper extraction. (Chaverra Arias, 2014) proposed a similar methodology to extract copper from electrical and electronic waste, performing similar processes and applying metallic copper electrowining as well as copper oxychloride precipitation. (Silvas et al, 2015) used hydrometallurgical processes for recycling printed circuit boards applying physical processing and copper extraction by selective leaching. (Kumar et al. 2014) conducted a leaching of metals from waste printed circuit boards using sulfuric and nitric acids. Also there have been proposed various methods for recovery of different metals including applying multiple metallurgical techniques that involve both living organisms and high temperature processes such as pyrometallurgical. The printed circuit boards are a very important source of copper, according to several authors mentioned above, the amount of copper on a printed circuit board can reach about 20 \%, because copper is responsible of establishing a conductive layer that will enable the connection between electrical and electronic components. This document proposes a methodology for recycling printed circuit boards and extract copper by selective leaching. The process that is carried out consist in a preliminary characterization and mechanical separation which will condition the material for further hydrometallurgical treatment that includes leaching in nitric acid media 3M."

Jan 1, 2017

By Harry Elkin

Control of coal dust has long been an important aspect in the conventional mining of coal; the main reasons being from a health and disaster standpoint. With the advent, of mechanized longwall mining, the control of dust has required more attention due to the high extraction rate common to most longwall systems. The purpose of this paper will be to describe the dust abatement activities of the longwall operation at Sunnyside. Kaiser-Steel Corporation has three mires located at Sunnyside, Utah, with a total production averaging 6,800 tons of clean coal per day. Of this 6,800 tons, 71 % is mined with continuous miners, the remaining 29% coming from one longwall unit located in No. 3 Mine. Our first longwall panel was started in November, 1961. In October, 1966, we started mining our seventh panel. The present panel is located in the Upper Sunnyside Seam which averages five feet in thickness, but does get as low as 51 inches. The seam pitches 5.5% in this vicinity. The roof is generally good and is comprised of 10 inches of shale cap rocs overlain with sandy shale and sandstone. The floor is sandy shale and is quite undulating in nature. The present panel is 3,800 feet in length with a face of 670 feet. The major equipment employed on our longwall unit is a 125 H.F. Anderton Shearer-Loader, British Jeffrey Diamond armored conveyors and a Dowty self-advancing-roof support system. The Anderton Shearer in use on our longwall unit has a 60" diameter x 27" cutting drum. During the shearing cycle, it traverses the face at 20 feet per minute with a cutting rate of 7.5 tons/minute.

Jan 1, 1967

Lingering effects of the 1990 oil shock that included overbuilding and corporate and individual financial distress caused the Gross Domestic Product to fall slightly to $5.67 billion (US billion = l09). With 254 million people - 697,000 in mining and petroleum - the US has more than 100 million dwelling units and 190 million licensed motor vehicles. New private housing starts fell 15% to one million units. New car production fell 11 % to 5.4 million units. Truck and bus production fell 8% to 3.4 million units. The inflation rate was 3%, while the prime rate of interest was 8.5%. The Producer Price Index (1982 = 100) changed as follows: -fuels and related products and power down 1% to 8l, • metals and metal products down 2% to 120, • chemicals and allied products up 2% to 126, and • non-metallic mineral products up to 2% to 117. Energy Imports of crude and refined petroleum, costing $50 billion, fell 5% to 2.8 billion bbl. Domestic petroleum production rose 1% to 3.6 billion bbl. Petroleum supplied about 39% of US energy, natural gas 24% and coal 22%. The National Energy Strategy was announced in February 1991. Its purpose is to encourage domestic production of fossil fuels and nuclear and renewable energy and to stimulate efficiencies in use. Congress continued to debate the strategy and took no action. Coal production fell 3% to 902 Mt (994 million st). About 60% of that came from surface operations. Seventy-eight percent of the total was used to generate electricity and 3% was coked.

Jan 1, 1992

By J. Noll, J. A. Organiscak, A. B. Cecala

"In recent years, significant strides have been made to optimize the design of filtration and pressurization systems used on enclosed cabs of mobile mining equipment to reduce respirable dust and other contaminants and provide the best air quality to the equipment operators. This synergetic effort has involved original equipment manufacturers building mining equipment, manufacturers of heating, ventilation, and air conditioning systems for mobile equipment, filtration and pressurization system manufacturing companies, as well as the National Institute for Occupational Safety and Health, and other government organizations. Considering all the advances made in this area over the last decade, one aspect that NIOSH still needs to assess is the longevity of optimal cab performance with respect to the quality (filtering efficiency) of the filters used in filtration and pressurization systems. In today’s culture, most health and safety professionals automatically believe that HEPA quality filters need to be used to provide the greatest level of protection to workers. Researchers at the Office of Mine Safety and Health Research for NIOSH hypothesized that HEPA quality filters may not be optimal for the mining industry and speculated that MERV 16 rated filters would be more appropriate in most cases. In order to test this hypothesis, NIOSH performed a two-year study comparing both HEPA and MERV 16 quality filters on two pieces of underground limestone mining equipment, being a roof-bolter and face drill machine. Testing showed at the 95 pct. confidence level that there was no statistical difference between the two efficiency filters on both pieces of mining equipment. Since the MERV 16 rated filters were less restrictive and provided greater cab pressure, and since they did not have to be replaced as often as the HEPA quality filters, researchers concluded the MERV 16 filters were the optimal choice for both pieces of mining equipment in this case study comparative analysis. INTRODUCTION When most health and safety professionals today think about filtration efficiencies and their correlation with protecting workers’ health, the normal assumption is the higher the efficiency of a filter, the greater the protection afforded to the workers. The next logical step is to believe that HEPA filters deliver the greatest protection for workers because they provide the highest filtering efficiency. Obviously high-efficiency intake filters are a necessity for an effective cab filtration and pressurization system on mobile mining equipment, but what is the optimal filter efficiency rating for achieving high levels of cab protection factor performance over the service life of filters? To address this question, the National Institute for Occupational Safety and Health (NIOSH) has performed an in-depth laboratory research study over the years simultaneously with numerous field studies to retrofit used enclosed cabs on mobile mining equipment with newer and more effective filtration and pressurization systems."

Jan 1, 2016

By John S. Cummings

Although there are many geologic situations which might be discussed at a session such as this, as I considered the problem, it became apparent to me that I should discuss a situation which has been of concern to me, and should be of concern to the geologic community. As a result, the questions which I will pose, and the criticisms, have not been arrived at quickly or easily, but have accumulated through time, to the point where I feel discussion is necessary. Very briefly let me say that my criticism of geologic mapping, of conclusions reached, and objectives or lack of such, results from my association with many areas where such studies have been completed, and resultingly my inability to comprehend the system of evidence or logic which supports extensive age-formational designations. The heart of the problem is that many conclusions resulting in geologic designations are based on weak or non-existent evidence, and such should be catagorized as hypotheses. Although the geologic community as a group does not approve or disapprove of such designations, it is evident that many or most of such designations attain a "status", and arc accepted as more or less valid statements. As will be shown, the amount of specific lithologic data provided in some quadrangle mapping projects is exceedingly slim. However, of concern herein is that the type of information presented at any stage is sufficient to warrant conclusions drawn. To see the magnitude of the problem, it is probably necessary to review some basic fundamentals upon which our geologic systems are established. The United States Geological Survey has defined a "formation" as the broad unit of geologic mapping consisting of a large and persistent stratum of one kind of rock. Obviously such a designation allows that a formation could be considered "time variant" in a horizontal as well as in a vertical context. However, other definitions enable a formation to mean units

Jan 1, 1972

By Ping Zhang, Shahram Mozaffari, Andreas Ylmefors

The risk associated with mining induced seismicity and the related rock bursts has become one of the major threats to the safety and sustainability of mining at the Kiirunavaara mine. The causes of mining induced seismicity at the Kiirunavaara mine are very complex and have affected our understanding on the source mechanisms of seismicity and further the mitigation of the seismic risk. Detailed analysis of historical mining induced seismicity at the Kiirunavaara mine was conducted. The focus of this analysis was placed on the classification of large seismic events and the evaluation of the influential factors on the classified seismic events. 145 events with local magnitude larger than 1.5 that occurred between January 1, 2011 and March 31, 2021 were analyzed. For this analysis, seismic events located in the hanging wall were not included, as these have not been observed to cause large damages to the mine itself. It was found that the magnitude of the events had good correlation with the stress change in relation to the production location. The seismic events were classified as mining-front associated, ore-pass associated, mining-front and ore-pass associated and others, according to their hypocenter location. Most of the mining-front associated events, concentrated around the production levels and slightly above and below them, generally correlated with shear cracks, and most of them occurred when the ore flow between two production levels started. The numerical modelling showed that slip of the geological discontinuity, due to unclamping between hanging wall and footwall, could be the major causative mechanisms, which further supports this finding. The ore-pass associated events are located close to the ore passes. Large seismic events located between ore passes have the source mechanism of both fault-slip and non-shear, but events located at the outer side of ore passes were all fault-slip type. By checking with the ore pass scanning data, it was concluded that the most of the events located between ore passes could be pillar bursts. An elastic core concept has been then used to define a critical pillar width. The paper is not intended to be prescriptive but rather to initiate discussion of the possible classification of seismic events at the Kiirunavaara mine and to present new perspectives of the causes of the seismicity for improving the present seismic risk management.

Apr 26, 2022

By Frederick W. Bauer

The potential worldwide "market" for metallurgical bauxite is about 94 million MT. The high degree of concentration of the alumina sector, combined with the high percentage of long-term contractual relationships, results in a small spot market with an illdefined price structure. Further segmentation occurs based on bauxite quality and alumina plant design. The potential 'free" market is estimated to be about 18 million MT that represent the requirements of nonintegrated alumina producers. It, too, is covered almost entirely by multi-year supply contracts.

Jan 1, 1984

By David M. Parkes

The hydraulic movement of coal is here defined as the movement of all sizes of coal in pipes and open flumes, by gravity and against gravity. It is not restricted to coal which is in slurry form. In other words, it is not crushed to a size in the 8 to 20 mesh size range. The top size could be as high as 12 inches. The dewatering of coal which is transported hydraulically is carried out to restore the coal to a suitable form for further cleaning, or for transportation by other methods. The process involves complete separation of all the coal, wood and rock from the water so that the water can be recycled without undue damage to pumps, pipes and monitors.

Jan 1, 1976

By P. L. Webster, S. D. Thompson

Sevim and Wang (1988a) have presented a model for designing haulage systems in underground coal mines. The authors contend that their model uses a heuristic algorithm to optimize various haulage system parameters. In reality, it would be nearly impossible to optimize a haulage system, because mining plans are uncertain and often change with respect to time. Therefore, haulage system design poses both a stochastic and a dynamic design problem, and its optimization appears to be well beyond the scope of heuristic algorithms. In regard to the authors' design model and its practical significance, a number of additional issues warrant further discussion and clarification. These issues include: l) their model's alleged advantage over simulation models, 2) the correctness of their belt network design, 3) the correctness of their bunker design, 4) the necessity of their proposed bunker clearance policies, 5) the correctness of their shaft-bottom bin design, and 6) the

Jan 1, 1991

By Dave Willis

Two hundred and thirty million tons of coal! That is what the Burlington Northern (BN) railroad anticipates that it and the Chicago North Western railroad (CNW) will haul out of the southern Powder River Basin l (see map on page 966) in 1994. Put that 209 Mt (230 million st) into railroad perspective. Current average train size is 113 cars. With each car transporting 94 t (103.5 st) of coal, each train averages 10.6 kt (11,700 st) of coal. Simple division shows that 209 Mt (230 million st) of coal equals 19,658 trains a year. So BN and the CNW must move 54 loads a day out of the Basin. Every load, of course, has an empty side of its cycle. This means that 54 loads a day translates into 108 total trains a day, or 39,420 trains a year through the southern PRB.

Jan 1, 1994

By G. L. Barthauer

It is a distinct privilege to have the opportunity of addressing this group today. Although I, myself, am not a mining engineer, I have always had profound admiration and respect for those of you who each day live and work according to the tenets of Murphy's Law. Murphy, as some of you may know, was an Irish philosopher whose sole contribution to his field was the observation, "In the mining industry, if anything can possibly go wrong, it will!" You have heard this afternoon a variety of papers, touching on or describing in some detail imminent problems which presently face the coal industry. Many of these problems show no signs of diminishing. Actually, there is good reason to believe that they will intensify as governing bodies pass additional enabling legislation and regulatory agencies adopt more stringent "Rules and Regulations". In many cases, these groups are seemingly oblivious or indifferent to either cost factors or technical problems involved in achieving the desired goals.

Jan 1, 1967

By A. Bayer, T. Klopfer

"As a leading global strategy consultancy, Roland Berger Strategy Consultants firmly believe that the issue of sustainability is at the core of every business activity. Thus, strategies to enhance corporate sustainability (CS) are an essential cornerstone in the consultancy's approach to develop and implement new strategic concepts for the clients. In this paper, the authors conclude that innovation is the only solution possible to guarantee growth and welfare gains while achieving sustainable development. More efficient and effective ways are necessary to enable technical and social breakthroughs. To illustrate Roland Berger Strategy Consultants's vision on CS, four selected cases from the basic resources, energy and utilities sectors are presented. They demonstrate that the implementation of a CS strategy does not only refer to CEO spheres and are by no means just a moral justification for current business practices. Rather they show that the decision to opt for these new ways also opens up multiple opportunities."

Jan 1, 2005

By C. Pace, D. Darlington, A. Montera, C. Lingren

"A phosphate beneficiation plant in Utah is using isotope-based Prompt Gamma Neutron Activation Analysis (PGNAA) technology to analyze the entire slurry streams of the incoming feed and final product in order to adjust the flotation circuits in near real time and optimize the plant output. The plant has gained greatly improved visibility/control and has reduced product variability for improved profitability and product quality. This paper takes a look at the economics as well as application details and the difference this technology provides in a phosphate application. SIMPLOT PHOSPHATES INTRODUCTION Simplot’s Vernal, Utah Phosphate Mine and Mill are located in the northeast corner of the state in the Uinta Mountains along US Highway 191, eleven miles north of the town of Vernal. The phosphoric acid and fertilizer plant fed by the Vernal mine is located 94 miles Northeast of Simplot Phosphates in Rock Springs, WY.At the Vernal plant, loader and shovel mining to 85 Ton capacity trucks is done at an annual rate of 3.8 Million tons of ore. Run of mine ore is crushed in a mineral sizer to minus 14 inch diameter at the rate 11,500 tons a day and transported to the SAG Mill’s 130,000 ton surge stockpile by overland belt. ORE RESERVES The ore is a Phosphoria Formation of sedimentary rock type dating to the Permian Age. The ore body rests over a 25 mile area on Weber Sandstone from the Pennsylvania and Permian geologic period. Layers of Phosphate Rock can vary in thickness from 0.3 up to 2.1 feet, alternating with layers of Mudstone. The eastern edge of the ore’s body Panel “G” runs 16 feet deep with a feed grade of 21.5% P205 with lower MgO diluents of less than 2.79%."

Jan 1, 2016

By R. E. Pennington

My subject this morning is coal liquefaction technology. Actually, coal liquefaction involves a number of technologies in a very complex system. The first slide shows the major components of such a system with arrows to indicate appropriate flows. The components are the facilities for coal feed preparation and handling; the coal hydrogenation or base liquefaction section; facilities for product separation and recovery, and in addition, facilities for the production of hydrogen from coal-based sources. A very rough break- out of the investments involved in these areas is given at the bottom of the slide. Investment is spread about equally among the three areas of operations Another way of looking at it is that the investments in what might be called support facilities are of the same magnitude as the base investment in the hydrogen facilities. Therefore, it is appropriate in a discussion of coal liquefaction technology to treat it as a system composed of a number of technologies. The next slide lists the various functions in the feed preparation section along with an indication of technology status. Storage, crushing, grinding, drying of coal all have been in commercial practice for a number of years. The slurrying and pumping of coal at least in water slurries, is practiced commercially also. The heating of coal slurries in oil to high temperatures under pressure is not in commercial practice and development and testing is going on by a number of people in this area. Some rather complex phenomena occur when coal oil slurries are heated to high temperatures.

Jan 1, 1975

By D. P. Caplice

On behalf of the Ontario Water Resources Commission, I would like to express my sincere appreciation to your Institute for presenting us with this opportunity to outline the regulatory control programme as it relates to the mining industry in the Province of Ontario. In Canada, and particularly in Ontario, we are blessed with an abundance of natural resources. Fresh water in the form of lakes and rivers covers nearly 17 per cent of the area of the Province. (Total area of the Province of Ontario is 412,582 square miles.) The mining industry, which had its beginning in the early 1800's with a small iron ore plant, has progressed with the major discoveries of nickel and copper in 1883, silver in 1903, gold in 1908, iron in 1939 and uranium in 1953, to the point where, in 1966, almost one billion dollars in mineral wealth was mined in Ontario. Water, in spite of its great abundance and with due respects that it may become a natural resource worthy of export in the foreseeable future, has become increasingly precious in Ontario, particularly in the more urban areas in the southern part of the Province.

Jan 1, 1968

By L. Yan, T. Lutz, J. Noll

"Mine disasters, such as fires and explosions, can create a hazardous atmosphere due to the generation of carbon monoxide (CO). After a mine disaster, contaminated mine air can enter the refuge alternative (RA) as miners enter. Most built-in-place (BIP) RAs use an air delivery system to provide an unlimited supply of breathable air through a borehole which also serves to purge contaminants. In order to determine what levels of contaminants enter the RA, researchers from the National Institute for Occupational Safety and Health (NIOSH) conducted testing in NIOSH’s Pittsburgh Experimental Mine using groups of 5, 15, and 30 subjects entering the RA. The experiment used sulfur hexafluoride (SF6) as a tracer gas that was released into the air outside of the BIP RA to establish a uniform concentration. After the human subjects entered the BIP RA, the SF6 levels inside the RA were measured to quantify how much of the tracer gas entered the BIP RA. In tests conducted while the borehole air supply was left off as test subjects entered, interior contaminant levels were less than 3% of the exterior concentration. In tests conducted with the borehole air supply activated as test subjects entered, the interior contaminant levels were measured at less than 2% of the exterior concentration. Considering a mine disaster can result in 10,000 ppm of CO in the mine atmosphere, these percentages indicate that unhealthy CO concentrations that may lead to headaches, dizziness, and loss of judgement can occur in a BIP RA. This information will help mines make decisions concerning air locks, air delivery systems and a determination if purging mechanisms are necessary. INTRODUCTION The Mine Improvement and New Emergency Response Act of 2006 (MINER Act) was enacted in the wake of three mine explosions/fires that claimed 19 lives that year. Intended to help improve underground coal mine accident preparedness, the MINER Act includes provisions that target mine safety issues in areas such as emergency response planning, adoption of new technology, training and education, and enforcement of mine safety standards (MSHA, 2006). Section 13 of the MINER Act specifically directs the National Institute for Occupational Safety and Health (NIOSH) to provide for research into the effectiveness and viability of RAs for underground coal mines. This mandate culminated in the 2009 adoption of changes to the 30 CFR mining health and safety regulations, requiring underground coal mines to provide RAs capable of maintaining a life-sustaining environment for persons trapped underground. Such RAs can be either pre-fabricated or BIP shelters. The regulatory changes also include provisions establishing requirements for Mine Safety and Health Administration (MSHA) approval of RAs and their components, and among these provisions are numerous criteria for providing a safe, breathable atmosphere within RAs."

Jan 1, 2018

By Nes?e Çelebi

It has never been easy to finance within mining sector. Leasing may be an alternative source of finance for mining investments. Leasing is acquiring the right of usage for an asset for a definite period of time without having the ownership of it. In this study, a model for analyzing the lease financing opportunities for mining investments under risk and suitable for establishing a satisfactory leasing policy for both lessee and lessor is developed. Using the model, it is possible to obtain an expected equilibrium lease amount acceptable by both lessor and lessee and also the expected range of the equilibrium lease amount as a decision tool. First the existing leasing policies are mentioned, then the developed model is described. A case study is presented to illustrate the use of the model in establishing a leasing policy. In conclusion, the usefulness of the model is discussed.

Jan 1, 1992

By R. H. Mozley

It is not my intention in this paper to review recent developments in the mineral processing industry which might fall under the above heading, but to refer to some of the research that I have done over the past 25 years or so. To begin with then, my student days at the Camborne School of Mines, the year 1952. Equipment from the last century was still in everyday use at the local tin mines. At South Crofty Ltd a steam beam engine 100 years old was pumping mine water from 2000 feet, the motive force being conveyed from surface to the pump at the bottom of the mine by a 14 inch square pitch pine rod joined with forged iron straps, steam winders were still in use, and in the mills, stamps ground the ore, and the cassiterite was recovered by equipment with exotic names like "buddies, kievs, and round frames." And to equip us students for the brave new world, we included in our practical mineral dressing a day's test programme with a Californian stamp -- experience that I am still waiting to put to good use!

Jan 1, 1984