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By W. G. Miller

A series of computer programs for the analysis and mapping of coal-related data has been developed at the Illinois State Geological Survey; these programs, known collectively as the Coal Data System, represent the latest achievements in computer processing of geologic data at the Survey. Building upon programs previously developed in the Survey's Computer Services Unit, they expand the scope of the computerized data base that the Survey has been using for analyzing coal-related data. The System was partially developed during a joint study by the Illinois State Water Survey and the Geological Survey entitled, ?Coal and Water Resources for Coal Conversion in Illinois.? 2 In that study the available coal reserves more than 42 inches thick in the two principal coal seams throughout the state were mapped. The System was used to calculate the coal reserves and to report the average number of tons of coal in place per square mile in each township (Figures 1 and 2). It also produced maps of the coal features of sufficient quality to be printed on material that was scribed as master copy for the printing of full-color 1:500,000 scale maps (see Figures 3 and 4).

Jan 1, 1975

By Kent E. McElhattan

The selection of efficiency machinery for an underground mining system is a highly skilled art. Modern techniques of mining, based on sound engineering principles, increase the probability of success. These techniques alone, however, will not guarantee maximum productivity. Human judgement, based on experience with mineral seams and geological conditions, remains the single most important input of the decision-making techniques in selecting high production equipment. The myth of a "Scientific Selection Factor" is absurd. The belief that such a factor exists can waste the time and resources of mining management. Until now, mineral extraction from the original desposit has defied all attempts to systematize the knowledge. Computerized programs are excellent for solving underground transportation and ventilation problems. The variables can be defined by mathe¬matical techniques in this type of problem. By the same, token, "Trial and Error" is not an acceptable method in today's technology-minded world. The candid truth of the matter is that practically nothing is known of the phenomenon of extracting a mineral from the solid. Likewise, local conditions make it nearly impossible to predict accurately the reaction of surrounding strata after the mineral has been removed. The unpredictability of the environment resulting from extracting minerals underground will remain a challenge to mining engineers for many years. In fact, we are barely beyond the trial and error stage at this point in time.

Jan 1, 1969

By H. C. Siebert

According to the "Survey of Energy Resources 1980" (1)*, which was prepared by the Federal Institute for Geosciences and Raw Materials in Hannover (FRG)for the World Energy Conference 1980 in Munich, the world coal deposits are assessed at 775 billion tce proven reserves 448 billion tce of them recoverable and 6 161 billion tce additional resources. If one ignores growth rates, the current world coal output of 2,8 billion tpy gives our recoverable reserves a static life expectancy of 175 years. With an average increase in world output of 3,2 % like between 1973 and 1980 this range would be further shortened to an alarming degree. Furthermore, the criteria used to distinguish between workable and unworkable resources give rise to the suspicion that deposit characteristics are not always taken into account to a sufficient degree. For example, little attention is paid to major ?Bonitaet" - factors such as dip and seam thickness. There have been wide-ranging scientific discussions on the lower limit for workable coal resources, but no such limits have been set at the other end of the scale. Otherwise it is well known that performance and costs are badly affected den in level and moderately inclined seams the seam thickness is more than 4 to 5 m, because special mining methods have to be used beyond this limit. These are associated with significantly higher costs than with the winning of seams of ?normal? thickness.

Jan 1, 1985

By Robert B. Crookston

Oil from shale has been produced in foreign countries for more than a hundred years; however, except for short-lived, small operations, no commercial quantity of oil shale has yet been produced in the United States. Efforts to develop a viable oil shale process have been underway domestically for many years. At the present time, with the need for energy so urgently upon us, almost a dozen development ventures are underway or planned in Colorado and Utah. Of these several ventures, only Colony Development Operation has completed the development, testing and design of a ready-to-go 50,000 barrel per day com¬mercial project. Colony is a joint venture of the Atlantic Richfield Company, Ashland Oil Company, Shell Oil Company and The Oil Shale Corporation, more commonly known as TOSCO. TOSCO is the exclusive licensor of the TOSCO II retorting process and other oil shale technology, which includes mining, crushing and spent shale disposal techniques. This paper will deal, however, with only the materials handling aspects of the commercial oil shale operation. Oil shale handling for this infant industry is unique in that an understanding of the physical characteristics of the ore and the demands on material handling to the plant must he understood. Colony Development has completed ten years in the research and development of techniques and processes for mining, crushing and retorting raw oil shale and the disposal of spent or processed shale. A great deal has been learned about oil shale, in many cases confirming our intuitive analyses and the work of others, but more specifically we have brought it all together to a point where equipment performance and the specifications have been established and a design for the first commercial plant is now mature.

Jan 1, 1975

By P. Soros

Rich iron ore deposits were discovered during the 1960's in the mountain range of Serra dos Carajas, State of Para, Brazil, near the headwaters of the Tocantins River some 400 miles southwest from the state capital of Belem. (See Fig. 1 and 2). The key to the successful exploitation of this deposit was the development of an efficient an economical transportation system. The rugged terrain, and the dense tropical vegetation of the Amazonian jungle and the irregular coastline with its high tidal range presented severe obstacles to the planning and building of such system. Starting in 1972 extensive surveys and studies were carried out by Soros Associates on behalf of CVRD to determine the optimum way of transporting the ore from the mine site to the markets, most of which are located overseas. Overland transportation to the coast, loading into seagoing vessels and the ocean voyage to the ports of destination was treated as an integrated system in these studies.

Jan 1, 1986

By M. Zaske, E. R. Mortensen

"As mine operators continuously look for ways to improve functionality and increase the capacity of their facilities, existing process equipment is often pushed to and past its designed limitations. As a result, equipment manufacturers are asked for economical solutions to meet redefined processing needs. Newmont Mining in Nevada was faced with such a need in its carbon-in-leach (CIL) train. In a collaborative effort between Newmont and Derrick Corp., tests were conceived to assess the viability of drop-in replacement screens using a three-dimensional screen panel. The synthetic pyramid screen panel was designed to increase flux while maintaining the existing equipment footprint. The test is the end result of an ongoing research and development project that Derrick undertook in an effort to refine and upgrade its urethane screening media. The application of this new screening media is presented for this CIL application along with future plans to implement the technology in trash, safety, carbon dewatering, carbon sizing and other scalping applications.In spring 2014, Process Machinery Associates (PMA), Derrick’s local area representative, met with Newmont to discuss the operation of the in tank screens in the CIL train at Twin Creeks, near Golconda, NV. The process was originally designed for about 12+ kt/d (13,000+ stpd) but the throughput has been steadily rising since the plant was commissioned. Newmont now requires 14.5 kt/d (16,000 stpd) to be processed. The original screens were running at their maximum capacity, and Newmont required additional screening capacity to continue the upward trend in production.Physical separation by use of screening is one of mineral processing’s oldest methods. Screening media can be prone to blinding and pegging, and the necessary support structures required for finer apertures result in smaller open areas. Therefore, more screening area generally requires larger panels and, thus, larger machines, screening media that does not blind or a combination of both.In an effort to avoid larger machines, Derrick had been working on a revolutionary threedimensional panel that would add nonblinding screen area in the same footprint of an existing machine. Alpha testing of the new screen panels began at Newmont Mill 2/5 in July of 2013. It was still occurring when PMA approached Twin Creeks about beta testing a refined machine and pyramid panel. After presenting the initial results, Twin Creeks determined that an upgraded machine and pyramid panels would be a possible solution to meet production needs. The testing of a machine eliminated the risk of capital costs to Newmont and provided Derrick the opportunity to obtain additional data."

Jan 1, 2015

By C. D. Litton, I. E. Perera

This report presents the results of experiments to evaluate different types of mine fire sensors in an underground mine environment using a commercially available atmospheric monitoring system. To determine how well carbon monoxide (CO) and smoke sensors respond for purposes of fire detection, experiments were conducted using test fires of different mine combustibles and for both flaming and nonflaming combustion. The experiments were designed to assess the response of fire sensors to different contaminants and different contaminant levels produced from the test fires. The experiments were performed in the Safety Research Coal Mine at the U.S. National Institute for Occupational Safety and Health’s Bruceton Research Facility in the presence of an average ventilating air velocity of 1.6 m/s (315 fpm). Five fire sensor stations were located downstream of the test fire at fixed locations, with each sensor station consisting of four sensors: a CO fire sensor and three different smoke sensors, of which two were evaluated by the Mine Safety and Health Administration (MSHA) for intrinsic safety and the third was used extensively in underground mines overseas but not evaluated by MSHA for intrinsic safety. All four sensors were mounted near the center of the entry and in the upper onethird of the entry height. A UL-listed combination ionization and photoelectric smoke sensor was mounted near the roof at the first sensor station and its responses were compared against the responses of the four CO and smoke fire sensors. Sensor response data, contaminant travel times, and the impact of fire on the existing ventilation flow are discussed as they apply to earlywarning fire detection. Of significance in the analysis is the need for performance standards for mine fire sensors in order to provide for consistent and timely early warning of developing fires.

Jan 1, 2014

By I. Papadopoulos

Nowadays, geophysical prospecting is implemented in order to resolve a diversity of geological, hydrogeological and geotechnical problems. Though plenty of applications and a lot of research have been conducted in the country-side, only a few have been reported in the literature concerning urban areas, mainly due to high levels of noise present that aggravate most of the geophysical methods (e.g. electromagnetic, seismic, gravity etc.) or due to spatial limitations that hinder normal method implementation (e.g. electrical). Among all geophysical methods, electrical tomography proves to be the most rapid and urban noise insusceptible technique. This work presents a case study in the urban area of Hania (Crete I., Greece), where Electrical Resistivity Tomographies (ERTs) have been carried out for the detection and identification of possible buried ancient ruins or other manmade structures, prior the foundation of a building. Nineteen profiles were surveyed in a 20x40m grid using dipole-dipole configuration. The results indicate two areas of interest, that are interpreted as probable old wells, in the context of the existence, in former times and in the same area, of an olive oil plant. In the vicinity, near surface ancient ruins have been disclosed, but no such evidence provided this survey, for the particular area under study and the prospected depth. The collected ERT-data were processed by applying advanced algorithms in order to obtain a 3D-model of the study area that depicts more clearly and accurately the interesting subsurface structures.

Jan 1, 2005

By K. Chief

American Indian lands contain a vast amount of renewable and non-renewable resources that have consequently been mined (Smith and Frehner). Therefore, it is understandable that tribes are concerned about environmental impacts from mining and their ability to minimize and mitigate these impacts. This has created a need to better understand mining and its environmental impacts. The University of Arizona Superfund Research Program Mining educational modules developed educational modules for tribal colleges focusing on environmental impacts of mining, remediation of mining wastes, and sociocultural impacts of mining. Educational modules are independently packaged units of study designed to enhance the learning process and can be modified and adapted to different learning scenarios and objectives. In addition to providing specialized knowledge, the modules feature hands-on activities, incorporation of technology, student involvement, discussion, and exchange of ideas. Modules will aim incorporate traditional ecological knowledge and approaches that promote effective science learning for native students. Modules are designed to augment existing associates of science programs (e.g. biology, chemistry) currently offered at tribal colleges and can be modified for use in K-12 education and for non-tribal audiences.

Feb 23, 2014

By J. L. Hoover, P. W. Conrad, J. Downey, S. Parrow, S. Rosenthal

The goal of the drill bit consumption study was to develop an equation(s) based on various components that affect drill bit wear and use that equation(s) to estimate the consumption of bits during production drilling. Drill bit data from various geographic locations were compiled and used to develop linear regression equations using the Microsoft Excel software package. Multiple drill bit consumption equations were developed and statistical analysis was used to verify the accuracy of those equations. The equations will allow mining companies to more accurately forecast drill bit consumption when evaluating new mine properties. This capability becomes increasingly beneficial to forecasting as the cost of consumables increases.

Jan 1, 2012

By O. P. Sinha, Biswajit Mishra, A. K. Mandal, Raj Kumar Dishwar, G. S. Mahobia, Ram ji Omar

Most of the mineral deposits found in North-East India remain unexploited due to inadequate knowledge on their status, economic viability, and requisite mining technologies. The aimof this study is to characterize the multimetallic magnetite mineral deposit from the Nagaland area in India. The quality of iron ore was evaluated to establish its suitability as a raw material for iron production. Detailed studies were conducted to establish the composition and properties of the samples. X-ray diffraction (XRD), X-ray fluorescence (XRF), electron probe micro-analyzer (EPMA), and petrographic microscopy techniques were employed in the investigation. Shatter and tumbler test was performed for analyzing the mechanical properties of the ore. XRD studies indicated that magnetite is the major mineral with low amounts of martite, maghemite, and quartz. XRF/EPMA results indicated that magnetite contains 35–65 wt.% of iron and 1–5 wt.% of chromium. It also confirms the presence of Ni and Al up to 1 wt.% and Si up to 6 wt.%. Chromite-rich ore contains up to 30 wt.% Cr and 15–20 wt.% of Fe.

May 10, 2021

By R. L. Kloberdanz

Peruvian legislation requires the preparation of an Environmental Impact Study (EIS) for new and expanding mines/beneficiation facilities and the preparation and implementation of an Environmental Adjustment and Management Program (PAMA) to control and mitigate environmental impacts associated with existing mining/beneficiation activities. Shepherd Miller, Inc., developed guidance documents for preparing an EIS and PAMA for Peru's Ministry of Energy and Mines and presented workshops to Peru's mining industry on preparing an EIS and PAMA. This paper discusses the process and approach taken and the results.

Jan 1, 1998

By A. Kosiór

Many remnants of gold exploitation in the Middle Ages were found in the Lower Silesia region. The oldest evidence of such activity was found in the neighborhood of Zloty Stok and comes from the 7th century. Mining of precious and non-precious metal ores has a great relevance in the late Middle Ages when advanced metallurgic technologies were mastered, that allowed to obtain gold, silver, lead, copper, zinc and arsenic from complex ores occurring in the oldest middle part of Sudetes. Historically it concerned the area of the Swidnica Principality and Klodzko County. Experience obtained in Freiberg, which is located close to the Lower Silesia, was used in the development of mining. A high level of mining and metallurgic technology was obtained in the 15th century that caused significant increase of production of the metals mentioned above. Unfortunately, the good time of Lower Silesian mining lasted only up to the 18th century; the notion of preservation of cultural heritage was unknown at that time. The Lower Silesian medieval mines were not in such a fortunate situation as the ?Wieliczka? and ?Bochnia? mines, which are operating to present-day, and which made preservation of the most interesting headings and objects possible. All these objects are now available for visitors. However, in the case of the middle Sudetes it seems that it is often sufficient to localize old shafts and headings on the basis of careful observations and old maps and carry out some earthwork to uncover medieval headings and objects of underground mining activity. They are often preserved in amazingly good state; this also pertains to mining devices. Another issue is of course the permanent preservation of that heritage and its possible availability for re-searchers and tourists. Some success has been achieved in that field (Zloty Stok Gold Mine is a good example), but also problems were encountered in many cases. The Lower Silesian Coal Basin, which has not been exploited for 10 years is an evidence that there is not a holistic conception of mining heritage renovation. Many attractive mining objects disappeared irrecoverably from the mountainous landscape of the Middle Sudetes despite common consciousness of their significance for cultural development of Silesia and other regions.

Jan 1, 2006

By Z. Henderson, J. R. Saylor, L. Rojas-Mendoza

"Diesel particulate matter (DPM) is a major occupational health hazard in underground mine environments, even with available abatement technologies. Prior work has demonstrated that micrometer-scale water droplets, or “fog,” may be effective in removing significant number fractions of DPM from a conditioned exhaust stream. Here, a series of laboratory experiments are described which demonstrate that such a treatment can remove significant DPM mass from an unconditioned stream. The removal mechanism involved coagulation of the DPM and drops. The fog treatment removed about 45 percent more DPM mass on average than no treatment. Varying engine load, flow rate and fog droplet number density did not significantly affect the results under the range of conditions tested. IntroductionDiesel engines have seen widespread use for well over a century due to their relatively high thermal efficiency and fuel economy (Heywood, 1988). Recently, however, the adverse health risks of diesel exhaust have become increasingly clear. The term diesel particulate matter (DPM) is used to refer to the solid components of diesel exhaust, which are an ultrafine mixture of elemental and organic carbon (EC and OC) and minor constituents including sulfates and metal ash (Kittelson, 1997). DPM is generally considered to occur almost entirely in the submicrometer range. It is classified as a carcinogen (Occupational Safety and Health Administration, 2013), and epidemiological studies have demonstrated a positive correlation between long-term exposure to DPM and other combustionrelated fine particulates and increased cardiovascular and pulmonary diseases (Pope et al., 2002; McDonald et al., 2011). Many of the risks of diesel exhaust are associated with the physical and chemical properties of exhaust components (Heywood, 1988; El-Shobokshy, 1994; Kittelson, 1997). Exposures are generally measured and regulated on the basis of mass concentration. However, DPM number density and particle size are increasingly recognized as critical factors in terms of health outcomes (Bugarski et al., 2012; Kittelson, 1997; Occupational Safety and Health Administration, 2013; Pope et al., 2002)."

Jan 11, 2017

By C. C. Clark, D. J. Benton, J. B. Seymour, L. A. Martin

"The U.S. National Institute for Occupational Safety and Health (NIOSH) is conducting research on jackleg use and related accidents in underground metal mines. This paper provides an analysis and overview of jackleg drill usage, accidents, operational characteristics and alternatives, based on information from injury reports, legacy research, stakeholder input and published literature. The results indicate that jackleg drills are involved in more groundfall accidents in underground metal mines than any other drill, and jackleg-drill-related injuries are most prevalent at the face in the course of installing initial ground support. Practical mechanized alternatives to jackleg drills for drilling and bolting under incomplete support in narrow underground openings have not yet been realized. Small, versatile mechanized bolting equipment needs to be developed to address jackleg-drill-related accidents and improve safety at mines where jackleg drills are being used. IntroductionJackleg drill is a generic name for a handheld, rotary, percussion rock drill equipped with an attached reaction leg to provide stability and thrust (Fig. 1). All of the drill and leg controls are located near the operator’s handle at the rear of the head portion of the drill. Jackleg drills are classified according to the bore size of their pneumatic pistons, which normally range from 6.03 to 8.26 cm (2.375 to 3.25 in.) (Kurt, 1982; Clark, 2012). Jackleg drills typically weigh 46.7 kg (103 lb), but the weight can approach 54.4 kg (120 lb) after being fitted for operation with drill steel and air and water hoses (McKibbin and Clark, 2001). In underground mines, jackleg drills are commonly used to drill 3.8-cm (1.5-in.) diameter holes up to 1.83 m (6 ft) deep in rock."

Aug 1, 2016

By B. R. Waples

The first reaction in organizing a project of magnitude is that it's the same as smaller projects -- just bigger. This is not totally correct. The industry's record of completing big-money jobs on time and within budget is not outstanding. From a personal point of view, my question is: What is the project size at which controls are lost? Is it controls? Is it the number of pieces of equipment? Is it the number of decisions to be made? The slowness of communications? Or is it a combination of all of these? In working on multimillion-dollar jobs, the percentage of overrun seems to be lower or show an underrun when the following basics are followed: 1) Preplanning is intensified 2) Data gathering is complete 3) Approach is optimized 4) Planning is realistically scheduled 5) Changes are minimized 6) Decisions are expedited

Jan 1, 1982

By Ross W. Whipple

Applying geophysical techniques in potential geothermal areas has received: little attention in the United States, though it is widely used and accepted in New Zealand and Italy. In those countries it has been demonstrated that geophysical surveys can be useful in locating new geothermal areas and in directing test drilling programs. Geophysical studies in a thermal region can provide structural information and, if conditions are right directly; locate subsurface hot waters. They can give indications of sub-alluvial rock types and of the thickness of alluvial cover. In certain cases they can be used to estimate the power potential of a hydrothermal system.

Jan 1, 1963

By Jan M. Mutmansky

Since 1973 when the first edition of the SME Mining Engineering Handbook was published, many significant changes have occurred in the US mining industry. The industry went through a fairly prosperous period immediately after 1973, but then many economic pressures came to bear on mining companies, particularly in the metal and coal branches of the industry. These pressures changed both the mining methods used and the general economics of the mining methods. As a result, the industry today is different in many ways titan it was in 1973. A general summary of some of the more important changes that have come about will be provided here as well as some assessment of the effects of these changes on the choices of mining methods. In the metal mining industry, the most significant trends were increased surface mining, the use of larger and more efficient equipment, and increased technology and automation. The primary impetus for these changes was unprecedented competition from foreign producers. In many cases, this competition came about because of the nationalization of foreign mines and the tendency for these mines to become a source of foreign exchange. Under these circumstances, the mines could be operated even though they were not profitable. As a result, domestic

Jan 1, 2008

By D. Shink

A small scale continuous flotation cell was designed and constructed at Noranda Technology Centre to develop a mobile testing flotation circuit located next to the production circuit. This mobile small scale flotation pilot plant can easily and economically be set up at any circuit in a mill and used to evaluate and predict plant performance against a given flotation condition. The main feature of the cell, beside the provisions of automatic pulp level and feed rate control, is to provide a reduced surface to volume ratio approaching to that of an industrial machine. This paper describes the basic design and the results of various testwork carried out to date including aeration, conditioning, reagents, recirculation, flotation gas, etc. are presented in comparison with the plant production results.

Jan 1, 1992

By M. K. Larson, J. K. Whyatt

Proper employment of numerical stress analysis design tools is based on the demonstrated ability of a model to capture key elements of the geologic site model and accurately simulate how these elements interact with a mine design. While these tools have progressed markedly, they are, at heart, a gross simplification of the abundant complexity of a natural setting and its response to mining. A generic deep longwall site model was developed that includes aspects of the geology of deep coal mines in the Wasatch Plateau and Book Cliffs coal fields of Utah. The site model contains a set of common features and observations of how these features typically respond to mining. This site model was the basis for evaluating use of empirical, boundary element and volume element stress analysis tools to analyze the distribution of stress around a deep longwall panel. More specifically, this evaluation examined shifting of stress to panel abutments and gob, distribution of stress in the abutment and deformation and failure of bridging strata. Measurements of abutment stress changes at two sites in the Wasatch Plateau region were used to illustrate model calibration. Overall, these comparisons highlight the considerable differences between methods. Volume element tools can incorporate considerable detail and have fewer underlying assumptions, but this detail carries a considerable computational cost. Boundary element tools are much more efficient. However, this efficiency comes at the cost of added assumptions. These assumptions were challenged by the presence of a strong sandstone unit in the overburden, leading to boundary element results that depart significantly from volume element results. Empirical rules are the simplest, but are even more burdened by assumptions, many of which are implicit in underlying cases. Insight into the nature and impact of underlying assumptions in each method is essential to the proper use of results in mine design.

Jan 1, 2009