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By W. J. Kogelmann

Roadheaders, also called Boom Miners or Boom-type Tunneling Machines have been in North America since 1968, when first introduced by Willy Kogelmann, the founder of Alpine Equipment Corp. (?Alpine?). Roadheaders were invented in Europe in the late 1940s. Machines with in-line, axial cutter heads were developed in the former Soviet Union. The British Dosco DRCL is based on the Russian PK-3 roadheader. Roadheaders with transverse ?ripper? cutter heads were invented in Hungary (1). The Austrian-made Alpine Miners of VOEST-Alpine, purchased by Sandvik AB, are based on a 1965 Hungarian license. Roadheaders are widely used in the mining and tunneling industries because they can excavate drifts, entries and tunnels with cross sections of any shape and size, can handle mixed faces, work on steep grades, and negotiate tight curves and cross-cuts. A roadheader?s only major limitation is the strength and abrasiveness of rock and minerals to be excavated. This paper covers roadheader selection criteria, improvements in reliability, attachments for flexibility (Multi-Tool Miner), and automated support systems for increased cutting time for increased shift production.

Jan 1, 2008

By John M. Arnold

Several years ago it became apparent to some of our people that; there was developing a very definite need for largee coal reserves in the West to satisfy- the need for fuel for the furnaces of electric generating plants with the rapid development of, the West, of both population and industry, it was impossible for hydro-electrics plants to keep up with the ever increasing demand for electricity. In 1960, Mr. E. R. Phelps, then associated with the engineering department of Peabody Coal Company, began a search for and development of coal deposits in the very remote northeast section of Arizona near the village of Kayenta. Travel to this section of the country was not easy even at this late date, and it was an eight hour drive from Farmington, New Mexico to Kayenta, Arizona, a distance of some 130 miles. The trip was over roads that even' a-horse and wagon had trouble negotiating and a four wheel drive vehicle was about the only type of transportation that could satisfactorily traverse these roads, as testify many badly beaten sedans and coupes that tried it. Since that time a very excellent road has been constructed from Shiprock; New Mexico to Cameron, Arizona where it junctions with another excellent road that runs north to Page, Arizona and the Lake. Powell area and south to Flagstaff, Arizona on highway 66. Kayenta is a small village nestled at the foot of the Black Mesa near its northeast extremities. The coal deposits of interest were on the surface of the mesa. This location presented another problem, as the only trail to the top of the mesa was intended for walking, horseback, or a brave soul In a horse and wagon. Once again the four wheel drive vehicle was about the only answer. To reach the coal deposits you must climb the mesa, which is vertical ascent of some 1,500 feet, and then proceed southward into the bowl of the mesa with an ensuing descent of some 1,000 feet, finally coming to an elevation of 6,500 feet, at which elevation the coal outcrops become apparent.

Jan 1, 1969

By Sadegh Elyasi

TBMand roadheader are two dominating excavation machines in underground tunnelling projects. The performance of these two tunnelling machines has been reviewed and analysed individually by many researchers from multiple points of view. However, there are almost no studies that have made an extensive comparison between these two machines, mostly from financial points of view. The current study is intended to characterize both financial and technical status of these two mechanical tunnelling machines in one of the biggest coal mines in Iran. The main objective of this study is to define the best method and equipment that meets a predefined economic goal, which is mainly to maximize the net present value. To this end, a technical and financial model based on the geomechanical and financial parameters involved in the project has been prepared and the financial part of the project has been carried out by applying COMFAR III financial analysis software. Subsequently, a sensitivity analysis of the model was conducted in order to evaluate the effect of involved parameters on the project. According to the results, a roadheader has better economic justification than a TBM, while the TBM has a better advance rate than the roadheader.

Feb 12, 2021

A viable mineral economy requires availability of economic deposits, the ability to exploit then, and protection of the public interests. The natural tendency for each party to consider only its legitimate self interests can lead to delays or deadlocks. The paper presents several viewpoints aimed at opening each party's mind to the ideas of others in the hope that negotiations might be more reasonable and rapid for the benefit of all concerned.

Jan 1, 1979

By Adrian C. Dorenfeld

Concentradora "Dana Aida" (100 t/d capacity) was built in 1971-1972 to treat dumps and ores containing mixed oxide-sulfide copper-gold-silver minerals from two veins. The veins, Don Felipe and aria are about 150 m apart, but are distinctly different mineralogically. The deposit is near San Juan de Guadalupe, Durango. Mexico. All new process equipment was manufactured locally, in or near Torreon, Coahuila. Sampling, ore testing, flowsheet design, plant design, drawings purchasing, financing, etc. was planned and directed by two engineers. Construction was executed by local miners and common labor (largely agricultural). The paper presents detailed costs for equipment and construction. The subsequent breaking-in operation is discussed.

Jan 1, 1979

By Stanley N. Watowich

Recently the petroleum market has made us aware that we are indeed global natural resource consumers, and as such, we have become captive to fundamental global resource economics and their attendant vagaries. Global resource supply problems are as old as civilization and mineral exploration one of its important catalysts. On the basis of natural resources empires have been expanded and new frontiers have been developed. Global consumption and production might even be viewed idealistically as a system dedicated to optimizing distribution to the consumer. However, this is not the case. Political instability and increased government polarization make dependency on a global market somewhat insecure. The U.S. must evaluate its domestic mineral re- sources on the basis that all metals are critical and that dependency on even the common and base metals may ultimately weaken our domestic economy and our potential international relationships and could cause critical weaknesses as demonstrated by the petroleum problem. This paper evaluates specifically the Duluth Gabbro Complex, of Northeastern Minnesota, (figure l), as a potential resource of critical and strategic metals. First, a chronology of some of the early exploration, will be followed by more recent intensive company studies and preliminary evaluations of economic feasibility. Lastly, metallurgical data, on some optimum conceptual mining plans will allow metal production data to be compared with an estimate of U.S. domestic needs in 1990. The purpose of this paper is to put into focus the difficulty of converting resources into vitally needed reserves.

Jan 1, 1981

By Xiyu Gao, Yi Yang, Mark I. Pownceby, Shuiping Zhong, Miao Chen

In the present study, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray absorption near edge structure (XANES) spectroscopy, and Raman spectroscopy were used to investigate the effect of chloride ions on chalcopyrite bioleaching and chemical leaching at 25 °C. The leaching results show that the addition of chloride ions suppressed the dissolution of chalcopyrite in both chemical and bacterial leaching. In chemical leaching, the solution redox potential in the experiment without Cl− stayed in a range more suitable for chalcopyrite dissolution compared with experiments with Cl− . In bioleaching, the bacteria activity was suppressed by Cl− leading to low dissolution rates of Cu. Surface morphology and chemical speciation studies confirmed the formation of potassium jarosite on the surface of the chalcopyrite leach residues. In addition, S K-edge XANES indicated the formation of trace amount of elemental sulfur and covellite on the mineral surfaces.

By John W. Sweeney

Florida is usually thought of as a vacation State, not a mining State, yet Florida has been the leading producer of phosphate rock in the United States for 85 consecutive years and in 1978 supplied over 80 percent of the national output and over 30 percent of the world's output. It is estimated that the Central and South Florida phosphates contain 412,800 short tons (374,000 metric tons) of U308, that 115,000 short tons (104,000 metric tons) of U308 will be contained in the wet-process phosphoric" acid procsssed in the United States through the year 2000, and that 54,000 short tons (49,000 metric tons) of U308 will be available from Florida. In 1978, two companies in Florida and one in Louisiana went on-stream recovering uranium oxide from wet-process phosphoric acid and three others started construction of U308 extraction facilities. These six companies will have the capacity to recover 2,137 short tons (1,900 metric tons) of U308 annually in 1980, which will account for about 15 percent of our domestic requirements.

Jan 1, 1979

By W. H. Renison

This paper will discuss the operation and maintenance of Molycorp's Quests Mine ore conveyor system. The 1.2 m wide, steel cable-reinforced conveyor belts are capable of transporting 1089 kt/h of ore over a belt line distance of 3124 m with a vertical rise of 518 m. A portion of the conveyor runs in a 2057 m long underground decline on a 10° slope. Six 448 kW motors power the main 1.2 m wide belts.

Jan 1, 1984

By Fernando Jorge Dick

Artificial sulphides have been produced on the surfaces of heavy metal-oxide, minerals at elevated temperatures (1) and these sulphides gave consistently similar flotation characteristics as the respective natural sulphides. In the case of tin, the only natural tin sulphide known is herzembergite (SnS) which is found only in minor quantities, and its flotation behavior is not known. Balberyszki, Dorenfeld, and Carmi reported (2) tests with artificial tin oxide and pure cassiterite treated with hydrogen sulphide at temperatures above 750oc. They confirmed that the product could be floated in acid pulps. However, iron sulphides derived from pyrite, limonite, and hematite which are generally the major impurities in tin bearing ores could not be separated from tin sulphides under the conditions used by previous investigators. As a practical matter, if complex tin ores or complex low grade tin concentrates are to be treated by this process, it is necessary to be able to separate sulphidized cassiterite from other sulphidized minerals in the feed. The major metallic minerals, by weight, in complex tin ores are the iron minerals--pyrite, hematite, limonite, magnetite and pyrrhotite. These minerals become (or remain) sulphidized during the sulphidization process.

Jan 1, 1978

By Miguel Reyes, Mathew Girman, Chenming Zhou

Modern smart mining increasingly depends on sophisticated electrical and electronic systems for improved safety and productivity. With more electronic systems being introduced underground, the mining industry faces electromagnetic compatibility (EMC) issues caused by electromagnetic energy emitted by one device adversely impacting the normal function of another. This paper provides an overview of EMC and electromagnetic interference (EMI) research for underground mining, including a review of EMI in other industries applicable to mining, published EMI research pertaining to mining applications, representative EMI incidences, related EMI legislation in mining, and mitigation strategies.

Jan 3, 2022

By N. Magdalinovic

Generally speaking, erosion, as a process which entails degradation of surface layers of earth under the influence of the mechanical energy of surface waters, and from the point of view of biosphere sustainability, is a harmful process. This is absolutely true when agricultural and forest areas are concerned. However, if erosion is viewed selectively, this general definition about its harm raises serious questions. In other words, the erosion which takes place in the terrains where there is no vegetation because of the geological composition of the soil, does no harm. On the contrary, if the mineralogical composition of such terrains is characterized by a presence of precious and rare metals, erosion can be very useful. It contributes to the creation of new alluvial deposits of these metals in the waters in the plain land. It is here that torrents from hills come down and cause erosion. And finally, if there were no erosion, there would be no renewable deposits of gravel and sand.

Jan 1, 2007

By C. K. Arthur, N. K. Dumakor-Dupey, B. A. Kansake, F. A. Kaba

Autonomous mining systems have been deployed for improving mine performance. However, there is a fear of job losses. Adoption of autonomous systems is envisaged to be resisted by major stakeholders in Ghana due to high illiteracy and unemployment. This paper assesses the preparedness of Ghanaian mining stakeholders for the adoption of autonomous systems to Ghana’s surface mining industry. Closed and open-ended questionnaires were administered to mine stakeholders. Respondents generally expressed unwillingness to accept autonomous systems into Ghanaian mines due to fear of increased unemployment. We propose setting up a mining education fund (MEF) for training stakeholders in autonomous mining systems. INTRODUCTION Mining contributes enormously to the sustenance and growth of global and national economies through the provision of raw materials, employment, revenues and foreign exchange (Carvalho, 2017; ICMM, 2017; Cordes et al., 2016; Solomon et al., 2008; Walser, 2000). The International Council on Mining & Metals (ICMM, 2014) reported that globally, formal mining employs approximately 2.5 million people. Many resource-rich countries, especially the developing ones, have experienced strong socioeconomic growth propelled by the discovery and extraction of valuable minerals. McMahon and Moreira (2014) reported a positive linkage between mining and sustainable development. They revealed that averagely, resource-rich countries have improved Human Development Index (HDI) scores than countries without mineral resources. Mining remains a crucial industry in Ghana’s economic development (Bermúdez-Lugo, 2016; Amponsah-Tawiah and Dartey-Baah, 2011). Over the years, mining has contributed significantly to the gross domestic product (GDP) of Ghana. In 2013, mining accounted for 1.7% of Ghana’s GDP and about 19% of government revenues (Ghana Chamber of Mines, 2015). The Ghana Chamber of Mines also reported that mining contributed over 50% of foreign direct investment, 37% of export earnings and 1.1% of direct employment revenues. The US Department of Energy (DOE) estimates that 65% of coal, 92% of metals and 96% of industrial minerals are mined using surface mining methods (DOE, 2007). Generally, mining is a capital-intensive venture, with high operating cost, hence there is a constant demand for mining companies to seek efficient cost reduction and production maximization strategies. One strategy being pursued keenly is automation, which is noted to improve productivity, and worker safety at minimal cost. According to Parreira (2013), mining automation involves direct teleoperation whereby workers remotely control the mining process using computers from a control room.

Jan 1, 2019

By H. L. Lovall

Huge banks of preparation plant refuse and other non¬saleable materials have accumulated over the years in all major United States coal producing areas. These banks, esthetically and commercially undesirable, can cause air and water pollution and land reclamation and mineral conservation problems for the industry and nearby communities Although some refuse banks have been reworked to recover saleable coal, all remain and accumulation continues. Even those previously processed continue as potential hazards. Among the several problems created by refuse banks, in situ combustion is most treacherous. Of the millions of tons of major accumulations, there are at least 450 refuse banks on, fire at this time Attempts to extinguish such fires are costly, impractical and generally unfruitful. Studies are in progress to evaluate the potential of processing such materials to eliminate the combustion capability and to yield usable fuel and nonfuel products. Aspects of the study now in. development for coal refuse include: (a) evaluation of characteristics (size, sink-float, ash, sulfur and calorific value) of the coal refuse materials which are known to be highly variable, (b) development of an ignition test having significance for in situ conditions, (c) study of processing capabilities (comminution for liberation, pilot plant washing tests), and (d) investigation of potentially significant properties of fuel and nonfuel products which could be altered to enhance their market potential.. Among the latter products are lightweight aggregate, fill for mine slushing operations, construction, etc: Plans are to extend the studies to include the design, erection, and test processing of refuse with a transportable plant,; which could provide basic economic and product utilization data from several locations

Jan 1, 1964

By Sandip K. Mukherjee

This paper describes the application of pressure foam to control respirable dust in a double-drum longwall mining section. The feasibility of passing an adequate quantity of pressure foam through the shearer drum was initially established in the laboratory. Thereafter, underground testing of the foam system to determine its effectiveness on an active operating longwall was conducted in a mine in West Virginia. The foam system proved superior to the water spray system. The de- tails of the laboratory and field investigations, the results obtained, and the degree of acceptance of this system by the mining company are discussed in this paper.

Jan 1, 1984

By C. B. Clemmens

Accurately predicting ground control conditions before mining requires a comprehensive exploration approach including photogeologic mapping (satellite and low altitude), delta modeling and, particularly, geophysical logging. In situ properties, density; strength indices; grain size; clay content; and aquifer location, can be estimated with this inexpensive technique. Geophysical measurements can be spot-checked by field or laboratory tests on core samples and by hydrologic (pressure) testing. Each phase of drilling should be accompanied by refinement of the delta model, facilitated by log signatures. Measured properties can then be projected into geologically similar areas. A properly planned program will delineate both the "worst-case" and normal support conditions. Suspect areas can be avoided by mine layout and the mine plan can contain support contingencies for anticipated trouble spots.

Jan 1, 1985

By J. Gibson

"INTRODUCTION As one of the most pressing and important political debates of this century, climate change has captured global attention and is forcing governments to take action towards decreasing GHG and carbon emission levels below what was previously thought to be necessary. With the ever-increasing price of diesel fuel accompanied by the popular topic of carbon taxes and greenhouse gas emissions, the mining industry is looking to industry specialists for assistance. The benefits of a no-idle policy reach far beyond carbon reduction and fuel savings, ranging from decreased maintenance to increased engine life. With products like battery powered A/C systems and diesel-fired heaters, going no-idle is easier today than ever before. With both systems being manufactured to withstand the harsh environments of the mining industry, the end user will see a seamless change from conventional, inefficient belt-driven systems to future, stand-alone mobile equipment HVAC. THE HISTORY OF GHGS AND CLIMATE CHANGE In 1896 Svante Arrhenius first claimed that the combustion of fossil fuels may eventually result in enhanced global warming, but not until 1955 did Gilbert Plass draw global attention to global warming by summarizing that adding carbon dioxide to the atmosphere would intercept infrared radiation and thus warm the earth. Then in the early 1960’s Charles Keeling developed modern technology to produce concentration curves for atmospheric CO2 (Figure 1). In 1988 the Intergovernmental Panel on Climate Change (IPCC) was founded by the United Nations after acknowledgement of a rising global annual temperature. The IPCC consists of over 2500 scientific and technical experts from more than 60 countries, and because climate change could not be solved by a single country, the Kyoto Protocol was negotiated in 1998 requiring all participating countries to reduce their GHG emissions by at least 5% from the 1990 levels. The Protocol was signed by 186 countries in 2001 (since then several countries have retreated from the agreement, including the United States)."

Jan 1, 2015

By C. O. Lee

The Grand Isle Sulphur Mine is located in the Gulf of Mexico, approximately seven miles off the coast of Grand Isle, Jefferson Parish, Louisiana. The depth of water at this location is about 50 feet. The deposit is on acreage covered by oil, gas, and mineral leases which were originally issued in favor of Humble Oil & Refining Company by the State of Louisiana, and which were continued, maintained, and redesignated by the Department of the Interior of the United States, pursuant to Section 6(b) of the Outer Continental Shelf Lands Act. On September 19, 1956, Freeport Sulphur Company acquired from Humble Oil & Refining Company the sulphur rights underlying the tracts. This assignment was approved by the Secretary of the Interior on July 12, 1957. The Director, United States Geological Survey, approved Freeport Sulphur Company as Operator on July 31, 1957. Actual design began in September 1956; the first structural contract was let December 15, 1957, and offshore erection began in June 1958. The initial phase of construction will be completed and production started in early 1960. The estimated total cost of the project is $30,- 000,000, of which $8,000,000 is the extra cost for being in the Gulf of Mexico.

Jan 1, 1959

By Akram Marseet, Andrew J. Petruska, Rik Banerjee

Underground mine roof bolting is a crucial operation for miners’ safety and mine sustainability. Since roof bolting is a manual or human-supervised operation, miners’ safety is at risk due to dust or rock falls. Traditional machine learning algorithms have shown limitations to detecting drillable areas, mainly due to harsh lighting conditions. The authors propose an adaptive deep-learning framework for autonomous roof bolting. The proposed framework is based on implementing a binary semantic segmentation algorithm on color images to classify pixels that belong to rock from those that belong to non-rock. Significantly, the proposed framework implements deep learning semantic segmentation on images from traditional and neuromorphic vision sensors in underground mines. The performance of the proposed model shows an impressive accuracy level of at least 98% at a low number of training epochs with smooth learning curves. The high accuracy enables the implementation of autonomous roof bolting, greatly improving miners’ safety and operational efficiency while reducing human exposure to safety hazards. This research will advance the use of deep learning in mining automation and has the potential to revolutionize the traditional mining industry.

Feb 1, 2024

By Jim Huerta

Diesel fuel usage in the mining industry continues to escalate. This is because approximately 60 percent of all mined materials are surface extracted by large equipment using diesel fuel, which continues to increase in cost per gallon. For example, coal mining uses large equipment such as wheel loaders, wheel dozers, draglines and [ ] dredgers. In one year, three of the largest U.S. coal mining operations consumed approximately 567 million to 852 million L (150 million to 225 million gal) of diesel. At an approximate cost average of $3.25/gal the expenditure on diesel is $487 million to $731 million per year. So, are there any solutions that could reduce this cost burden? Yes, there are. Coal mining companies can extract less ore; use more efficient extracting equipment that consumes less fuel; wait for a significant reduction in the cost of fuel; or find and use technology that would create efficiencies that would lower the cost. Nanotechnology is one such technology that might provide the means to create the efficiencies that will significantly lower diesel fuel costs.

Jan 1, 2011