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Research workers from the Bureau of Mines and industry met with other government and industry representatives at the Mont Chateau Lodge, Morgantown, W. Va., on May 30-31, 1973, to discuss the current status of methane control in eastern U.S. coal mines. The opening remarks, the eight technical presentations, and the discussions of the members of a government-industry panel are published here for the benefit of those concerned with the control of methane in coal mines. In addition, an introduction has been added to present the background of work in this field.

Jan 1, 1973

By W. A. Lang

Introduction Under our present civilization, industrial developments will be greatest in those areas in which energy .can be most economically produced and efficiently used, where labour is in adequate supply, and where markets for the products of industry are available. A knowledge of fuels- the present major sources of energy- and of their utilization is therefore of vital importance. With that in mind, the aim in this paper will be to outline the known reserves of fuels in Alberta, to give their characteristics, to indicate the markets served by each, and to offer some suggestions for the future development of the coal industry. The paper should be regarded as a compilation of published data rather than as an original treatise. Alberta is richly blessed by having large reserves of mineral fuels. The estimated reserves of coal are 46,562 million tons. Alberta is the oil and gas province of Canada. The world's largest deposit of bituminous sand occurs along the Athabaska river in Alberta. In addition, there are large areas of forested land in the northern and western sections of the Province, and the rivers serve for the development of hydro-power.

Jan 1, 1949

By J. Phillip Mackey

A whole new group of non-ferrous pyrometallurgical processes with the ability to utilize tonnage oxygen and capture sulphur dioxide were developed and commercialized over the period 1940s–1980s. Many of these earlier process developments were undertaken with limited knowledge of the process chemistry and influence of key process variables; in many cases, piloting helped provide much new physico-chemical data, but gaps remained. The second generation versions of these technologies of today provide all the primary copper, nickel and lead produced worldwide by pyro-metallurgical smelting. Further, process development has continued and a new generation of copper and lead smelting technologies have also been developed in China since the 1990s. The older reverberatory and blast furnaces have been progressively replaced by the newer technologies—a good example being the introduction in 1992 of the copper IsaSmelt technology at the Mt. Isa smelter in Australia where the former fluid bed roaster and reverberatory furnaces were replaced by a single new smelting unit, together with an acid plant for sulphur dioxide collection. The development of these new technologies was made possible by investment in fundamental and applied research. The lesson for the future is, in order to sustain these improvements, continued investment in research and development capability is required—to do otherwise is to risk obsolescence and lack of competiveness in the world market. Dr. Peter Hayes at The University of Queensland is one of the many researchers and process engineers who have contributed to the fundamental understanding of metallurgical processes over this period of rapid change in technologies. The present paper briefly outlines some of the many contributions Peter Hayes has made to the understanding of kinetics, mechanisms and phase equilibria in metallurgical systems, and metallurgical process development.

By P. J. Mackey

A whole new group of non-ferrous pyrometallurgical processes with the ability to utilize tonnage oxygen and capture sulphur dioxide were developed and commercialized over the period 1940s–1980s. Many of these earlier process developments were undertaken with limited knowledge of the process chemistry and influence of key process variables; in many cases, piloting helped provide much new physico-chemical data, but gaps remained. The second generation versions of these technologies of today provide all the primary copper, nickel and lead produced worldwide by pyro-metallurgical smelting. Further, process development has continued and a new generation of copper and lead smelting technologies have also been developed in China since the 1990s. The older reverberatory and blast furnaces have been progressively replaced by the newer technologies—a good example being the introduction in 1992 of the copper IsaSmelt technology at the Mt. Isa smelter in Australia where the former fluid bed roaster and reverberatory furnaces were replaced by a single new smelting unit, together with an acid plant for sulphur dioxide collection. The development of these new technologies was made possible by investment in fundamental and applied research. The lesson for the future is, in order to sustain these improvements, continued investment in research and development capability is required—to do otherwise is to risk obsolescence and lack of competiveness in the world market. Dr. Peter Hayes at The University of Queensland is one of the many researchers and process engineers who have contributed to the fundamental understanding of metallurgical processes over this period of rapid change in technologies. The present paper briefly outlines some of the many contributions Peter Hayes has made to the understanding of kinetics, mechanisms and phase equilibria in metallurgical systems, and metallurgical process development.

By Wils L. Cooley

Two major grounding topics are covered: mine ground systems and ground-check monitors. Performance characteristics of ground-check monitors for high-voltage surface mine distribution cables and low-voltage underground mine trailing cables are evaluated. Over 20 commercially available monitors are studied to determine their utility. Several monitoring concepts are incorporated into an unusual monitor design, the prototype of which is described in detail. A comparative study of the effectiveness of several alternate methods of grounding surface mine equipment supports the system currently proposed by MSHA. An instrument design to measure earth voltage gradients is described, as well as an instrument design for measuring the effectiveness of dc haulage current return systems. An extreme analysis is made of techniques for measuring earth resistivity and resistance of safety ground beds. Electrolytic corrosion studies of earth electrodes are reported extensively also.

Jan 1, 1979

By E Beltran, S Ngunz, F Orrante, F van Zyl, M Westcott

"The primary control objective of the project is to achieve milling optimisation by ensuring that the energy available for rock breakage is used as efficiently as possible. This is achieved by increasing the level of mill filing until a process constraint is reached. Stable operation against this limiting constraint is then maintained to ensure long-term optimised operation.Semi-autogenous grinding (SAG) mill control optimisation presents a number of challenges. SAG mills have multiple inputs that are used to control multiple outputs (MIMO process). Secondly, the SAG mill loading process is a ‘high inertia’ process that can be approximated as an integrating process. This means that it is open-loop unstable. The hybrid control strategy presented implements an advanced ‘load stabiliser’, which transforms this integrator process into a more manageable first order process, which can be steered stably against the constraints. This SGS hybrid Expert control strategy implemented on both SAG mills at the Porgera concentrator therefore consists of two integrated parts responsible for:stabilising the mill load to a targetdriving the mill load target to the maximum determined by the process constraints (eg maximum power draw) to maximise efficiency and throughput. A comparative study is done between the operation of the plant for a period of a month before and a month after the implementation of this strategy. The results indicated a significant improvement in the SAG mills’ stability and operation as well as a reduction of overload situations leading to a loss of throughput.Citation:Ngunz, S, van Zyl, F, Orrante, F, Beltran, E, Westcott, M and Wilson, S, 2016. Simplified Hybrid Semi-autogenous Grinding Mill Control - Explanation and Practical Results at the Porgera Concentrator, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 313–320 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By O. H. Metzger

This is one of a series of capers being published by the Bureau of Mines on gold mining A the Western States. It describes the production of gold in the principal mining districts of New Mexico. The material was gathered red on a trip through tale State in the summer of 1936. ACKNOWLEDGMENTS The author acknowledges the aid and cooperation of mine operators in all parts of the State, who willingly contributed all information requested. Geological reports of the Geological Survey and the New. Mexico Bureau of Mince were drawn upon freely for information; credit to individual paper, is given in the text.

Jan 1, 1938

Conventional ferronickel smelting has five main steps: Drying, calcination, prereduction, smelting and refining. In the scope of the current work, smelting experiments were conducted using Sivrihisar laterite ores (1.26% Ni) of Turkey. The ore samples previously subjected to drying, calcination and prereduction stages were smelted in alumina crucibles in a laboratoryscale horizontal tube furnace under argon atmosphere. Smelting experiments were performed at 1500, 1550 and 1600 oC. The amount of excess coal used in prereduction step was another variable. Sivrihisar laterite ore is a limonitic one with low MgO composition. Therefore, MgO was added to the smelting charge as a flux. The effects of experimental variables on metal Ni content and slag composition were investigated.

Jan 1, 2012

By M. Mpofu, G. Stenzel, F. Magweregwede, B. Maphalala, T. Kgarume

Surface coal operations in which mining activities are conducted above old underground workings experience hot holes after drilling. In a coal mine, hot holes are defined as shot holes, which after being drilled have an in-hole ambient temperature of 40°C or above or show a temperature increase of 3°C or more during monitoring. Hot holes and other cavities, such as cracks, pose health and safety risks to workers, such as exposure to hot air and high concentrations of noxious gases released from these holes. In addition, workers may be exposed to premature detonation of explosives caused by in-hole temperature increases and chemical reactions. To this end, Coaltech Research Association commissioned a project to develop a Best Practice Guideline for the management of hot holes. This paper is a compilation of the activities conducted in the development of the Best Practice Guideline between 2021 and 2022. The activities included a review of standard operating procedures and hot-hole temperature-measuring and -monitoring devices, and the assessment of current hot-hole procedures at selected mines. The results indicated that management of hot holes requires a focus on pre-emptive risk assessment of mining blocks, identification of hot holes using the correct temperature-measuring devices, and continuous monitoring of hot holes from the time of drilling until just before blasting. Hot-hole management accessories, such as polyvinyl chloride sleeves, were found to be effective in insulating the hot-hole emulsion from the rock mass temperature, thus preventing the potential for premature detonation.

Sep 9, 2024

By F. W. Clark

At the present time, when lixiviation versus amalgamation is being so thoroughly discussed by practical men, and published information is so meagre, the following tests, made by students in the mining laboratory of the Massachusetts Institute of Technology, may be of interest to others. The ore experimented upon was obtained from the Sombrerete mines near Zacatecas, Mexico. A careful analysis of the dried sample resulted as follows : Per cent. SiO2,............62.79 S.............13.86 Al2O3............4.39 Fe,............11.26 Zn,............1.57 CaO.............2.91 MgO,........... 0.06 Cu,.............0.12 Pb,.............0.40 Sb and As,..........trace CO2,............2.35 Ag,.............0.16 99.87

Jan 1, 1886

By David R. Peterson

This report presents a deep ocean mining operational simulation which is capable of describing the response of the bottom collection unit to specified mining ship maneuvers and the corresponding operation of the mining ship maneuvering system. Bathymetry, obstacles, collector and pipe dynamics and ship maneuvering capabilities are included in the simulation. The simulation is capable of evaluating the technical requirements and operating costs for specified mine plans, Results are useful in assessing mine size requirements and provide operating 'cost 'estimates useful as inputs to deep ocean mining economic feasibility assessments, The simulation is used to determine the consequences of obstacles to mining system operations in terms of impact on mine size requirements and reduced production arising from obstacle avoidance maneuvers of a towed (unsteered) collector.

Jan 1, 1979

The Mt Sinivit gold project is located approximately 50km SSW of Rabaul in the Baining Mountains of the Gazelle Peninsula, East New Britain Province. The deposits were discovered in mid- 1983 and form part of a larger 26km long zone of variably aurif- erous quartz veining. There are no surface indications or previ- ous records of any prospecting activity or production from the region. The Mt Sinivit deposits consist of a series of oxide and sulphide reserves and resources contained in the Wild Dog (South- ern, Central and Northern oxide zones; Northern sulphide zone) and Kavursuki veins. The proposed exploitation of the oxide reserves by a series of small-medium sized open pits has been fostered by the PNG Department of Mining & Petroleum (DMP) as part of a government policy to encourage the development of a small-medium sized mining industry in the country. The aim of this paper is to document the steps and procedures involved in obtaining the grant of a Mining Lease emphasising the time and the expenditures required during each step of the approvals process for the Mt Sinivit project.

Jan 1, 1997

By E. G. Dahlgren, Dan O. Howard

THE West Edmond oil field, which covers parts of Oklahoma, Canadian, Kingfisher, and Logan Counties in the State of Oklahoma, is in geographical extent the largest single oil field found in the state. At the present time, its area of 26,800 acres is almost twice as large as the Oklahoma City field, which hitherto was the state's largest field. Many authorities believe that the West Edmond field is the most important oil pool found in the United States since Pearl Harbor. The discovery of the field without the help of geological, geophysical, or other recognized technical information, the fact that the oil and gas accumulated in a stratigraphic or wedge-type trap, and the rapid development of the productive area under wartime conditions are some of the interesting features of the field. The West Edmond field lies west of the Oklahoma City, Britton, and Edmond fields. The field is in an area that has been considered on the west flank of the Granite Ridge line of folding, on which a number of Central Oklahoma's most important oil fields are located. Over a period of years, especially since the discovery of the new pools such as Oklahoma City, Edmond, Britton, and Crescent, the general area of the West Edmond field has been explored intensively by geological and geophysical methods. This led at times to the drilling of a few dry Wilcox sand tests.

Jan 1, 1945

By Robert M. Cox

The objective of this study was to determine if significant relationships exist between coal mine roof stability and the time roof is left unsupported. Additional factors such as geology, opening geometry, and mining methods were also studied: to determine their relative influence on mine roof stability. The results of the study indicate that geologic factors such as shear zones (either joints or faults) and changes in roof rock lithology were the principal factors governing mine roof stability. The time lapse factor appeared to be of critical importance when poor mine roof conditions are encountered. The study pointed up the need for improved and permissible rock mechanics instrumentation for use in coal mine investigations.

Jan 1, 1974

By C Garrido, J Barrera, H Alvarez, L Perez, S Ramirez

In recent years, there has had a greater recurrence of studies and projects that consider tailings filtration followed by dry stacking to reduce the consumption of fresh water, the space required for disposal, and, eventually, to reduce the costs of the project. In addition, this technique could be required to meet new environmental restrictions to extend the life-of-mine of existing plants or to enable the development of new projects, especially in areas of high social interest. This article is intended to describe the most relevant technical aspects of the design and implementation of an iron ore tailings filtering system and its final overland disposal as well as physical and metallurgical surveys, and laboratory and pilot testing. Furthermore, it is presented how these activities are inserted in the project development to rationalise the resources. The case under study considers an iron mineral wet magnetic concentration processing plant. The outcome tailings are dewatered by means of thickeners, where the overflow water is recycled back to the plant. The underflow slurry is pumped into intermediate storage tanks before proceeding with further dewatering and final disposal. The project consists of a tailings filtration plant, belt conveying systems, a temporary stockpiling system, trucking loading and transportation system, moisture-conditioning facilities (spreading and airing), and final disposal facilities (compacting). Due to the stickiness of the filtered tailings that governs the belt conveying system design, the operating moisture range must be established. Besides, proper technical aspects such as planning, executing, and analysing both the laboratory and the pilot testing data to validate process design parameters; selecting filters; defining spare filtering capacity; handling the out-of-range filtrated moisture; sizing the belt conveying system; configuring the equipment involved, must be considered.

Nov 8, 2021

By R. H. Bedford

"The El Dorado copper mine is situated in the foothill copper-zinc belt of California, which traverses the western slope of the Sierra Nevada with unusual persistence from Butte County to Kern County, a distance of more than 300 miles. Although this area contains such important past producers as the Penn mine, Union, and others, a great part of the current production has been derived from smaller properties, which depend largely on premium metal prices for economical operation. The El Dorado mine is in the latter group, which constitutes an important source of metal in a national emergency.Exploration by the Bureau of Mines by means of eight diamond-drill holes Indicated narrow, intermittent lenses of copper ore along structures boo feet in length. The copper occurs in massive sulfides composed of chalcopyrite, pyrite, pyrrhotite, and minor quantities of bernite. The sulfides have evidently replaced tuffs, which are interbedded with the Mariposa slates and shales.H. A. Weiler and Hal T. Hall, owners of the El Dorado copper property, requested an examination by the Bureau during the latter part of 1914. In December of that year an engineer of the Bureau of Mines visited the mine and recommended the project work undertaken. The purpose was to aid the owners in bringing the property into production of copper and zinc, which at that time was critically essential to the war industries.Complete factual data obtained by the exploration are embodied in this report.In its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G, Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director.Acknowledgment is made to A. O. Johnson, chief, Reno Division, Mining Branch, and Lowell B. Moon, chief, Mining Branch, for their aid and direction."

Jun 1, 1946

The thirty-second regular meeting of the Rocky Mountain Coal Mining Institute was called to order at ll: 40 o'clock A. M., Monday, February 26th, 1934, President L. R. Weber presiding. Misses Helen Kelly and Marian Rodell presented President Weber with vases of flowers in behalf of the Institute. On motion of Harry Bubb, duly seconded, it was voted that the reading of the minutes be dispensed with, inasmuch as they are printed in the proceedings. The President made hi annual report. The Secretary-Treasurer made his annual report. The following committees were appointed by the President: Nomination s Committee-David Brown, chairman; G. A. Knox, G. C. Davis, George B. Dick, Walter Bachman.

Jan 1, 1934

By Meng Li, Hao Nie, Weitian Ding, Mamdouh Omran, Ying Li, Yao Ge, Yaowei Yu, Abourehab Hammam, Lei Zan

This study examines the isothermal and non-isothermal reduction behaviors of iron ore compacts in a pure hydrogen atmosphere and compares the results obtained during the reduction process by CO. The different phases accompanying the reduction reactions were identified using X-ray diffraction (XRD) and its morphology was microscopically examined. In isothermal experiments, temperature plays a significant role in the reduction process. At any given temperature, the reduction rate during the initial stages is higher than that during the final stages. The reduction rate in H2 atmosphere was faster than in CO gas. The comparison of activation energy values suggested that reduction with H2 is more efficient thanwith CO. At the same temperature, the time required to achieve a certain degree of reduction was lower when using H2 gas than CO atmosphere. In non-isothermal tests, the heating rate has a significant effect on the reduction rate and reduction extent. At the same heating rate, the degree of reduction was higher in H2 atmosphere than in CO gas. Based on experimental data, the parameters of reaction kinetics were deduced by application of model-free and model-fitting methods. The reduction in H2 atmosphere was controlled by nucleation model (Avrami-Erofeev model), while the CO reduction reaction was controlled by gas diffusion.

Sep 29, 2020

By M. Rieber

The potential for the wide-spread commercialization of superconductivity, the disappearance of all resistance to a direct current (D.C.) electric flow, began in 1986-87 with the development by Bednorz and Muller at IBM's Zurich Laboratory of an yttrium -barium -copper oxide conductor which attained zero resistance at 90t:. Although the status of superconductivity is still pre-bench scale, it is useful to forecast its probable effects on the copper industry. I t should not be forgotten that at their inception, the impacts of transistors, semi-conductors, thin films and fiber optics on the electric/electronics sector of this industry, were largely underestimated. Superconductors are not metals, but a class of ceramics. They represent an efficiency increase of one or more orders of magnitude. If their development is to be a boon to the copper industry, rather than a reduction of metal demand through miniaturization or material substitution, vastly expanded copper containing electrical uses must be in prospect. In this paper the projected uses of high temperature superconductivity are examined, followed by the remaining problems to be overcome. Assuming success, a time horizon for maturation is estimated. The penalties for the non-recognition of new markets and material substitution are shown on the basis of past forecasts. Finally, the application of successful superconductivity to the copper industry over the forecast period is estimated.

Jan 1, 1990

By J. R. Thoenen

This paper outlines briefly results of seismic measurements recorded in the vicinity of quarry blasting under practical operating conditions. The data cover field work done from January to the middle of August 1930, during which time records were made of 61 blasts in 19 quarries. Of the tests made, one was in biotite-gneiss, two in dolomite, two in a flintlike volcanic complex, three in gabbrodiorite, five in trap rock, and six in limestone. One quarry was in Alabama, two were in South Carolina, two in New York, four in Kentucky, five in Connecticut, and five in Massachusetts. Explosive charges ranged from 0.30 pound to 41,900 pounds, and the method of shooting varied from mud caps through hammer and wagon drill holes to churn drill holes and coyote tunnel shots.

Jan 1, 1937