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By Frank E. Williams

Nuclear detonation data were accumulated, studied, and evaluated by the Bureau of Mines to visualize how nuclear explosives might be used in a shale?-oil industry, The evaluation shows that the Green River Formation at the semi-isolated locale of Piceance Creek Basin, in northwestern Colorado; is thick and widespread enough to warrant consideration of nuclear mining in lieu of conventional methods, Because cost data for nuclear explosions are limited; cost comparisons are made largely by assumptions. Also described are the history of the shale-oil industry, the geology and size of oil-shale resources; and conventional mining methods and processing technology.

Jan 1, 1969

By D. J. Parker

On Thursday, March 18, 1937, the country was shocked by news of a terrific explosion at the New London, Tex., school, which caused the death of 280 pupils avid 14 teachers. The explosion occurred at about 3:05 p.m. in the largest of the 11 school buildings on the campus. Fire 1 shows this building, marked "Main high school building", with respect to other buildings, pipe lines, oil wells, and gas lines or the property.

Jan 1, 1937

The BHP Billiton Cannington Mine uses paste as the principal method of backfill. The paste consists of mine tailings and cement. The pastefill process at Cannington includes a surface plant where the thickened total tailings stream is filtered using two vacuum disc filters operating in parallel. The filter cake is mixed with Portland cement in a spiral mixer to produce a paste at a specified yield stress and cement content. The initial system design only required paste to be delivered under gravity. In July 2001, Cannington Mine expanded to 1.8 million tonnes per annum. In order to achieve this, production commenced on five new levels underground, 350 metres horizontally from the paste plant. Due to the high viscosity of paste, this distance was too far to transport by gravity. Traditionally, paste has been transported only short distances (50 m) using positive displacement pumps, with very limited success. At Cannington, a conveyor was installed which was designed to achieve zero spillage into the environment. This paper discusses the innovative design strategies used to attain zero harm on the environment whilst conveying a material, which is difficult to transport.

Jan 1, 2002

By T. R. Kostecki, J. Hirschi

"Analytical engineering design is based upon a trial-and-error iterative and deterministic process. Within this process, the engineer obtains some estimated values, plugs them into de facto closed-form equations, and receives output, which is expected to be a single number that serves as the basis for the design. This number is typically a factor of safety, or some other equivalent strength-stress ratio. This provides the engineer with a quick and relatively quantitative design methodology. This can create problems however, because in mining applications, the actual in situ system is highly variable, complex and often chaotic, which can lead to potentially incorrect conclusions that result in unsafe designs. A more appropriate and reliable approach is a probabilistic analysis for engineering design. This process is used widely in civil and other engineering disciplines, but is often overlooked for applications in coal mine design. Additionally, it seems the amount of past studies using this approach, especially in coal mine design, are rather limited. Considering how the probabilistic approach can account for uncertainty in parametric values and how unpredictable a mining design can be, the authors believe that this approach has potential in mining. This paper will focus on a summary of past studies related to probabilistic analysis in coal mine pillar design and provide recommendations for future work that could improve design reliability. INTRODUCTIONFeasibility and fundamental design procedures for excavations often start with an assessment of mine openings, pillar design, and the surrounding structure by using a deterministic approach with closedform solutions (ex. Bienawski, Obert-Duvall). These are reliable methods, but designers know that the inputs in these closed-form solutions are estimates at best and do not incorporate any degree of uncertainty. This is therefore not an optimal design procedure.A more appropriate design should incorporate some uncertainty because of the chaotic and variable nature of geology and mining conditions in general. In an attempt to account for uncertainty, a probabilistic approach can be adopted, which accounts for deviations in variables and provides a more optimum design solution. By applying a probabilistic approach, a designer can look at multiple failure scenarios at the same time instead of using the same deterministic design over and over."

Jan 1, 2015

By Michel Ruel, Ali Soltanzadeh, Benjamin Légaré

High fidelity commercial process simulation packages can be used at different stages of a greenfield project, from initial plant design to operator training in the later stages. However, there are several factors that make the software less attractive for small and medium size brownfield projects, such as the licensing cost and the fact-finding manpower required for model design and simulator maintenance. In this paper a different approach is described. The knowledge gathered from operating personnel was used to implement higher level models based on plant data, operating heuristics, and experience rather than detailed component-level models. The computing platform used was a low-cost, well-established, control system vendor-independent software. Throughout this paper we demonstrate the success of implementing this model-based approach using two industrial examples. The first example is a simulation of the carbon monoxide (CO) distribution system at a metallurgical complex. The purpose of this simulator was to test new control strategies and PLC programs prior to implementation. CO being a toxic combustible gas, validation of the suggested control system changes was necessary for plant safety. Simulation of specific operating conditions helped alleviate concerns and improved plant-wide acceptability of the new operating philosophy. The second example is a boiler simulator at a petrochemical plant. The operator training simulator (OTS) was designed as a platform for experienced operators to practice handling rare or abnormal conditions. A customized medium-fidelity model was developed for this targeted application where the cost of a full scale high-fidelity model could not be justified.

Jan 1, 2016

By C. A. Young, J. D. Miller

Adsorption isotherms previously determined by in-situ Fourier transform infrared/internal reflection spectroscopy (FT-IR/IRS) for oleate adsorption at calcite and fluorite surfaces near pH 9 and at various temperatures are compared. Results indicate that, at both mineral surfaces, chemisorption occurs at equilibrium concentrations below approximately l x l0-5 M oleate while calcium dioleate surface precipitation occurs at higher equilibrium oleate concentrations. The extent of chemisorption at the calcite surface is 3 to 5 times less than that at the fluorite surface while the extent of calcium dioleate surface precipitation on calcite is nearly a magnitude larger than that on fluorite. However, for both minerals, surface precipitation decreases with increasing chemisorption. Contact angle measurements and flotation recoveries show the hydrophobicity of fluorite to be greater than that of calcite at each of the temperatures and oleate concentrations studied. Significant differences are noted only in the chemisorption region. Unlike calcite, the hydrophobicity of fluorite was sensitive to the presence of oxygen in the system. Multichannel Laser Raman Spectroscopy (MLRS) showed this behavior was caused by the double-bond reactivity of adjacent chemisorbed oleate molecules and subsequent formation of an epoxide/polyether complex at the fluorite surface. Such a reaction product could not be detected at the calcite surface. These differences in adsorption density, hydrophobicity, and polymerization behavior are discussed in terms of the intrinsic surface properties of the minerals.

Jan 1, 1999

By Arthur F. Wendt

The following experiments and researches were originally conducted by Dr. Heinrich Rcessler, chief of the German Gold and Silver Parting Establishment at Frankfort-on-the-Main, for the sole purpose of abating the nuisance created by the discharge into the air of the sulphurous and sulphuric acids generated in the process of parting bullion by sulphuric acid. The results achieved have, however, an important bearing not only on this process, but are of value in the manufacture of sulphuric acid and sulphate of copper from sulphurous gases derived from any source. It has now been in successful operation for a term of years at Dr. Roessler's own works, and has been lately introduced with satisfactory results at the royal mints of Kremnitz and Munich, and the well-known establishment of Johnson Mathey & Co., of London.

Jan 1, 1884

By T. Petrov

This study was performed to analyze the behavior of the blowing curtain face ventilation system modified with a specially designed regulator, called Wing Regulator. The purpose of the regulator is to extend the airflow penetration depth toward the face and allow effective face ventilation at curtain setback up to 13.7m (45ft) from the face. A small scale model of the Wing Regulator was successfully tested in the Mine Ventilation Laboratory at the University of Kentucky. Then a prototype of the proposed regulator was tested in full-scale in mine environment. Series of three dimensional simulations were performed to support this research using validated CFD code. This paper presents results of the performed studies and discuses the advantages of using the Wing Regulator. Presented information relates to the US Provisional Patent Application No 61/818,112.

Feb 23, 2014

By S. J. Hussey

This Bureau of Mines report presents a discussion of the statistical approach to the design of experiments and indicates, by concrete examples, how and when statistical design is essential for obtaining meaningful data with a minimum number of experiments. Every research worker plans his work and designs his experiments in a manner which, based on his experience, seems most rational to him and which he believes will produce the information essential for resolving the problems. If the results obtained are open to multiple interpretations and are not of definitive reliability, the failure of the experiment design to produce the desired information may be due to several causes, These include faulty judgment in selecting the factors to be tested, ignoring the importance of interaction between factors, failure to adequately control test variables, and assuming that meaningful trends in the results can be identified without comparison to a predetermined experimental error. An experienced researcher probably will deduce from the nature of the data obtained that the design is faulty and may by trial and error ultimately arrive at the correct solution to the problem. Statistical methods of planning research minimize the chance of faulty experiment design, embody concrete procedures for testing the validity and reliability of the test data and for indicating mandatory changes in the design, and enable the researcher to obtain meaningful information with the least number of tests.

Jan 1, 1963

By McClelland. John J.

This Bureau of Mines report discusses recent applications of water in-fusion technology to control dust in U.S coal mines and presents recommended guidelines for determining coal seam infusibility. The techniques required to use water infusion are presented in detail. A Bureau case study indicated that water infusion reduced dust levels by 68 pct along a longwall plow face, bringing this section into compliance with the Z.0-mg/m3 Federal dust standard. Similar studies conducted by Occidental Research Corp. under a Bureau contract show water infusion at two longwall double-drum shearer operations produced dust reductions ranging from 38 to 50 pct. Water infusion was found to be cost effective, aver-aging 5 cents per ton.

Jan 1, 1987

By Brian Hays, Victor Mwaba

Optimization of water use has become a top priority for virtually every mining operation. The mineral extraction process typically requires vast quantities of water, which can be particularly challenging when a mine is located in an arid location. Most mining permits have very strict limits on water usage, so tight control of water utilization and extensive recycling are critical to regulatory compliance and profitability. Water management is not only dependent for selecting the right flowmeter for different applications.

Apr 1, 2026

By D. J. Parker

On Thursday, March 18, 1937, the country was shocked by news of a terrific explosion at the New London, Tex., school, which caused the death of 280 pupils rind 14 teachers. The explosion occurred at about 3:05 p.m. in the largest of the 11 school buildings on the campus. Figure 1 shows this building, market; "Main high school building?, with respect to other buildings, pipe lines, oil wells, and gas lines on the property.

Jan 1, 1937

By N. R. Thornton

This paper discusses the rapid growth in the application of instrumentation for metallurgical process control. It covers such methods as ultrasonics, pulp density measurements, on-stream X-ray analysis and reagent control, as well as the expanding use of computer control and data acquisition.

Jan 1, 1971

By R. Addison, T. Swendseid, R. Kehmeier, D. Larsen, J. Uhrie

"The development of a mining project necessarily progresses through many steps, beginning with the identification of a mineral resource and continuing through project construction. Several classifications of engineering study development are described, including preliminary economic assessment (PEA) or scoping studies, prefeasibility studies (PFS), feasibility studies (FS) and regulatory codes, each with a specific project organizational objective. This paper addresses the PEA, PFS and FS types of reports that are used by companies to evaluate projects, meet regulatory requirements and seek financing. The minimum requirements for engineering studies, focusing on the needs of financial institutions considering investment in a project, are outlined. IntroductionThe financing of mining projects in recent years has come under increased scrutiny by financial institutions owing primarily to an increasing percentage of projects whose capital expenditures had overrun project budgets or had failed to produce the economic returns anticipated during the project development process. Often, unfavorable project outcomes are not the result of widespread failures of the project engineering process but arise from inadequate engineering in limited specific areas of the project scope, such as overestimated mineral reserve, inadequate mine design, insufficient metallurgical testing or underestimated capital costs. Mill facilities and process infrastructure typically are responsible for up to 80 percent of the capital expenditures required by greenfield mining projects. They are often the project areas where capital costs are inadequately developed, and consequently are the areas highly scrutinized by financial institutions. This paper offers a perspective on the level of engineering expected by financial institutions as a prerequisite to committing support to developing mining projects.The evaluation of a mining project from exploration through development and production is a lengthy and complicated process. Mine development commitment activities for a potential project are initiated when a mineral resource is identified and continue through to the start of construction. The technical feasibility and the economic viability of each project are determined during the phases of mine development with more detailed engineering data required at each stage. There are at least four levels of engineering studies during development that are commonly acknowledged by the mining industry:"

Jan 1, 2016

By J. Marts

Underground longwall coal mining sections are operated as sealed gobs if the coal is prone to spontaneous combustion. Sealing along the gate roads during longwall face retreat limits the flow of fresh air (oxygen) into the gob and, thus, deprives the spontaneous combustion reaction of oxygen. In a project sponsored by the National Institute for Occupational Safety and Health (NIOSH), researchers at the Colorado School of Mines have used computational fluid dynamics modeling to simulate the flow of gases in sealed longwall gobs. The models were validated using measurements and observations from the field and demonstrate that targeted injection of nitrogen along the gate roads inby the face can be used to control the size and location of explosive methane clouds within the gob and to minimize or eliminate the explosion hazard resulting from the formation of flammable methane-air mixtures.

Sep 1, 2013

By AIME AIME

THE fall meeting of the Petroleum Division, held at Tulsa, Okla., on Oct. 11 to 14, devoted two days to technical sessions and two to field excursions. A representative attendance of 250 to 300 engineers and operating officials engaged in oil production marked the sessions and paid close attention throughout to a notable series of highly technical papers. Restricted as the program was to consideration of production problems only, the time proved too short for discussion or even the presentation of the 20 papers submitted. Much informing and pertinent discussion none the less took place, and the sentiment was general to the effect that the meeting was one of the best ever held by the Division. The meetings were held in the auditorium of the Municipal building and local arrangements were well looked after by the Mid-Continent Section of the Institute and the Oil and Gas Association. The combination of the three organizations served to bring together engineers and operators most usefully. F. Julius Fohs, chairman of the Division, presided at the sessions on Monday. Tuesday morning John M. Lovejoy of the local section took over this responsibility in the absence of T. E. Swigart, who was detained in California. The afternoon session was presided over by A. G. Heggam of the Oil and Gas Association and the Tuesday evening banquet by W. C. Franklin of the same organization.

Jan 1, 1926

By K. Muchima, C. Siame, L. Little, B. Kaputula, Q. Mclennan

"The variability of copper mineralization at Kansanshi mine significantly affects the efficiencies of the processes used to recover copper. Quantifying this variability is therefore essential for monitoring and optimizing the performance of the concentrator, which comprises three different flotation circuits (sulphide, mixed, and oxide) and an atmospheric leach circuit. Onsite automated scanning electron microscopy with energy-dispersive X-ray spectrometry (Auto-SEM-EDS) is used to analyse routine weekly composite samples for each circuit, providing detailed analyses of bulk mineralogy, copper deportment to different minerals, mineral liberation, and associations. Weekly mineralogical trends are used to assess changes in process performance, and characterization of the copper losses has inspired a number of projects to target the specific particle types responsible for the main losses. In this paper we describe the relationship between mineralogy and plant performance at Kansanshi, and discus IntroductionKansanshi is a copper and gold mine located in the Northwestern Province of Zambia, with an annual production in the region of 250 000 t of copper and 160 000 ounces of gold. Ore mined from the epigenetic vein-hosted deposit is classified into three ore types based on the extent of oxidation and supergene enrichment. Sulphide, oxide, and mixed ore are fed to separate mineral processing circuits tailored for recovery of the dominant copper minerals in each. After comminution to a target grind size of 80% passing 150 µm, each ore type is subjected to flotation to recover the copper sulphide minerals (chalcopyrite, bornite, chalcocite, covellite). The oxide float tails and a large proportion of the mixed float tails are then treated by atmospheric leaching to extract copper from the remaining copper-hosting minerals, which include cuprite, malachite, chrysocolla, and delafossite. Some native copper is recovered by flotation and some of it is recovered by leaching. A small portion of the combined concentrate from all circuits is subjected to high-pressure leaching and the rest is sent to the smelter. Sulphuric acid produced during smelting is used for the atmospheric leach."

Nov 1, 2018

By R. L. Montgomery

The heats of formation of lanthanum sulfate and the enneahydrate are -939.8 ± 3.1 and -1,587.1 ± 3.2 kcal. per mole, respectively. The heat of hydration is -32.5 ± 3.5 kca1. per mole. These values were obtained from heat-of-solution measurements of lanthanum oxide and salts. Low rates of solution precluded more accurate determinations of the thermal data. The heat of formation of the chloride was similarly observed to be -256.18 ± 0.28 kcal per mole. Heats of solution and combustion of lanthanum metal yield mutually concordant results, and earlier discrepancies reported in the literature may be ascribed to impurities.

Jan 1, 1959

By Howard V. Sears

Prospecting in its modern context means simply the gathering of information on which, to base plans for the utilization of our mineral resources. One prospecting system familiar to T. V. viewers is the pan of the old gold prospector which, while he prospected, could produce the wealth which financed him in his search. Present day geophysical "prospecting" systems, which are based on the real or supposed responses of an ore specimen, to various stimuli finder controlled laboratory conditions, are promoted as means of reducing the cost of prospecting. The universal drawback to all geophysical systems is that they yield "soft" data which are only presumed to be analogous to ore mineralization until they can be calibrated, by conventional prospecting systems, to each actual mineral environment being tested. By this time the system usually is no longer cheap. Since the raw data are too esoteric to be used until interpreted by geophysicists, usually in the light of their own personal theories and experience, the certainty of multiple interpretation is introduced. The concept of prospecting, at St. Joe Minerals Corporation's Viburnum, Fletcher and Brushy Creek mines in the new Missouri Lead Belt, encompasses surface diamond drilling for preliminary exploration, the sub¬sequent development of ore body tonnages and grades and the establishment of mining parameters. The predominantly flat-lying mineralized formation is mined by room and pillar stoping. In an operating mine, jackhammer holer are drilled in backs and bottoms of stopes, and chip samples are taken for assay, concurrent with mining. Thus irregularities in ore bodies or nearby discontinuities are not overlooked which are above or below the general mine

Jan 1, 1971

By J. E. Dutrizac

Canada is currently the world's largest supplier of zinc concentrates and is also a major producer of zinc metal. This dominant position in the world's zinc market is a fairly recent circumstance and, in fact, the country's zinc industry was founded only in the early part of the twentieth century. By contrast, the American zinc industry was well established by the mid-nineteenth century, largely based on technology originally imported from the still older European practice. Initial attempts to create a viable Canadian zinc smelter were based on the traditional practice and were unsuccessful; success came only with new electrolytic technology, much of which was developed domestically. The purpose of this paper is to outline the early attempts to produce metallic zinc in Canada and to trace the gradual development of these first efforts into a viable zinc industry based on modern science and technology.

Jan 1, 1999