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By P. Conrad

Experience has shown that, since the passage of the Surface Mining Control and Reclamation Act, over-compaction of spoil during the reclamation process has severely limited tree growth on reclaimed land. Researchers at the University of Kentucky have conducted a ten-year investigation at a surface mine in eastern Kentucky that monitored the changes in selected spoil physical characteristics for various reclamation and compaction alleviation methods. More specifically, research plots were developed for reforestation that employed three different levels of compaction and two different methods of ripping for overly compacted spoil. Each year measurements were made in the field of dry bulk density, using a nuclear density gage, and maximum penetration depth, using a recording cone penetrometer. In addition to good correlation between tree growth and selected spoil characteristics, the data demonstrated a gradual convergence of the measured spoil characteristic data over the study period.

Jan 1, 2008

Mine planners must select a single pit for design with the knowledge that the grades on which this selection is made are uncertain. This uncertainty is often ignored through the use of deterministic models of grade. This makes the mine planner?s job simpler but does not necessarily lead to the ?correct? or ?best? selection. Grade uncertainty is typically modelled with conditional simulation which generates multiple possible realisations of grade that are equally probable (or improbable) to occur. Methods for incorporating grade uncertainty into mine planning to date have either been perceived as being too complicated, not accessible or too time consuming. This paper proposes a simple and efficient modelling approach to incorporating conditional simulation into pit optimisation, which would be able to be applied in currently commercially software. An example for Resolute Mining Ltd?s Syama Gold Project in Mali shows the range of ore, grade and value outcomes associated with generating pits through a variety of methods.

Feb 27, 2013

By FRANKM. SEIBERT, G. G. Oberfell, GEORGEA. BURRELL

The Bureau of Mines is conducting a series of investigations with the common aim of minimizing the losses that occur in the mining and treatment of mineral substances. The results of the investi- gations are being published in reports of the bureau. This report treats of a method of preventing some of the waste of the natural gas incidental to oil mining. This method, the condensation of gasoline from natural gas, offers to the oil operator and others a profitable means of utilizing some of the oil-well gas now being wasted. The most desired constituent of crude oil is obtained, the production of oil is not hindered, and the gas, after the extraction of gasoline, can be returned to the leased area to drive pumps or into pipe lines for uses to which natural gas is ordinarily put, usually with its fuel value lessened only in slight degree. Publications already issued briefly discuss the subject. In this report the work is treated in greater detail, and the results of many additional tests are shown.

Jan 1, 1915

By A. C. Fieldner

Much activity is called for in the present period of hightened national effort, and wise direction of such a program must always be conditioned by positive knowledge gained in years of slow and painstaking study and development. Research and technologic investigations on coal by the Bureau of Mines have been described in a series of annual

Jan 1, 1941

This publication contains 10 papers presented at a symposium on ATRS systems in Charleston, WV, on June 23, 1983. Included are papers by MSHA Technical Support (Roof Control), West Virginia Institute of Technology, the Bureau of Mines, and seven roof bolter manufacturers and/or designers of ATRS systems. These papers summarize the most recent developments in ATRS technology and can serve as a guide to potential designers, developers, and users of ATRS systems.

Jan 1, 1985

In 2006, a total of 4,573 stone mining operations reported employment to the Mine Safety and Health Administration (MSHA).1 Stone mines comprised 30.7% of all mining operations. ? Mines producing the primary commodity of limestone (crushed and broken) comprised the largest number of operations (n=2,042; 44.7%). ? Stone mining operations were located in all states and territories except Delaware and North Dakota. ? Pennsylvania had the most stone mines (n=368; 8.0%), followed by Texas (n=342; 7.5%).

Jan 1, 2008

By M. Botz

For leach solutions containing primarily free cyanide, the silver nitrate titration method is a rapid and acceptably accurate means of analyzing for cyanide. However, in leach solutions containing elevated levels of copper, the titrimetric method significantly over-estimates the concentration of free cyanide and under-estimates the concentration of weak and dissociable (WAD) cyanide. The authors have developed a modified potentiometric titration method for determining WAD cyanide that overcomes issues with high copper levels in solution. The new MP-WAD method involves addition of a chemical ligand to the sample prior to silver nitrate titration to fully release cyanide bound to copper. Once released from copper, cyanide in solution is no longer affected by the presence of copper and titration results are quantitative rather than empirical. In multiple laboratory trials with synthetic solutions and complex actual leach solutions, accurate WAD cyanide measurements were achieved using the MP-WAD method. Analyses obtained with the new method were found to be within about ±10% of analyses obtained with the USEPA OIA-1677 WAD cyanide analytical method.

Feb 27, 2013

By Edith Lafontaine

Modern underground mines operate fleets of mobile production equipment including drill jumbos, long-hole drills, load-haul-dump machines, trucks and bolters. Their availability has a substantial impact onto production cost and thus onto mine profitability. Through appropriate collection of pertinent data and information, use of adequate performance measures and their analyses, mine operators can identify the most promising and cost effective opportunities to get more from their equipment and to reduce the overall cost. This paper presents results of the study aimed to review and analyse means and measures used to quantify equipment availability and its contributing factors (reliability, maintainability and maintenance support) in several Canadian underground mines. It overviews current reporting procedures, sources, quality and quantity of the data and information collected as well as examines performance measures and their definitions used by the surveyed mines. Problems concerning data acquisition as well as meaningfulness and usefulness of the above mentioned metrics are also discussed. The paper concludes with some suggestions and recommendations concerning several aspects of equipment availability assessment. It is believed that the latter may become a more useful tool for mine operators in their efforts to reduce production cost than it seems to be the case at present.

May 1, 2007

By W. W. Weller

Thermodynamic values for scandium and its compounds are very sparse. This is evident upon examination of any of the commonly used compilations of thermodynamic data. For example, National Bureau of Standards Circular 5004 lists only four heat of formation values, two free energy of formation values, and four heat-capacity values for scandium compounds. The entropy of crystalline scandium is one of the most fundamental values that has been lacking. This Bureau of Mines paper reports heat-capacity data for scandium metal in the temperature range from 50° to 298° K., together with the entropy value at 298.15° K. derived from these data through application of the third law of thermodynamics.

Jan 1, 1962

By D. R. Babich, E. R. Bauer

Noise-induced hearing loss (NIHL) in mine workers, especially underground coal miners, continues to be a problem in the mining industry. The recently enacted MSHA noise standard, Part 62 – Occupational Noise Exposure (Federal Register, 1999), is aimed at reducing NIHL in the mining industry. The U.S. National Institute for Occupational Safety and Health (NIOSH) is conducting a cross-sectional survey of noise sources and worker noise exposures to address NIHL in various aspects of coal mining including surface mining, coal preparation plants and underground mining. In underground bituminous coal mining, noise surveys, consisting of full-shift worker noise exposure, time-motion studies and equipment noise profiling, have been completed on longwall and continuous miner sections in six underground coal mines. The studies revealed widely varying shift-to-shift worker exposures, with workers in certain occupations routinely exposed to potentially hazardous levels of noise. A summary of these studies is reported, including worker dose, source/dose relationships and equipment noise profiles.

By THOMAS LEONBRD WATSON

I. INTRODUCTION. THE results embodied in this paper are based on a careful field- and laboratory-study of the lead- and zinc-deposits of the Virginia-Tennessee district, begun in the latter part of the summer of 1904 and completed in the spring of 1905, preparatory to the publishing of a State report .on them. A separate description of the individual deposits in Virginia is purposely omitted, since I have already described them in considerable detail in a State report. The Tennessee deposits are described here in some detail for the reason that no detailed record of them has yet been published. Practically, this paper summarizes the results obtained from a study of the geology of the ore-deposits of the district as, a whole. (I had the pleasure of visiting the deposits of Virginia and Tennessee with Dr. H. Foster Bain of the U. S. Geological Survey, in April, 1905. Figs. 21 and 22 are from photographs taken by Dr., Bail.) II. HISTORICAL. . The first authentic records of lead-mining .in Virginia date hack more than 150 years; and the old lead-mines at Austinville, on New river in Wythe county, V a., were the first to be worked. Colonel Chiswell, a native of Wales, and one of the earlier adventurers in southwestern Virginia, was one of the first operators of the Austinville mines. Chiswell's operations at Austinville commenced in the year 1750, and closed shortly after the beginning of the Revolutionary War, in the' year 1776, covering a period of about 25 years. From that time to the present, mining has been carried on almost continuously in the Virginia area. For many years after the Virginia mines were operated, mining was confined exclusively to the lead-ores. The zinc-ores

Mar 1, 1906

By Y Xie, D Willingham

Predictive maintenance (also known as ‘condition/health monitoring’) refers to the intelligent monitoring of equipment to avoid future failures. In contrast to conventional preventive maintenance, the maintenance schedule is not determined by a prescribed timeline; instead, it is determined by analytic algorithms, such as machine learning, using data collected from equipment sensors and/or via simulation.Predictive maintenance offers the following benefits for operators and equipment manufacturers:- reduces equipment downtime by identifying issues before failure, thereby enabling convenient scheduling of equipment service and extending equipment lifetime- determines the root cause of the failure, enabling appropriate service to be performed without utilising resources to determine a diagnosis- avoids the unnecessary costs of maintenance and unexpected failures- improves safety and product quality.Algorithms and data are critical to predictive maintenance success. Sensor data is first preprocessed using advanced statistical and signal processing techniques; it is then combined with predictive modelling techniques, such as machine learning, to estimate equipment health.Once tested, predictive maintenance algorithms may be used in an operational setting within an IT environment, such as a server or cloud. Alternatively, algorithms may be implemented in an embedded system directly on the equipment, allowing for faster response times and significantly reducing the amount of data sent over the network.CITATION:Willingham, D and Xie, Y, 2017. Predictive maintenance modelling for bearing-based equipment, in Proceedings Iron Ore 2017, pp 627–630 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Greg Parker

"As the Explosives Industry continues to evolve and condense, those involved, such as Blasters,Contractors, Distributors and Consultants, continue to be challenged by both internal and externalforces. Increased pressure by government agencies, higher safety standards, new levels of technology and mandatory certification programs, are forcing us to expand our awareness and increase our levels of efficiency. These higher standards require increased awareness. Increased awareness requires better training programs and better supervision with emphasis on production and the employee. This means the desire to improve must be instilled from the top down. this paper will explore the current impediments to this goal and discuss the possible solutions for achieving greater safety awareness, increased production and higher levels of personal achievement. Through the use of audio/visual aids, I will attempt to show the discrepancies as well as the solutions."

Jan 1, 1999

By D. Bessinger

The present paper provides a brief overview of the thermodynamics of titania rich slags, an outline of the Multi-Phase Equilibrium (MPE) package and its application to ilmenite smelting. Through assessment of published experimental data on various systems containing TiOx, it was found that despite considerable scatter in measured phase equilibria data for the binary Ti2O3-TiO2system,the behaviour of binary and higher order titania rich slags and oxide solid solutions phases could be represented by solution models in the MPE package. Results from the applications of the MPE model on the stability of solid phases and slag-refractory interactions will be presented and discussed. Parallels will be drawn between the predictions by the model and observations made during pilot plant tests. Key words: Thermodynamics, titania slags, ilmenite smelting, phase equilibria, refractory.

Jan 1, 2003

By V. Yahorava

Ion exchange is considered to be an effective technology for the removal of various impurities from cobalt advance electrolytes. With the correct choice of resin, ion exchange can consistently remove the required impurities to the levels for the production of high-grade cobalt metal. Although ion exchange was in the past used primarily for nickel removal, more recently it has been also considered for the removal of copper, zinc, and cadmium. Generally, granular ion exchange products are used, but Mintek is currently evaluating ion exchange fibres for a number of applications, including the removal of copper from cobalt advance electrolytes. Fibrous ion exchangers have major advantages compared to granular resins in that they have significantly higher reaction rates, and wash water volumes could be limited. Granular and fibrous ion exchangers were evaluated and compared for the removal of copper from cobalt advance electrolyte. A synthetic electrolyte containing 50 g/L cobalt and 50 mg/L copper was used for the test work. Equilibrium isotherms, mini-column tests, and split elution tests were done. The results were used to size a full-scale operation to treat 100 m3/h of electrolyte. The potential cobalt losses or recycle requirements were estimated, and data to calculate indicative operating costs for each adsorbent was generated. This information was used for a techno-economic comparison of granular and fibrous ion exchange systems for the removal of copper from cobalt advance electrolyte.

Jan 1, 2014

By K. A. Larsen, J. L. Ariail, C. M. LaRosa

This article discusses the evolution of U.S. laws and policies towards environmental remediation at mine lands over the last 20years, the opportunities that these changes present for reuse, and the remaining challenges associated with community capacity for effective reuse planning and implementation. Emerging initiatives by the U.S. Environmental Protection Agency and Department of Interior for addressing these challenges are discussed.

Jan 1, 2004

By S. Kittel, P. Galleguillos, H. E. Urtubia

The rougher flotation at Escondida consists of 80 cells of 100 m3 each, with injected air. Escondida has developed a system of automatic control of the rougher flotation using video cameras, which have been operating since 1997 for remote monitoring and manual control. Since 1999, an image processing software and a group of rules have allowed implementation of an expert system. To date, the expert system controls the superficial speed of each cell by adjusting the air flow and the froth depth of the flotation bank. Preliminary tests of the expert control on two of the eight rows gave 1.2% higher rougher recovery at a 92% degree of confidence. The proven benefits are already sufficient to move towards a complete plant implementation.

Jan 1, 2001

Mine planning includes equipment selection as a subprocess because aging equipment must be replaced to maintain or improve productivity levels. The criteria used for decision-making in mine planning and equipment selection are often inextricably linked and inherently contradictory. For example, financial wisdom demands that development, which is an expense and locks up capital, be deferred as far into the future as possible yet on the contrary technical knowledge suggests that developing well ahead of stoping is practically desirable because it generates additional geological information required to improve planning of the unmined portion of the orebody and create better operating flexibility. Consequently, mine planning professionals have to delicately balance all decision criteria when executing mine planning in order to achieve optimal mineral extraction or when selecting equipment, so that capital is optimally deployed. These two processes can therefore be characterised as belonging to the multi-criteria decision analysis (MCDA) type of problems. MCDA problems are alternatively referred to as multiple attribute decision-making (MADM) problems and belong to a broader group of problems called multi-criteria decision-making (MCDM). There is now a gradual recognition and application of MCDA techniques in the minerals industry. This paper explores the theory, current and potential application of these techniques in decision-making in the minerals industry.

Dec 6, 2010

By Bruce Geller

The 2004 Prospectors and Developers Association of Canada (PDAC) conference contained an air of optimism and excitement that has not been seen since 1997. Many segments of the mining industry are alive and well. This is largely a reflection of improved metal prices, themselves due to the strong euro and improvements in Asian economies. Those factors offset higher oil prices, a weaker U.S. dollar and concerns about the Middle East. This report is an overview of the conference. It is supplemented by an examination of conference handouts, abstracts and a few complete papers that are on the PDAC’s Web site www.pdac.ca. Sixty PDAC 2004 abstracts are available at the same site, along with 15 complete papers in PDF format. The conference was held March 7-10 in Toronto, Ontario. It was attended by a record 9,200 delegates from 85 countries. About 8,000 people from 74 countries attended the 2003 conference.

Jan 1, 2004

By Martin D. Conyac

Results of the minerals survey indicate low potential for the discovery of placer gold along Deck Creek aid for copper, silver, and gold in PreTertiary rocks within the boundaries of the Lake Fork RARE II area. Potential for oil, natural gas, coal, and geothermal resources is negligible. No evidence of economic mineral resources was found during the examination of the study area, and no assays of rock or placer samples taken from the urea showed economic mineral values. There are no producing or developing mines within the boundaries o of the lake Fork study area. SETTING Mining Districts The Lake Fork RARE II area is on the eastern fringe of the Cornucopia Mining District, which is centered about 6 mi west. It is also on the western edge of the Homestead district, centered about mi east.

Jan 1, 1983