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By Roger C. Ilsley

The $2.1 billion Milwaukee Water Pollution Abatement Program (MWAP) requires the construction of several miles of underground openings at depths up to 350 feet for the conveyance and storage of sewage and storm water overflows. The system will include approximately 27km (17 miles) of deep tunnels ranging from 3m (10 f t.) to 9m (30 f t.) in diameter, 26 shafts and a pumping station cavern. The facilities will be located primarily in Silurian Age dolomites of the Niagara Group. The rock is characterized as competent with vertical to sub-vertical orthogonal jointing and predominantly thin shale bedding planes. The site investigation was carried out incrementally, commencing on an area wide basis, becoming site specific as facility plans were developed. To achieve cost savings through uniformity and continuity, a computerized data bank was established. Software was developed during the initial stages of the program for the production of borehole logs, structure contour maps, geologic profiles and summaries of data for statistical evaluations. This paper discusses in general terms the collection, compilation and presentation of data necessary for the characterization of the rock mass.

Jan 1, 1984

By M. E. Tyrrell

Lightweight basic refractories suitable for use in some sections of the all-basic furnace were developed. Potential advantages of such refractories are lower weight, improved resistance to thermal shock, and less tendency to spall off the working face. Plant trials in positions not subject to heavy loading or severe erosion seem warranted. Forsterite (2MgO.SiO2), stabilized dolomite (2Ca0?SiO2 + MgO), and chrome-spinel [(Fe,Mg)0?(Cr,Al) 031 refractories were fabricated using bubbles as the principal component in the brick mixtures. Bubbles were blown from melts of the basic raw materials as they were tapped from a conducting-hearth arc-resistance furnace. The bubbles were graded, bonded with synthetic Forsterite plus mineralizers, dry-pressed, and fired to temperatures of 1,600° C. or over in a gas-fired kiln. Refractory properties of the bubble brick were compared with those of insulating refractories made by burning combustibles out or dense brick mixtures. Lightweight refractories fabricated of bubbles were one-third lighter in weight than dense bricks of like materials. Their mechanical strength was satisfactory, and their resistance to thermal shock was excellent. In tolerance to open-hearth slag and in resistance to thermal shock, the chrome-spinel bubble bricks wore the best of the refractories tested. Basic refractories of the insulating type were about 40 percent lighter in weight than dense commercial refractories, but they were mechanically weak and not suitable for superduty service.

Jan 1, 1962

By Robert W. Geehan

"INTRODUCTION The Bureau of Mines, in cooperation with the Federal Geological Survey, explored the Crowell fluorite mine by core drilling in 1945. Claims investigated are in sec. 14, T. 12 S. R. 47 E., M. D. B. & M., in southern rye County, Nev., about 5 miles east of 'Beatty.The twelve holes drilled by the Bureau totaled 3,661 feet. During 1945 the mine operator drove extensive exploration drifts, in part to verify results of the Bureau's work. The drilling program was designed to test for extensions of ore bodies known in the mine.The Crowell mine has shipped Ore to steel plants on the west coast for the past 20 years. During the war this market called for all the fluorite the mine could produce, but previously there were periods when it was difficult to sell ore or concentrates.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Nines 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.Special acknowledgment is due to Glenn Allen, district engineer;A. C. Johnson, chief, Reno Division, Mining Branch; S. R Zimmerley, chief, Salt Lake City Division, Metallurgical Branch; W. R. Thurston of the Federal Geological Survey for advice on geological problems; and J. Irving Crowell, Jr., operator of the property, for his cooperation."

Nov 1, 1946

By J. P. Morris

An experimental blast furnace in normal operation was quenched by substituting cold nitrogen for the hot blast air. More than 2,200 samples from the stack, bosh, and hearth were taken; 500 of these were selected for detailed analysis. Deductions are made as to the patterns of burden movement and gas flow; the reduction of iron oxides, including a comparison of ore and sinter; and the behavior of sulfur above the smelting zone. Metal and slag beads from the bosh were analyzed, as were samples from the hearth metal and slag. A brief description of a petrographic examination of the quenched burden is included.

Jan 1, 1963

The National Institute for Occupational Safety and Health (NIOSH) conducted a study to determine the effectiveness of a filtered air delivery system to reduce respirable dust exposure to roof bolter operators in underground coal mines. When performing roof bolting operations, roof bolter operators may experience exposure to high levels of respirable dust during a working shift, especially when working downwind of the continuous mining machine. While drilling and installing roof bolts, this filtered air system supplies a clean curtain of air over the roof bolter operator by means of a plenum mounted beneath the canopy. This experimentally designed air curtain, adapted for roof bolting machines used in this study, is based upon previous design prototypes, computational fluid dynamics (CFD) simulations, and trial-and-error testing. Both prototype and final designs were tested in the full-scale mining galleries at the Office of Mine Safety and Health Research (OMSHR) in Pittsburgh before being taken underground for field testing. Test results of the system in both laboratory and field studies show reductions in operator exposure to respirable dust when the operator is positioned directly under the protected zone of the canopy.

Jan 1, 2012

By S Hapugoda, A Poliakov, E Donskoi, L Lu

A significant amount of metallic iron in the world is produced in blast furnaces from iron ore pellets. To control the quality of pellets and to optimise pellet production, characterisation of both green and fired pellets is required. Optical image analysis (OIA) allows identification of different minerals, binder, remaining fluxes and porosity within pellets.For proper identification of the mineralogy, porosity and texture in pellets a high magnification is required, therefore each individual image covers only a very small portion of the pellet. At the same time the characterisation of pellets requires that the whole pellet is represented as a single object, so the size of the resulting overall image at high magnification can make it difficult to handle. A solution to this problem has been implemented within the CSIRO OIA package Mineral4 by combining images at different levels. Namely, to average out local irregularities, individual frames can be stitched during imaging into larger MosaiX images. Mineral4 further combines these MosaiX images into a single panorama image of the whole pellet.The proposed procedures allow the calculation of mineral and porosity spatial distributions, local gradients and abundance graphs based on the distance from the centre of the pellet. The ‘Pellets’ module of CSIRO OIA software also allows for characterisation of large irregularly shaped particles of lump ore and sinter.CITATION:Poliakov, A, Donskoi, E, Hapugoda, S and Lu, L, 2017. Optical image analysis of iron ore pellets and lumps using CSIRO software Mineral/Recognition, in Proceedings Iron Ore 2017, pp 583–592 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

Utilizing a very large database from a mined-out area on a South African gold mine, the relative efficacy of a method to mitigate the smoothing effect introduced by the algorithmic constraints imposed by kriging was investigated. Smoothing effects arising from limited data availability are differentiated from the smoothing arising from the application of estimation algorithms. Very little can be done to ameliorate smoothing of estimates because of too little data, barring additional drilling or sampling. However, the smoothing effects resulting from the kriging process are shown to be mitigated by use of an alternative algorithm. The primary criterion in the development of the new algorithm was to avoid re-introducing conditional bias. This paper examines firstly the smoothing effects introduced into estimates via the kriging covariance matrix, secondly the process for ameliorating the smoothing effect, and finally it uses a case study to demonstrate the effectiveness of the new algorithm on a very large database. The database was used to introduce a 60 m by 60 m drilling pattern which in turn was used to model the semi-variogram and produce 30 m by 30 m kriged block estimates. The follow-up database was then re-introduced (roughly 5 m by 5 m grid spacing) and averaged into 30 m by 30 m blocks to provide a direct comparison with the initial estimates. In this way the extent of smoothing and accuracy of the estimates before and after the corrections was tested.

Jan 1, 2014

By Vincent Roy

Numerous on going activities at the Daniel-Johnson Dam : ? Surveillance / monitoring ; ? Structural investigations & evaluation ; ? Injection work ; ? Crack mapping ; ? Instrumentation management (drawings & inventory) ; ? Drainage system state ; ? Foundation evaluation

Aug 1, 2013

By J. D. T. Capocchi, M. B. Mourao

The rate of reaction between iron oxides and carbonaceous materials, agglomerated as pellets, was studied experimentally by measuring the weight loss as a function of time. The effects of temperature, carbon type, inert gas flow rate, pellet size and additions (sodium. carbonate and Portland cement) were determined. It was shown that the value of the apparent activation energy can display large deviations under different experimental conditions; in the present work it was found to be 226.6 kJ/mol. The reaction with coke is slower than with charcoal, and the rate increases as the flow of inert gas in the reaction vessel decreases. Comparison of the rates for pellets of different sizes has shown that for small pellets the initial rate is faster but that it slows down at high conversions owing to the penetration of inert gas into the pellet. Additions of sodium carbonate and Portland cement increase the rate; sodium. carbonate promotes the catalysis of the Boudouard reaction, which is the slowest of the partial reactions. The increase in the rate with Portland cement is attributed to the release of water vapour

Jun 18, 1905

By C E. Davies

At present the source of virgin iron for steel produced in New Zealand is titanomagnetite extracted from titaniferous beachsands. Some of these beachsand deposits contain extractable quantities of ilmenite as well as titanomagnetite and both minerals represent challenging sources of vanadium and titanium products in addition to iron. This study looks at some theoretical aspects of smelting these ores directly with coal rather than with electric power, and takes into consideration the properties of the raw materials, the thermodynamics of possible process routes and the background of the economics involved.

Jan 1, 1980

By Lucien P. Weber

Over the last few years, increased customer demands as well as strong competition from substitute materials have accelerated the development of advanced technologies to improve both the performance and the cost-effectiveness of steel H-piles. On the material side, the development of an in-line heat treatment, combined with the most advanced steelmaking and rolling techniques, allowed to create a new generation of high-strength low-alloy steel grades, called HISTAR, achieving yield points up to 500 MPa (~72 ksi) and yet maintaining excellent weldability properties thanks to a low carbon equivalent. The topic of this paper is to illustrate the performance of H-bearing piles in HISTAR steel grades. In 1989, a major test program was started at different locations in Hong Kong, which is renowned for its difficult soil and severe driving conditions. After the successful completion of these tests, the HISTAR bearing piles were accepted by the local building authorities. Thanks to their cost-effectiveness, the HISTAR bearing piles have subsequently been used with great success in areas with appropriate soil conditions, especially in Asia and more recently in Europe.

Jan 1, 1997

Our ultimate resources come from the Sun and the Earth System. At this time we face a world crisis in energy, water and soil resources. Global pollution problems are increasing in almost all nations. There is an urgent need to use our vast knowledge with a new wisdom and this requires new integrated teams of experts to provide the best alternatives for the needed new development problems. These teams must include economists, engineers and a broad spectrum of scientists. Today it is possible to produce clean energy, stop soil erosion, clean water and reduce and use wastes of many types.   There is a great need to improve science, natural science, education at all levels. All people must know how our planet works and that fluctuations, some inevitable, some controllable, are inevitable and that we must prepare for them. And it is clear that protecting the environment, eliminating pollution, preserving bio diversity is good economics. Ecology Economy cannot be separated.  

Jan 1, 1995

This work presents: 1.) the results obtained from measurements of temperature profiles in pillars and at working faces of three coal mines located in Colorado and New Mexico, 2) a comparison of the experimental results with theoretical predictors based on linear heat flow models, and 3) temperature profile predictions based on a two dimensional coal mine model with an inclined crack located in the roof or wall of the opening. The thermal properties of the coal and shale samples taken from the mines were used as input data for the computer model. Good agreement was found between the measured profiles and the theoretical values obtained with the one dimensional model. The two dimensional model results show that a visible crack (0.01-0.07-ft thick) in a coal roof causes a surface temperature difference from 0.2 to 1°F at the edge of the crack for rock exposed to air from 1 hr to 288 hrs and with the air to rock temperature differences from 2°-6°F. A temperature difference of 0.3 °F was found between solid and broken rock in a shale roof with a 0.03-ft thick crack inclined 45° to the horizontal after a ventilating time of 48 hrs and the air to rock temperature difference of 2.1°F.

Jan 1, 1972

Simulator technology has advanced to the point where the cost of mining equipment simulators is beginning to make commercial sense. Simulator-based evaluation allows operators or potential employees to be assessed in a pseudo-real environment under surface and underground mining conditions. Simulator training also allows operators to be exposed to emergency and advanced situations such as brake or steering failure or a tireblowout. ThoroughTec, of South Africa, provides simulator equipment to the mining industry. The company’s various packages of simulator products provide an unbiased evaluation score that removes human error from the assessment process. This same evaluation score is also presented at the end of normal training or refresher training sessions. In this way, the simulator helps eliminate bad habits and improve efficiencies.

Jan 1, 2003

By Peter Murphy

This report (arid related appendices) provides a description of the functional design specifications, engineering design specifications, and program of instruction for development of a training system for dragline equipment operators. Based upon a task analysis and training system analysis prepared under Phase I, Phase II efforts expanded upon and refined the functional design specifications. The training hardware components have been developed to a point shy of system fabrication. A detailed outline of the porgram of instruction and content sequence has been prepared. The objective of the training system described in this report is to provide new operators of dragline equipment with the requisite skills and knowledge to assure cost-effective development and an adequate supply of our human resources.

Jan 1, 1976

The Bureau of Mines is responsible for a broad spectrum of programs for meeting the diverse and changing mineral resource needs of the Nation. These programs are managed by the Director and two Deputy Directors, who formulate general policy and program direction from the Washington, D.C., headquarters. A senior advisory staff, consisting of the Chief Staff Officer, Chief Scientist, and Chief Mining Engineer, provides advice and consultation to the Director on a wide range of scientific and technical matters and acts on behalf of the Director to maintain liaisons with other government agencies, mineral industries, and professional societies. Bureau program activities are classified into two major functions: (1) Developing new and improved technology that will make the production and processing of minerals more efficient, safer and more healthful for mineral workers and the public, and more compatible with a quality environment.

Jan 1, 1980

The concentration of Mt. Morgan sulphide ore has always been attended by serious loss of gold. Until recently, with a simple selective flotation flowsheet, even the lowest grade of ore milled-about 2 dwt. per long ton-thislloss was 0·9 dwt., whilst for average to high-grade ore, 3·5 to 5 dwt., the figure was 1·5 to 2·0 dwt. Early in 1937 it was decided to equip the research laboratory for an investigation into the condition and location of the escaping gold and the physical and mineralogical barriers preventing its recovery.With the completion of: this equipment in July 1937, trial and error testing, which had been explored to exhaustion, was abandoned and a five months' research programme mapped out and commenced. Based on the knowledge so gained, a flowsheet combining primary desliming, bulk flotation of the natural slime, selective flotation of the deslimed fraction, and cyanidation of the selective flotation tailing was drafted and tried with encouraging results in a 70-lb. per hour pilot plant. This flowsheet, modified to meet current circumstances, is being dove-tailed into the existing 1,500-ton sulphide ore concentrator, though the cyanidation treatment is actually carried out in the oxidized ore mill, to which the flotation tails are pumped.RESEARCH EQUIPMENT(1) Five tube elutriator (Fig. 1) t built in the company's workshop.

Jan 1, 1939

By Wm. A. Haven

ON the northern part of the globe, almost since the earliest days of mankind's history. ironmaking has been practiced in one form or another. Some investigators question the generally accepted belief that copper and bronze were in earlier general use than iron, explaining the greater age and abundance of copper relics by their greater resistance to natural oxidation. However, the occurrence of copper in its natural state and its greater ease of reduction from the simpler copper minerals is a strong argument that the making and use of copper came first. Nevertheless, good evidence exists that ironmaking was practiced in ancient India and China, as well as in ancient European countries. Some interesting vestiges of those early operations still survive and have a place, in the background at least, of a discussion of modern blast-furnace practice.

Jan 1, 1940

By Charolett Hayes, A. L. Russell, Anthony J. Bednar, Jared Smith, Valentine A. Nzengung, Stephen L. Pilcher

The manufacture of Energetics Materials (EM), including maintenance and demilitarization of munitions causes dangerously high levels of explosives residues to be harbored in building features. The two commonly approved methods of decontaminating energetics contaminated equipment and building features are thermal treatment and steam washing. The current regulatory environment is generally becoming more stringent and unfavorable to thermal and steam decontamination because of their adverse impact on air, soil, and water and their ineffectiveness to completely remove accumulated energetics from foundation cracks, internal and external piping, voids in walls and ventilation systems, and internal cavities of fixed equipment. However, chemical destruction of energetics, especially high explosives, is gaining acceptance as a safer, cost-effective and environmental friendly alternative to thermal and steam decontamination. Organic explosives, including nitramines and nitrate esters are oxidized organic compounds that are susceptible to chemical oxidation and reduction reactions. Under suitable conditions, a chemical reagent consisting of sulfur-based bulk reductants (neutralent) commercialized as MuniRem generates highly reactive free radicals that very rapidly degrade many energetic compounds to innocuous end products while stabilizing metals as the insoluble metal sulfides.

Jan 1, 2016

By Staff

The mineral sector is a fundamental part of the U.S. economy. It contributes to the real gross domestic product (GDP) at several stages—basic (mining), intermediate processing, manufacturing of finished goods and construction. The estimated growth rate for the real GDP of the United States for 2006 was 3.2 percent. The nominal GDP was about $13.2 trillion. The value of minerals mined in the United States in 2006 rose significantly because of increased unit price for some metals—particularly copper, zinc and other base metals. There was also a significant reduction in metals stocks. Infrastructure expansion and manufacturing in China and India have been absorbing a significant portion of world output. Domestic production increased for some industrial mineral materials, mainly cement and construction sand and gravel. Production of crushed stone declined less than 1 percent in 2006 compared

Jan 1, 2007