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By Walter T. Lewieki

"INTRODUCTION Numerous deposits of iron ore are found in Cherokee, Bartow, Floyd, and Polk Counties in northwest Georgia. The deposits are generally small and irregular in shape. The ore is usually referred to as ""brown ore"" and is predominately limonite. The crude or ""bank ore"" has to be washed and concentrated before being shipped.The proximity of the deposits to the Birmingham furnaces and a favorable freight differential permit the operation of many deposits that otherwise would be uneconomical. The district produced 413,468 long tons of brown-ore concentrates, averaging 45.53 percent iron in 1943.The necessity of developing additional iron-ore reserves for the war energeucy to supplement the production of the Birmingham district, prompted the Bureau of Mines to initiate exploration of the more promising northwest Georgia deposits. Thirteen properties in the four counties were explored during the program (fig. 1).HISTORY AND PRODUCTIONSeveral furnaces were operated in the district until the early 1900's, ranging from charcoal furnaces to more modern plants with capacities up to 50 tons of pig iron. No furnaces have operated for about 40 years, the product being shipped to Alabama and Tennessee.Bartow County iron mining is declining, although formerly it was the principal producer of the district. Most of the known merchantable ore deposits have been exhausted. For the past 3 years the Mitchell-Hodge mine has annually produced about 225,000 long tons of concentrates containing 46 to 43 percent iron and at present is the only large producer in Bartow County."

Jan 1, 1946

By Wilder H. Brinton

"INTRODUCTION The Queen Mary copper property is in sec. 18, T. 12 N., R. 16 W., in the Clinton mining district of Missoula County, Mont. It was examined by an engineer 3/ of the Bureau of Mines, November 21, 1943. Upon the basis of his recommendations, a small trenching and diamond-drilling program was begun November 11, 1944. One diamond-drill hole was completed December 16, -944, but because of frozen ground trenching was postponed until June 1945 and then completed. This report describes the results of exploration.ACKNOWLEDGMENTSIn 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, analyses samples and performs beneficiation tests. Both of these branthes are under the supervision of Dr. R. S. Dean, assistant director.The chemical analyses included in this report were made at Reno, Nev., under the direction of A.C. Rice, acting engineer in charge. Rare and Precious Metals Experiment Station, Bureau of Mines."

Nov 1, 1946

By F. E. Walker

The Bureau of Mines determined total sulfur and sulfur forms for coal in 283 counties in 29 States and 2 fields of the State of Alaska. Specifically, organic, pyritic, and sulfate sulfur were measured of approximately 2,900 samples, and they include most of the coalbeds in the United States.

Jan 1, 1966

By F. E. Walker

The Bureau of Mines determined total sulfur and sulfur forms for coal in 283 counties in 29 States and 2 fields of the State of Alaska. Specifically, organic, pyritic, and sulfate sulfur were measured of approximately 2,900 samples, and they include most of the coalbeds in the United States.

Jan 1, 1966

By J Knoblauch, D, P J. J Strobos, C Foggo

The Sally Malay Project is located 120 km north of Halls Creek in the eastern Kimberley region. Since commissioning, ongoing improvements on the plant have resulted in recoveries now greatly exceeding the initial design targets. The continual optimisation endeavours of the Sally Malay metallurgy department included an automation project that was done in close collaboration with Mintek. In this team effort, several problem areas were addressed and the FloatStar advance control system was successfully commissioned to stabilise and optimise the flotation circuit. The remote location of the Kimberley Nickel Mines operation, fly-in, fly-out roster and the current mining boom makes the acquisition of experienced flotation staff difficult. The implementation of an automated flotation control system reduces this burden and contributes to the training of inexperienced staff. This paper illustrates not only the process control improvements achieved as a result of the installation of the FloatStarÖ advanced control system, but also how it has assisted operational personnel with their understanding of the process.

Jan 1, 2006

Discussion following the presentation at the North of England Institute of Mining and Mechanical Engineers' general meeting held in Newcastle-upon-Tyne, 8th April 1916, included the author's introduction, written contributions by Bedson P.P., Gregory T.W.D. and Morgan J.D., oral contributions by Louis H., Greener T.Y. and Severs W., and the author's reply

Dec 1, 1916

By Theodore H. Eyde

In 1971, the Minerals Division of The Superior Oil Company acquired exploration rights to an unpatented claim group in the Superior (Pioneer), Arizona mining district, lying west of the Concentrator fault. This major post-mineral fault displaces the Magma vein-fault, which is mined in the Magma Mine at Superior, Arizona. The Magma vein-fault and the enclosing section of pre-mineral rocks consisting of Paleozoic and younger Precambrian sediments and diabase, is overlain by a thick section of post-mineral rocks, consisting of the Gila conglomerate, the Apache Leap dacite, and the Whitetail conglomerate. Geologic information on the thickness and attitudes of the rocks obtained from previous diamond drilling indicated that the section of post-mineral rocks might be from 3,000 to over 4,010 feet thick in the target area. (Figure 1) The Magma vein-fault is a steeply dipping vein which has produced nearly a billion dollars of copper, zinc, silver, and gold. It has been mined continuously for nearly 10,000 feet along the strike and nearly 5,000, feet vertically down the dip. It ranges from less than a foot to over 50 feet wide and contains sulfide mineralization con¬sisting of pyrite, chalcopyrite, bornite, and chalcocite.

Jan 1, 1973

By R. Strydom, J. H. Selby, J. Slabbert, W. Enslin

Zircon is a naturally occurring silicate of zirconium, which is used in large quantities (~1 million tonnes per annum) for its refractory properties and its extreme chemical inertness. All zircons contain uranium and thorium bound into the crystal lattice, generally at levels up to 500 ppm of uranium plus thorium. This paper focuses on one aspect of the zircon industry—the ability to safely transport large quantities of zircon sand. Currently zircon is not classified as a radioactive material for transport purposes. However, this is because of a factor used in the exemption clauses of the IAEA code on safe transport of radioactive materials. The objective of this study was to determine the validity of this factor, and was submitted as part of an IAEA Coordinated Research Project (CRP). The study is based primarily on measured rather than modelled data and covers the transport of large quantities of zircon from producers in South Africa to customers in Europe. Both occupational exposure of workers and exposure of members of the public have been considered. The transport routes studied cover rail, road, ocean-going ship and inland barge transport of unpackaged bulk products. The study showed that the most exposed member of the public would receive 10µSv/annum,while the most exposed worker would receive 144µSv/annum of exposure. It is concluded that these levels are well below all regulatory limits for such activities involving naturally occurring materials. The study also showed that normal operational exposures are higher than those in accident scenarios, a feature which does not occur with higher activity materials. It is further concluded that the study validates the use of the factor of 10 in TS-R-1, as applied to zircon sand. Additionally it is also concluded that the exemption currently applied to the transportation of bulk zircon sand is valid.

Jan 1, 2003

By James Noll

Total carbon (TC) is sometimes used to measure or characterize diesel particulate matter (DPM) in occupational settings such as underground mines. DPM samples are collected on quartz fiber filters. When using quartz fiber ?lters, adsorption of gas phase organic carbon (OC) has been reported, causing a positive bias in the particulate TC results (adsorption artifact). Most of the data on the sampling artifacts and corrections apply to environmental air sampling, where samples are collected at a much higher filter face velocity and the OC concentrations are generally much lower relative to occupational sampling. In this study, we investigated the effects of adsorption artifact on samples from occupational settings. Samples were collected with and without denuders to determine the amount of gas phase OC collected and the accuracy of certain corrections. In underground stone mines, the adsorption artifact was found to positively bias the particulate TC by greater than 20% for filter loadings below 25 µg/cm2 TC (8-h time weighted average) 262 µg/m3). The tandem ?lter correction reduced the effect of the artifact, as high as 60% of the TC value, to less than 11% for laboratory data. It also significantly reduced the effect of the artifact obtained for field samples.

Jan 1, 2008

By H. F. Coward, G. W. Jones

"IntroductionIn the course of an investigation on the influence of black damp (a mix of nitrogen and carbon dioxide) on the limits of inflammability of fire damp (methane) in air, some new information was obtained concerning the factors that determine whether or not a gas mixture is capable of self-propagation of flame. Volume for volume, carbon dioxide exceeds nitrogen in its extinctive action on flame, an effect which is generally attributed to the higher molecular heat capacity of the former. Argon, a as of lesser heat capacity than either, proved to Lave less extinctive notion. If, as seemed likely, the extinctive action of a chemically inert gas could be attributed entirely to its heat capacity, then helium should behave like argon; equal volumes of these two oases should exhibit equal extinctive action, for their molecular heat capacities are nearly identical at laboratory temperatures and, in all probability, remain constant up to and beyond flame temperatures. The experiments reported here show, however, that helium has proved to be more extinctive of methane flames than argon.Method Used in ExperimentsThe limits of inflammability of methane, in various ""atmospheres"" composed of mixture of air with one or other of the diluent were determined in a vertical glass tube, 6 feet long and 2 inches in diameter. The lower end of the tube was opened by sliding away a ground-glass joint and the flame of a small spirit lamp was immediately passed across the aperture. The tube was sufficiently long to enable observers to judge whether a flame was self-propagation for if a mixture were incapable of continued self-propagation pf flame, the lamp of flame formel above the source of ignition was extinguished within feet of its passage up the tube."

Jun 1, 1926

The contract objective was to evaluate sources of airborne quartz and research control methods that would assist underground mine operators in complying with respirable dust standards which have been reduced because of quartz in the dust exceeding five percent. The work involved: Phase I -evaluate sources of quartz dust at the roof bolter work location; Phase II -evaluate the relationship between the quartz content of the coal and adjoining rock strata and quartz exposure at the roof bolter and continuous miner locations Phase III -conduct laboratory tests to determine performance parameters for roof bolter dust collector systems. The underground surveys for Phases I and II determined: (1) the continuous miner typically is the greatest source of quartz exposure for the miner and roof bolter operators when single-split ventilation is utilized, (2) a statistically significant relationship be­tween quartz content in face material and operator exposure was not determined and data suggested mining equipment and procedures may be more critical. The Phase III lab tests indicated the use of dust hog-type bits, filter cartridges, maximized collector airflow, and reduced bit rpm should be utilized to minimize dust liberation at the roof bolter.

Jan 1, 1985

By H. V. Flagg

OPERATION of a modern steel plant presents a curious anomaly. Large-scale operations, in which large volumes or heavy weights of materials are involved, are not usually subject to close control or narrow specifications. On the other hand, operations that call for a high degree of precision are usually carried out under carefully controlled conditions with delicate, precise machinery and tools, and production is made secondary to quality. In a modern steel mill both extremes are taken as a matter of course. A strip mill making auto-body sheets must supply its customers with sheets that all come within a tolerance of plus or minus 0.003 in. in gauge at any point from side to side or end to end, and without blemishes either of color or surface. Sheets that were considered par excellence as recently as ten years ago could not even find a market today. Such exacting requirements have made necessary a nicety of control that approaches the watchmaker's art. Notwithstanding this necessity for precision, the scale of operation is stupendous.

Jan 1, 1940

By Ralph D. Gift

This report describes a program of research to evaluate methanometry in coal mines. The program commenced by conducting an extensive state-of-the-art survey. Details of the survey are presented which includes a rating of various types of instruments that can be used to detect and record methane gas. Laboratory test data, on mine instruments tested are presented together with results from a computerized statistical analysts.

Jan 1, 1972

This status report contains 39 individual reports on health and safety research projects now being conducted or recently completed by the Bureau of Mines. The Reports on health research cover industrial hygiene, respirable dust, ventilation, noise control, and radiation hazards. The safety research reports cover industrial hazards, ground control, fire and explosion prevention, and methane control. Each report includes background information, a discussion of research progress, and an assessment of each project's current status.

Jan 1, 1979

By F. E. Lathe

RECENT events have emphasized with renewed force the well known fact that war greatly intensifies the demand for certain metals, particularly for iron, copper, and zinc. Any increase in the use of iron and steel, whether in war or peace, is also accompanied by increased consumption of those metals which find their chief application as ferro-alloys, such as nickel, chromium, manganese, molybdenum, tungsten, and vanadium. Further, since high temperatures are essential for the production of all these metals, activity in the metal industry is inevitably accompanied by an insistent demand for refractories. For example, in North American practice the consumption of magnesitic hearth refractories is frequently expressed in pounds per ton of steel. This quantity (not including straight dolomite) ranges on individual plants from about 7 to 12 pounds. When the industry is operating at approximately full capacity, the ratio of refractory to steel tends to increase, since the tonnage of steel produced is recognized as of paramount importance, and this leads to the harder driving of furnaces and less regard for the effect on refractories. It should also be observed that the cost of refractories per ton of metal produced is always so low, in comparison with other items, that it may even increase while the cost of metal per ton is being reduced through more continuous operation and the use of higher temperatures. As one prominent Canadian copper metallurgist has tersely expressed it, he is "not in business to save refractories but to smelt ore". The effect of war demands and of general industrial activity upon the production of basic and neutral refractories is clearly shown in Figure 1, which gives the value of chrome ore and magnesitic-dolomite produced in Canada during the period 1907 to 1937. Tonnages have not been shown, as these are not available for the full period; such figures as have been published from time to time are not strictly comparable, since both raw rock and finished products have on occasion been included. The preliminary figures for 1938, which are now available, have been prepared by the Dominion Bureau of Statistics on a different basis from those immediately preceding, and have therefore not been shown.

Jan 1, 1940

By Jonathan Ludlow

This document is the final report of a study aimed at defining the relative contributions of various sources of respirable airborne dust on longwall faces. In order to define the contribution of various primary sources, continuous dust level data were recorded on five longwalls for an average of five shifts at each. By analysis of these data with records of face activity, it was possible to determine the overall contribution of each of the major elements of the longwall system to overall respirable dust exposure at various face locations. Average levels were determined for roof support generated dust, conveyor and intake dust and for dust levels during various shearer activities. When average levels are compared between mines, a significant degree of consistency is noted. The next phase of the study was aimed at differentiating the various dust sources associated with the shearer. To this end 'fly cuts' varying from 6 in. to 30 in. were closely monitored as were dust levels at operators' positions over the various segments of longwall cycle. These data indicated that the clearance ring of the shearer drum as a disproportionately heavy contributor to shearer dust make. A statistical analysis of the effect of shearer haulage speed on dust make revealed that high haulage speeds are associated with low specific dust make.

Jan 1, 1983

By D. S. van Vuuren

Over the last 60 years many different processes were conceived to reduce the cost of titanium produced by the Kroll process. However, success eluded all previous efforts, which were consequently terminated in periods of economic downturn. Recently, the grow thin demand for titanium and the high cost of producing the metal again sparked renewed attempts in various parts of the world to replace the antiquated Kroll process with a more efficient route. The different options to produce titanium are reviewed, classified and evaluated in terms of the fundamentals underlying the technologies, and it is shown that the options considered to be the most likely to replace the Kroll process, are continuous processes to reduce TiCl4 metallo-thermically to titanium powder. Of these, continuous magnesio-thermic reduction of TiCl4 would conceptually result in the lowest-cost and highest-value product. However, when considering by-product salt removal from the titanium product and recycling of the salt as well, sodio-thermic reduction of TiCl4 is better.

Jan 1, 2009

By Circadian Technologies

Alertness levels naturally fluctuate during the day and night Basic functions ??digestion, body temperature ? follow predictable 24-hour patterns Adjustment to night work creates health challenges for shiftworkers Performance decreases during overnight and post-lunch dip hours Fatigue supercedes training & experience Fatigue is a major cause of human error

Jan 1, 2010

By M Graham, R Brunning, C Andringa-Bate, S Westergren

In 2010, Rio Tinto Iron Ore’s operations commenced the planning and design of a sampling and analysis system for the new 50 Mt/a Cape Lambert Port B (CLB) facility. Current sampling systems at the ports consist of automated robotic, mass-based sampling protocols employed at Dampier, and semi-automated, time-based sampling systems operating at Cape Lambert Port A.The new sampling system at CLB has brought together a fully automated sampling and analysis system utilising time-based sampling, with the capacity to sample ore products of medium quality variation as defined in ISO 3082 (ISO, 2009). The CLB system is required to sample at shiploading rates from 6000 t/h to 13 440 t/h and provide full load-port analysis. The sampling approach is to proportionally extend primary increments (of varying mass relative to shiploading rate) to a standard length using variable speed aero-belt conveyor systems. This enables a fixed number of secondary cuts to be achieved for all primary increment masses and to be delivered to the automated cell. The cell is required to be capable of concurrently processing four individual shipments, each containing multiple cargoes.Achieving the target sampling precision for all export cargo sizes has culminated in the planning, design and construction of the largest automated iron ore port laboratory in the world. The CLB sampling and analysis cell was commissioned in Q3 and Q4 2013. This paper discusses the sampling philosophy and commissioning outcomes.CITATION:Brunning, R, Andringa-Bate, C, Graham, M and Westergren, S, 2014. Cape Lambert Port B shiploading, sampling and analysis, in Proceedings Sampling 2014 , pp 79–90 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By N. I. Jayaraman

High-pressure shrouded sprays were first tested on a bench to determine air-moving capability and dust collection efficiency. The bench-scale tests indicated that at 500 psi and above, the dust collection efficiency, when sampled downstream of a water eliminator, was about 99 pet for two types of nozzles. However, for the same water flow, the induced airflow was about three times greater in one type than in another. Since the only difference in the nozzles was the spray angle, this factor was important in air movement through a shrouded spray. Full-scale model mine tests were then conducted to determine the reduction in dust concentration behind the line curtain and at the operator position produced by high-pressure sprays in a shroud. The shroud was mounted on top of the boom of a model continuous miner, and high-pressure (greater than 500 psi) sprays were installed inside the shroud. The inlet of dusty air to the shroud was open toward the face and the outlet toward the exhaust line curtain. The high-pressure sprays were compared with conventional sprays mounted at the head of the continuous miner and directing water toward the face. The difference at the operator position (opposite side of brattice) was significant in that, under certain conditions, with conventional sprays an increase in respirable dust concentration of 471 pet was noticed compared with dry operation due to rollback from face. High-pressure shrouded sprays, on the other hand, decreased the dust concentrations at the operator position (opposite side of brattice) by 28.2 pct.

Jan 1, 1981