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By Frank A. Stephens

The process of converting iron ore (principally Fe,03 or Fe30,) into iron carbide (Fe,C) to be used as feedstock for steel-making yields complex mixtures of several Fe-containing compounds as a function of processing conditions. In addition to the above compounds (hematite, magnetite and cementite), the mixtures typically contain wustite (FeO) and metallic iron(Fe). Mossbauer spectroscopy has been developed into aquantitative analytical method for monitoring the degree of conversion to carbide from samples periodically extracted from a fluidized bed reactor type of pilot plant. Calibration of absolute quantities of the above five compounds is based on standards prepared from known mixtures of the high purity individual phases. The PC-based spectrometer allows fitting of the well-known spectral components of each of the five phases, the resulting spectral areas then being compared with the calibration curves via PC software to yield the weight fraction of each. Emphasis has been placed on standardizing and simplifying the analysis procedure for routine use in an industrial environment.

Jan 1, 1993

By F. H. Daniels

IN this, paper it is my intention to, call your attention to* a few of the many producers using blast, now, in common use in Sweden, and also those constructed by the Washburn & Moen Manufacturing Company at their Quinsigamond Works. During a prolonged stay in Sweden the writer had an opportunity

Jan 1, 1881

By P. F. MINISTER

AT Lime Spur, Mont., the East Butte Copper Mining Co. has been quarrying limestone for twenty years. The quarry is beside the Northern Pacific R. R. in the Jefferson River canyon, 4 ½ miles east of Cardwell, at Lime Spur, Montana. HISTORY This quarry was opened early in 1900 by Dan Morrison of Whitehall, the discoverer of the Morrison cave, to supply a demand for smelter flux. Limestone was sold to the Pittsmont smelter of The East Butte Copper Mining Co. and to the Butte Reduction Works. As no particular effort was made at the quarry to select the rock that delivered to the smelters was unduly high in magnesia and impurities. The East Butte com¬pany, therefore. Bought the quarry. in 1909 and confined operations to the high-grade beds in order to supply rock of the desired purity for its own smelter and the Butte Reduction Works until the latter shut down. It also developed a market for some of its rock with the sugar factories. The latter market increased until in later years all rock, larger than 4 in. in size over a bar grizzly, was being shipped to the sugar factories, and the rock smaller than 4 in. was being used as a flux in the blast furnaces at the Pittsmont smelter. In 1924, the East Butte concluded a contract with the Anaconda company for the treatment of its ores, and the Pittsmont -smelter -was shut down: which made the minus 4-in. rock a useless by-product. Since there was not enough revenue in the sugar rock alone and also because of limited waste room it became necessary, if Lime Spur was to continue to operate, to increase- the proportion of plus 4-in. rock and to develop a market for the minus 4-in.

Jan 1, 1930

By Jr. Fish

As a part of a study of iron are resources in the Appalachians, 9 diamond drill holes aggregating 1,580.7 feet were drilled in a portion of the Butt Mountain area of northeastern Giles County, Virginia. Three hematitic sand-stone beds were intersected in the Clinton formation but only one was consistent in thickness and grade in all 9 drill holes. This bed averages 18.9 percent iron over an average thickness of 24 feet. The drill cores were logged and chemical analyses were made on 161 individual samples and 22 composite samples. Beneficiation studies were made of three composite hematitic sandstone samples each representing a separate bed containing 14.6, 19.8 and 20.0 per-cent iron. Major mineral constituents of the samples were hematite, quartz, and sericite.

Jan 1, 1967

By Walter Harvey Weed

Introductory.............449 Summary oF Types............452 I. The Virgilina Type...........452 The Virgilina mines...........452 Location.............452 History.............453 The rocks of the district..........453 The veins.............454 Notes on the mines.... 458 The Holloway. 458; Yancey and Durgy. 465 ; Copper World. 467 ; Frazier. 467 ; Thomas. 467 ; Anaconda. 468; Blue Wing. 468; High Hill. 472; Dorothy.......474 II. The Gold Hill Type...........474 The Gold Hill mine...........475 Location.............475 History............• 475 Surface improvements.......... 476 The rocks............478 Vein.phenomena...........478 Character of the ore..........481 Origin of the ore...........481 Notes on the mine.workings.........482 Other occurrences of ore-deposits of the Gold Hill type.. .. 483 III. The Ducktown Type..........484 The Ducktown mines...........485 Other examples of the Ducktown type....... 494 Alabama mines...........494 North Carolina examples : Ore Knob.......496 Virginia examples..........497 IV. The Catoctin Type.. ......... 498 General characteristics,......... 498 The Linden district...........499 General distribution of the Catoctin type.......503 Introductory. In the early history of this country the existence of copper in the Appalachian region was well known. but no mining mas attempted until the discovery of the Ducktown deposits in

Jan 1, 1901

By Roy S. Nutter

An expert system advisor consultant to assist a coal mine section foreman is described in this report. The system is designed for an underground continuous miner section that is being specifically used for longwall development. The system provides three methods of operation that include normal operational mode for use underground, a training mode for use in training section foremen under controlled classroom conditions, and a demonstration mode that is free running. The Face Decision Support System or FDSS, is designed to interface with section environmental monitoring equipment and section production monitoring equipment that may appear in the future. This provides automated reprioritzation of the section foreman's job list from the system. The system 1S written in LASER which is written in C and is operated under the UNIX operating system. The objective of the entire FOSS system is to ensure that no job or piece of information important to safety or to production is forgotten because of the immediate problems confronting the section foreman.

Jan 1, 1988

By Robert S. Warfield

The Federal Bureau of mines and U.S. Geological Survey conducted exploratory investigations and geologic mapping in the Wishbone Hill district of the Matanuska coalfield almost continuously from 1942 through 1958. These investigations delineated reserves of high-volatile bituminous coal necessary to supply the rapidly expanding military and civilian requirements in the Anchorage area. This report describes the program conducted by the Bureau of Mines from 1949 through 1958, and briefly summarizes previous investigations, the results of which have already been published. The coal-bearing structure on both the north and south limbs of the prominent Wishbone Hill syncline was explored by 8,719 feet of churn drilling and 25,460 feet of diamond-core drilling. A total of 33 holes were drilled ranging in depth from 60 to 2,114 feet. To supplement the drilling operations, bulldozer and dragline trenching were undertaken at key locations; about 25,000 cubic yards of dragline trench were excavated in the vicinity of the old Premier mine.

Jan 1, 1962

By Adabala Raja Venkata Sai Naresh, Radhakanta Koner

Particle size distribution (PSD) is an essential parameter in assessing the overall efficiency of blasting operations in mines and the subsequent mine-to-mill process in the mining industry. Despite some drawbacks of 2D image analysis techniques in accurately estimating particle sizes in PSD, the mining industry has relied on them for the last three decades. This study proposes the 3D rock fragmentation measurement (3DFM) technique for deducting the accurate dimensions of 3D rock particles for the PSD. 3DFM has utilized different processing algorithms. Images of different views of the non-touching rock particles of varying sizes have been acquired as a data acquisition step of structure from motion technology for generating sparse point cloud. Dense point cloud reconstruction is used to avail finer details of the point cloud using clustering views for the multi-view stereo algorithm. Random sample consensus (RANSAC) algorithm coupled with an unsupervised classification using the density-based spatial clustering of applications with noise (DBSCAN) classifier is employed to extract the rock clusters from the 3D point cloud. Finally, the accurate rock sizes are derived using the hybrid bounding box rotation identification (HYBBRID) algorithm with a root mean square error (RMSE) of 0.10 cm for length, 0.10 cm for breadth, and 0.32 cm for depth. The PSD of rock fragments obtained from the proposed 3DFM technique is found to be matching with the results of mechanical sieving and manual gauging with an R2 values of 0.98 and 0.99, respectively. The 3DFM method can be considered cheaper, more accurate, and computationally faster in determining the rock dimensions for the PSD determination method to enhance the productivity of the mining industry.

Dec 29, 2023

By Steve Dillingham

PHYSICAL BLAST DATA Pattern Description All measurements related to the description of the physical blast pattern must be made with the mind-set that it has to tell a powerful factual story enabling a future accurate reconstruction of the event. A case has never been lost because too much factual information was available to assist investigators. An accurate physical description of the pattern must be provided based on the blaster’s observations of the pattern actually loaded. The blaster must measure the pattern size, depth, face heights, etc., recording only accurate results. All too often, a blaster records simple pattern sizes and information relayed to him or her from the driller, or from a phone call into the office the night before for powder pre-load inventory purposes. If a pattern was actually measured on the job site by the blaster to be 8.5 x 9.5’, it may, in fact, originally have been ordered at 9’x9’, 8’x9’, or 9’x l0’. In a claim situation, particularly flyrock, recording a “generalization” of what was loaded could result in an interpretation of a blaster’s negligence due to “not knowing or caring” what the actual pattern was, and not loading appropriately for conditions. It is important to remember that other documentation exists such as a drill log from a contract driller or mine records that may provide a different interpretation of the loaded pattern.

Jan 1, 2002

By R. D. Brown

Ever since British Columbia started the ball rolling in 1974 with the introduction of its now-defunct Mineral Royalties Act, all Canada's resource-based provinces have significantly altered their mining tax systems. The last resource-based province to abandon its pre -1974 mining tax structure is New Brunswick, which introduced a new mining tax regime in the summer of 1977 to take effect from April 1 1977. The new structure, which represents the outcome of considerable study and discussions with industry representatives, contains some intriguing concepts which make Nero Brunswick's new mining tax system unique among the Canadian provinces.

Jan 1, 1977

By C. Bester, G. M. Rohde

A major challenge in the mining sector is the responsible management and efficient storage of mine residue. Over recent years numerous tailings dams have experienced unintended spills and failures, with severe consequences for the mining industry, the environment, local communities, and the regional economy. The fourth industrial revolution (4IR) is impacting society due to increased interconnectivity, processing speed, and automated technologies. This paper explores whether 4IR technologies have the potential to mitigate risks associated with tailings dams. Experts in the field of tailings dam operational management were surveyed to determine their view on the risks associated with tailings dams and the potential of 4IR technologies to mitigate these risks. The survey found that a majority of experts believe that certain 4IR technologies have the potential to reduce the risks associated with tailings dam failures.

May 27, 2025

By Mackenzie Burnett

The Brattice Window Method was used to measure the leakage rates of a total of 42 ventilation stoppings in 8 hardrock mines. Various types of stopping construction were evaluated. The following types are listed in order of decreasing effectiveness: 1) Cinder block, 2) Timber and mortar, 3) Timber and polyurethane foam, and 4) Timber and brattice material. There are slight differences in the effectiveness of the first three types, while the timber and brattice type is substantially inferior to the others. The repeatability of the Brattice Window Method was found to vary with physical conditions in the mine such as stopping location with respect to intersections, regularity of drift cross section, and the presence of hardware such as air and water pipes, timber sets and wire mesh. The Brattice Window Method is viewed primarily as a tool for estimating and comparing stopping leakages for the purpose of determining where repair efforts should be concentrated. A laboratory test program resulted in the derivation of several "rules of thumb" for employing the Brattice Window Method, which will aid in securing accurate and repeatable data.

Jan 1, 1979

By Agustín Arias

El presente artículo describe brevemente la historia, métodos de explotación, mecanización, energía eléctrica, las plantas de preconcentración y flotación y el consumo de reactivos de la compañía minera Milpo.

Nov 1, 1954

DAVID THOMAS 1871 R.W. RAYMOND 1872-1874 A.L. HOLLEY 1875 ABRAM S. HEWITT 1876 T. STERRY HUNT 1877 ECKLEY B. COXE 1878-1879 WILLIAM P. SHINN 1880 RICHARD P. ROTHWELL 1881

Jan 1, 1932

By W. L. Price

The intelligent selection of wire cloth and perforated plate for screening surfaces seems a rather confusing subject to the newcomer in aggregate processing. The proper application of various screening surfaces is a complicated one and one could consider himself an expert only after many years of working with all applications. However, part of the subject matter could be simplified considerably for, the average screen user. In this paper an attempt will be made to do this, by presenting some comparative specification data along with cost figures Unfortunately, it is impossible in the limited scope of this paper to give actual service comparison records between different cloths or cloth and plate. Anyone who has considered making actual service comparisons for competing screening media is well aware of the almost insurmountable problems Their solution would form the basis for a separate paper on that subject alone. Therefore, this paper will be limited to comparative data up to the point of installation.

Jan 1, 1961

By R. D. Berkenkotter

This report describes a weighted method for evaluating the mean and variance of assay data from samples of different length . The method , which produces unbiased estimates from which valid confidence limits can be computed , is appropriate for bedded deposits of variable bed thickness and for vein deposits of variable vein width . Assay data from the bedded Florida phosphate deposit is used to illustrate the procedure .

Jan 1, 1964

By Harry Gard Knox, F. R. Harris

This paper covers some of the problems presented to the oil industry in the drilling of oil wells in the open waters of the Gulf of Mexico. The hazards, delays and relative costs of offshore drilling are reviewed and various forms of drilling platforms discussed. The requirements of the offshore drilling rig are summarized together with the principal items affecting the cost of construction. Sea waves and their size and characteristics as affecting offshore platforms are reviewed. Drilling platforms are classified as fixed, or fixed and floating. Fixed platforms of the conventional cofferdam and pile-supported type are discussed together with their good points and their limitations. The desirability is pointed out of eliminating as much offshore work as possible where operations are subjected to constant and expensive delay and substituting therefor the prefabrication of structures ashore or in sheltered waters. Marked economy will come with the standardization of offshore rigs aid special means of transporting them to the site. Several types of structure which are partly pile-supported and partly buoyancy-supported are discussed and their possibilities of future usefulness commented upon. General Considerations The predominant attribute of offshore drilling equipment is that it must be equal to the job in hand. We therefore give first thought to the matter of adequacy. In view of the probable depth of drilling, the investment involved and the per diem labor costs, it is assumed heavy modern drilling equipment will be employed. In order to usc such equipment efficiently, the working deck must be ample in size and strength and supported so as to be relatively free from motion and from green seas even in heavy storms. These requirements necessitate a high and rigid land-based support for the drilling rig and machinery with plenty of space for supplies, such as pipe, mud, water and fuel, with reserves for days when transportation from shore is impracticable. In offshore rigs the crew will be housed onboard in comfortable quarters, probably air conditioned and equipped with a galley and refrigerated food storage. An important consideration will be the ability to transfer stores and crew to and from the rig in all but the heaviest weather and the platforms must be protected from the impact of supply vessels when alongside. It will be essential to maintain continuous communication with shore by radio or cable, not forgetting the possibility of a helicopter landing space for the transfer of crew and light stores as well as a means of general communication. Whatever structure is constructed must be secure from storms of hurricane force and a safe place for the operating crew to work. If the well comes in, the drilling rig will presumably be removed and a small but rugged pile-supported platform will remain to carry the Christmas tree with safe working space around it. It will be protected from damage on all sides by buffer piles or dolphins. It is assumed that the flowing oil will be piped to storage tanks in the vicinity of the well. An individual tank for each well or a

Jan 1, 1949

By J. F. Kemp

The use of nickel-steel has directed increasing interest of late towards the deposits of nickel, and at the same time the parallel advance in our knowledge of the basic igneous rocks has rendered these deposits a subject of important geological inquiry. Investigations have led to some views, more or less new, on the igneous origin of certain ores, which, though not universally accepted, have a growing number of adherents. In Europe, the mines in Norway have been especially suggestive subjects of study, and others somewhat less generally known have also added their testimony; while in this country the great economic importance and scientific interest of the developments in the Sudbury district of Canada, have furnished the principal texts for the discourses that have appeared among us. The purpose of the present paper is to set forth these views through the medium of one interesting ore-body, of which but little has been written ; and, by the description of another, to place in contrast two different geological associations in which nickeliferous pyrrhotite occurs, and to indicate a generalization, based upon these different geological characters, and justified by the experience so far gained. To Prof. J. H. L. Vogt, of Christiania, Norway, is due the chief credit for the revival of interest in the geology of nickel. His important contributions* of recent date have made generally available

Jan 1, 1895

By Walter Díaz Cartagena

El suelo es uno de los recursos más importantes del agua -en tanto sustenta la vida natural y fuente de alimento para toda la especie terrestre. Por tal motivo, el presente texto señala los planes y estrategias para el cumplimiento de los estándares de calidad (EKA) de los suelos. En la promulgación de D.S. N°02 2013-MINAM que aprueba dichos estándares, se establece el último componente por norma para conocer la cantidad de contaminación del suelo. Este decreto propone una serie de etapas en la gestión de suelos contaminados que van desde la ecuación de los instrumentos de gestión ambiental, la investigación de situación de estos suelos contaminados en la zona de producción para determinar el estado en el que se encuentran y la recuperación ambiental por parte de un plan de descontaminación de suelos.

Jul 1, 2014

By F. C. Foshag, P. E. Wingrove

The Kayford, Boone and Nicholas Division of Bethlehem Mines Corp. operates a modern coal preparation plant in Van, WV. Since start-up of the Van plant in 1976 until the summer of 1980, the refuse handling system proved to be a costly maintenance problem and a material handling bottleneck. During the 1980 two-week miners' vacation, the original system - which included two screw conveyors and a drag conveyor - was replaced by an installation using two Flexowall steep angle belt conveyors. This paper describes the technical and economic analysis that led to the new installation and reviews its first year operating performance.

Jan 1, 1983