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By W. H. Holtzhausen

The purpose of this project was to compare two underground, batch coal haulers ? battery haulers and shuttle cars ? in order to determine the more viable machine to implement. The specific standards for battery haulers were investigated and compared to the requirements of shuttle cars in order to identify the unnecessary expenses related to the legal requirements that are attached to the machines. Costs such as running costs, capital costs, and maintenance costs were researched and compared over a typical life of machine. Average production rates and breakdown times were obtained and used to determine which machine would be more reliable in achieving the required annual production.

Jan 1, 2014

By Michael Rieber

A new mode of coal transportation based on the principles of pneumatic conveying has been recently, proposed by Soo, et al. [5]. Pneumatic transport is not a novel concept and commercial experience with pneumatic pipelines for short haul distances is plentiful. The list of applications is long and includes transporting ores, chemicals and pharmaceutical products, agricultural products, and domestic and industrial wastes. The study by Soo, et al. [5] updated an earlier one [l0] and presented the most recent economic evaluation of pneumatic transportation of coal. Their preliminary study concluded that there are immediate advantages for short-distance transport (less than 100 miles) and that it is both technologically and economically feasible. That study also concludes that pneumatic transport has a higher potential and more promising profitability in long-distance applications than rail if new track and roadbed must be built. Some of the advantages of long and short distance pneumatic pipeline transport of coal compared to rail and slurry transport are: 1) Replacement of diesel fuel consumed by unit trains, as the pipeline can be powered by coal-generated electricity; 2) Reduction of the skilled-labor costs required for upgrading and maintaining railroads; 3) Elimination of signaling, rerouting and overpass costs due to increased rail traffic on' mainline trackage;

Jan 1, 1977

By S. S. Sephton

The La Perla Mine, owned by Altos Hornos de Mexico, S.A., is located approximately 100 miles east of the City of Chihuahua in the State of Chihuahua, Mexico. The mine began operations in 1958. Existing ore beneficiating facilities, consisting of heavy media and jig plants, upgrade the ore prior to shipment by rail to the Altos Hornos steelmaking complex in Monclova. Sizable reserves of two distinct ore types, which were not amenable to treatment in the existing beneficiating plant, or usable in the blast furnaces, have been mined and stockpiled in order to uncover the treatable ores. One of these ore types has been labeled "Diseminado" ore, and is low grade containing approximately 42% Fe with sulphurs ranging from 1 to 2%. The other ore type has been labeled "Pulverulento" ore, and is high grade containing approximately 65% Fe and 0.1% S, but at 80% minus 325 mesh, is too fine grained for efficient sintering. Late in 1968, Arthur G. McKee & Company became involved with the problem of improving the above ores for their efficient and economical use in Altos Hornos' blast furnaces. Early in 1969 representative samples of Diseminado ore were obtained for laboratory bench-scale testing at the University of Minnesota, Mineral Resources Research Center. Concentration tests incorporating magnetic roasting, wet magnetic separation, high intensity separation, high tension magnetic separation, anionic flotation of apatite, cationic flotation of silica and oleic acid flotation of iron were performed. Laboratory testing was concurrently carried on at La Perla Laboratory, which resulted in plans to construct a 10 TPD pilot plant. The pilot plant was operational in September, 1969. Analyzing laboratory results as well as pilot plant results, Altos Hornos and Arthur G. McKee & Company metallurgists agreed that the most promising flowsheet for the low grade Diseminado ores entailed wet magnetic cobbing, desliming, and oleic acid flotation of the non-magnetic fraction. A combined concentrate of

Jan 1, 1972

By Carl L. Bieniewski

In a Bureau of Mines supply evaluation, the known uranium resources in the United States are estimated to have a total recoverable uranium oxide (U3O8) content of 3,132,400 tons at prices up to $69.32 per pound. Only those resources were evaluated for which sufficient quantity data are available and process technology exists for recovering uranium. A total of 160,800 tons of U3O8 is available at $8 per pound from ore deposits presently mined and an additional 244,700 tons available at prices up to $30 per pound from similar but usually lower grade deposits. A total of 2,726,900 tons of U3O8 is available from four other resources: copper leach solutions, wet-process phosphoric acid, Florida phosphate rock Leached zone, and Chattanooga Shale. These resources contain from 30,000 tons of recoverable U30, at a price of $7.52 per pound as a byproduct of copper leach solutions to 2,557,300 tons at a price of $69.32 per pound from Chattanooga Shale.

Jan 1, 1971

By B. P. Bellport

This paper summarizes the Bureau of Reclamation's experience in the use of boring machines to excavate six major tunnels on the Bureau's water resources development projects in the western United States. The summary of experience is presented as a compilation of brief case studies for each of the six tunnels. Each compilation presents data on the tunnel dimensions, geological characteristics of the excavated rock, the tunneling machine used, machine operation, muck handling, method of tunnel support, ventilation system, and related information. The listing of the six tunnels in Table 1 reflects a diversity of tunnel lengths and diameters. However, despite this diversity of dimensions as well as the variety of rock encountered during excavation, the six tunnels have one major characteristic in common: their excavation was significantly expedited by the use of boring machines. Beginning with the 10,079-foot-long Tunnel No. 1 on the Navajo Indian Irrigation Project in New Mexico - the Bureau's first tunnel to be excavated by a boring machine - the boring machines, or "moles," have demonstrated their effectiveness in rapid and economical tunnel excavation. Tunnel No. 1, virtually 2 miles long, was bored through in 9 months, an unprecedented achievement in Bureau engineering experience, as compared with tunnels previously excavated by conventional means. Boring of the 45,630-foot-long Blanco Tunnel and the 26,610-foot-long Oso Tunnel, both on the San Juan-Chama Project in Colorado, set world records in rates of excavation,l/* Two days of exceptional progress highlighted the

Jan 1, 1970

By David Roncalla, Emma Flores, Juan Pérez

Se ha co creado a Rurana, Centro de Innovación Social de Asociación Pataz, para coadyuvar en el abordaje de los desafíos de triple impacto, basados en la innovación como un evento sistémico con direccionalidad de largo plazo, pero con pasos de corto y mediano plazo para desarrollar las capacidades requeridas para el logro de Misiones, propósitos de gran impacto enmarcados en la teoría de Mariana Mazzucato.

Sep 29, 2023

By John Quiñones de la Cruz

Para tener éxito en el planeamiento de minado, es necesario establecer los requerimientos técnicos y metodólogicos para la automatización, la recolección, manejo y el análisis de datos geológicos e ingeniería. En ese sentido, el presente trabajo señala el uso de un sistema computarizado de modelamiento geológico y planificado tridimensional como herramienta para la planificación eficaz del proceso de minado. La secuencia de minado con 5D Planner, permite planificar la mina para operaciones de explotación subterránea. así como mejorar el planeamiento en etapas previas a la estimación del Valor Actual Neto Económico (VANE) del proyecto.

Apr 1, 2016

By J. P. Dick

THIS paper is a description of the milling practice and metallurgy at the Moneta Porcupine mine, Timmins, Ontario. The results obtained with an all-cyanide circuit and later with flotation followed by cyanidation are described. The ?investigation which prompted the various changes in milling practice have also been dealt with. Moneta ore is possibly the most refractory now being milled in the Porcupine district. This is due to the ultra fine state in which the gold occurs and to its intimate association with pyrite. No doubt there is ore of similar characteristics on the neighbouring properties but it probably forms only a small portion of the tonnage being mined, whereas at Moneta the bulk of the ore requires an extremely fine grind to liberate the gold. The fineness to which an ore can be ground economically has gone far beyond what was thought to be the limit only a few years ago. Formerly, a set of standard screens was all that was required to measure the fineness to which an ore was ground. At present, the Haultain infrasizer is practically indispensable, and the nominal micron has become a familiar unit of measurement to all those dealing with the problems of fine grinding.

Jan 1, 1941

The Hopi Reservation is in Arizona, where coal mining can be traced to the 13th century. Bituminous coal is found in varying quantities throughout the Hopi Reservation. The Hopi Tribe has a 50 percent mineral interest in the coal resources of the joint-use area adjacent to the Navajo reservation. The only coal presently mined on acornrnercial scale from lands in which the Hopi Tribe has an interest is from the Wepo formation at the Black Mesa and Kayenta Mines. These two large surface mines, located over 50 miles northeast of most Hopi settlements, have disturbed more than 6,000 acres. Income from royalties generated by the mines provides significant economic support for the Hopi Tribe. The Office of Surface Mining's Albuquerque, New Mexico, Field Office is responsible for regulating mining and reclamation on Hopi land. The Hopi Abandoned Mine Land Program was approved June 28,1988.

Jan 1, 1992

By Anthony T. Eyton

Intelligent Systems: Advantages for Mining ? Increased safety (reduced risk to workers) ? Increased productivity (reduced downtime) ? Reduced maintenance costs ? Customized solutions for different mines ? Growing acceptance among mine managers A Typical Precarn Project ? Meets definition of intelligent systems ? Involves at least two Precarn members ? a technology developer partner and a user partner ? in a true collaboration ? Involves at least one university and may have various other players ? Leads to a demonstrated prototype ? Costs $2-4 million, and lasts 12-30 months ? Gets up to 40% of its funding from Precarn (max. $1 m) ? Produces new intellectual property -- owned by the project team

May 1, 2002

By Charles R. Keyes

A COMPLETE transformation has taken place in the boras industry during the year 1908. A most remarkable factor in this radical change in method of producing the crude borates has been its removal from the realm of industrial chemistry to the field of mining. With the development of extensive deposits of borate-minerals interstratified in thick sequences of Tertiary clays and sands, their winning becomes a strictly mining-enterprise, of the same kind and of the same certainty as the digging of coal or iron-ore. The major supply of the world's production of commercial borax now comes from the United States. While formerly all of the boric salts of commerce were laboriously extracted from the waters of saline lakes of the arid regions, or from the bottom-salts of desiccated ponds, it later was largely slowly leached from ancient desert shales and clays. During these periods the borax industry was a very hazardous and expensive vocation.

Oct 1, 1909

By B. J. Moore

This publication contains routine analyses and related source data for 547 natural gas samples from 22 States and three foreign countries. Of this total, 340 samples were collected during calendar year 1967. The remaining 207 analyses are of samples collected during previous years, but releases granting, permission to publish the results were not received until 1967. All samples were collected as a part of a continuous survey of the free world for occurrences of helium in natural gas. The Bureau of Mines has conducted this survey in the United States since 1917, and in 1965 it was expanded to include foreign gasfields. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus which are described in Bureau of Mines Bulletins 4863 and 516.4 Nine previous publications have been made to present results of 7,618 gas analyses made by the Bureau of Mines Helium Activity prior to 1967. The first three, Bulletins 486,5 576,6 and 6177 contain analyses and related source data on 5,218 gas samples collected from 1917 through 1960. The other six

Jan 1, 1968

By T. C. King

AT the new Graham-Central Mill of Eagle-Picher, near Galena, Ill., material is simultaneously dewatered and introduced into the ball-mill scoop boxes by the use of variable-speed, 24-in. spiral classifiers. This arrangement has proved satisfactory in that the moisture content of the wet feed is reduced, thus allowing maintenance of density within the mills, and a constant feed at any desired rate to the mills is provided. In this mill the primary feed is wet crushed to minus 1/2 in. and preconcentrated by jigs to produce a bulk lead-zinc-iron concentrate and a waste tailing. The jig concentrate is then dewatered by a conventional dewatering classifier and stored in bins ahead of the ball mills. Even though this material is well dewatered, the discharge at the bin bottom is sloppy because of the gradual drainage of the water from the surface of the particles. Conventional belt feeders with vertical cutoff gates are unsatisfactory because of the flushing characteristic of the wet sand. The new installation employs 24 in. x 10 ft, 9-in. Simplex double-pitch spiral classifiers for feeders from the bin bottoms to the ball mill scoop boxes (fig. 1). These units are arranged with straight tanks and are driven by 5 hp motors through a U. S. Vari-Drive to provide a 4 to 1 speed ratio. Each bin discharges through a chute into the rising side of the spiral. The flushing characteristic of the material from the bottom of the bin is utilized to maintain a steady feed. A small amount of water tapped into the bottom of the bin insures uniform feed to the classifier. Excess clear water drains over the weirs. Feed rate to the mills is controlled by the variable-speed drives. The feed delivered by the spiral at a given speed setting is relatively dry, uniform, and steady, and as such is easily controlled by the operator. The classifiers are set on a pitch of 5 in. per ft and have a sand-raking capacity of from 8 to 32 tons per hr. It is believed that the solution of this problem offers possibilities for the storage of deslimed rod-mill sands and other similar products of the industry.

Jan 1, 1951

By T. C. King

AT the new Graham-Central Mill of Eagle-Picher, near Galena, Ill., material is simultaneously dewatered and introduced into the ball-mill scoop boxes by the use of variable-speed, 24-in. spiral classifiers. This arrangement has proved satisfactory in that the moisture content of the wet feed is reduced, thus allowing maintenance of density within the mills, and a constant feed at any desired rate to the mills is provided. In this mill the primary feed is wet crushed to minus 1/2 in. and preconcentrated by jigs to produce a bulk lead-zinc-iron concentrate and a waste tailing. The jig concentrate is then dewatered by a conventional dewatering classifier and stored in bins ahead of the ball mills. Even though this material is well dewatered, the discharge at the bin bottom is sloppy because of the gradual drainage of the water from the surface of the particles. Conventional belt feeders with vertical cutoff gates are unsatisfactory because of the flushing characteristic of the wet sand. The new installation employs 24 in. x 10 ft, 9-in. Simplex double-pitch spiral classifiers for feeders from the bin bottoms to the ball mill scoop boxes (fig. 1). These units are arranged with straight tanks and are driven by 5 hp motors through a U. S. Vari-Drive to provide a 4 to 1 speed ratio. Each bin discharges through a chute into the rising side of the spiral. The flushing characteristic of the material from the bottom of the bin is utilized to maintain a steady feed. A small amount of water tapped into the bottom of the bin insures uniform feed to the classifier. Excess clear water drains over the weirs. Feed rate to the mills is controlled by the variable-speed drives. The feed delivered by the spiral at a given speed setting is relatively dry, uniform, and steady, and as such is easily controlled by the operator. The classifiers are set on a pitch of 5 in. per ft and have a sand-raking capacity of from 8 to 32 tons per hr. It is believed that the solution of this problem offers possibilities for the storage of deslimed rod-mill sands and other similar products of the industry.

Jan 1, 1951

By Aurel Goodwin

Remarks of Aurel Goodwin, Chief, Division of Health, Metal and Nonmetal Mine Safety and Health, Mine Safety and fEealth Administration, U. S. Department of Labor, before the Society of Mining Engineers of the AIME, Littleton, Colorado, on October 18, 1979. I appreciate this opportunity to speak before the Society of Mining Engineers of the AIME. The topic of my presentation is the Mine Safety and Health Administrations's (MSHA) concern and obligations with regard to asbestiform minerals. Asbestiform minerals - the magical group of hydrated, silicate minerals which possess a fiber like structure capable of being woven, like and into cloth. Their unique combination of properties, such as resistance to heat and chemical attack, high tensile strength, and flexibility was recognized centuries before Christ. Pausanias, the early Greek geographer, speaks of golden lamps made about 430 B.C. with incombustible wicks of "Carpathian flax." The Romans used asbestos as cremation clothes to conserve the ashes of deceased persons of rank. Charlemagne had an asbestos table cloth that he used to pass through fire to clean (1). Early recognition of the health hazards associated with exposure to asbestos was documented in the first century by Pliny the Elder, a Roman naturalist, and Strabo, a Greek geographer. Bath wrote of slaves with sickness of the lungs, whose occupation was that of weaving asbestos into cloth. This concern for the health of asbestos workers disappeared over the ages.

Jan 1, 1979

"A bed, British Columbia, Canada, coal, carbonizingproperties B 510Pa., coal, washing characteristics RI 4941A' bed, Pa., coal, washing characteristics RI 4834"

Jan 1, 1960

By Ogden Tweto

The classes of ore deposits in the mountain province of Colorado that have been the most productive in the past and that offer the greatest promise for the future are: (1) disseminated or stockwork molybdenum deposits associated with Tertiary stocks; (2) combination precious- and base-metal veins in Tertiary volcanic rocks; and (3) base-metal replacement deposits and veins in Paleozoic sedimentary rocks. Veins in Precambrian rocks, including precious metal-bearing sulfide veins, gold-silver telluride veins, and tungsten veins, have been mined extensively in the past, but their aggregate output has been far subordinate to that of the groups named above, and the outlook for major output from them in the future is poor. Principal ore deposits of south-central Wyoming are sedimentary iron ores of Precambrian age and uranium deposits in Tertiary sedimentary rocks. Precambrian deposits of several kinds are scattered through the mountains of both states. The most promising of these, based on present indications, are vanadiferous titaniferous magnetite in southern Wyoming and southwestern Colorado and thorium-niobium rare-earth deposits associated with alkalic intrusive complexes in Colorado. Most of the mining districts of Colorado are in the Colorado mineral belt, a generally narrow but somewhat irregular belt that extends northeastward across the north-trending mountain ranges and the north-northwest trending geologic grain of the state. The belt is characterized by intrusive rocks of Laramide and younger age and by ore deposits, and it occupies environments ranging from Precambrian crystalline rocks through Paleozoic and Mesozoic sedimentary rocks to Tertiary volcanic rocks. Two ages of intrusion and ore deposition recently have been recognized in the mineral belt. One is Laramide (late Cretaceous and early Tertiary), and the other is Oligocene. As interpreted herein, the major replacement deposits and most of the sulfide vein deposits in Precambrian and sedimentary rocks are Laramide in age, and the molybdenum deposits, the tungsten and the gold telluride veins in Precambrian rocks, and the precious- and base-metal veins in volcanic rocks are Oligocene in age. In general, the Laramide deposits are mesothermal in aspect, and the Oligocene deposits are principally epithermal. The existence of two mineralization stages, in considerable part characterized by different suites of metals, has many applications in exploration.

Jan 1, 1968

A prototype EM Location System was fabricated and tested at the Geneva Mine near Dragerton, Utah. This system consisted of six manpack transmitters and six manpack receivers covering the frequency band from 900 Hz to 2900 Hz as well as a six channel receiver designed for use, in a helicopter. Tests showed that EM signals from lightweight (3/4 lb) transmitters could be detected both on the surface and from a helicopter through as much as 4450 ft of relatively high conductivity (2 X 10- 2 mhos/m) overburden. Furthermore, the resulting field strength profiles could be used to determine source location to within 150 ft of the actual surveyed location in the mine. Modifications were made to a Monitoring, Locating and Communications System being tested at the Bruceton Mine, Pittsburgh, Pennsylvania. These modifications have improved the performance and quality of the paging and voice telephony mode of the system. Subsurface receiver modifications have improved reception of voice downlink signals.

Jan 1, 1973

By AIME AIME

THE following paragraphs comprise such information as the Secretary has been able to obtain concerning the members and associates whose deaths have been reported. Further particulars or corrections of errors, and biographical data concerning deceased members or associates not already noticed in this way, are solicited. [SECRETARY'S NOTE.-All of these notices have been revised, and some of then have been more or less completely prepared, by me. To those which contain more particularly the expression of my personal feeling, my initials have been appended. The labor of preparing or editing these paragraphs has been in many respects both welcome and interesting, on the one hand, and sorrowful, on the other. In going through the list, I have repeatedly felt like one who, visiting the Morgue, suddenly comes upon the pale face of a dear friend, of whose death lie was not aware ; and, even when this fact was known to me, the work of recording it has brought upon me a flood of recollections, almost preventing the discharge of that official duty. The list for 1907 seems to me to he peculiarly sad, comprising, as it does, so many sudden deaths by violence or accident, so many veterans, removed too soon, and so many young men whose early departure impoverishes the future, even more than the present. Probably, this feeling on my part is largely due to the circumstance that the increased membership of the Institute necessarily in¬volves an increase of the annual death-list. Probably, also, it is connected with the circumstance that during the first years of the history of the Institute-say from 1871 to 1880-it was joined by men of all ages, and that the death-rate is consequently now above the average which would result from the normal annual addition, principally of young men. And finally, I must admit that, as one of the original members of the Institute, and practically connected with it for nearly thirty-seven years as Acting President, President or Secretary, I am peculiarly impressed and depressed by the successive deaths of those who were my associates in the years of its early struggles and triumphs. I do not wish to inflict upon my younger colleagues the melancholy reflections of an increasingly lonesome old man. In fact, my prevailing mood concerning the Institute is not at all melancholy, but triumphant and hopeful. If I may be permitted to preach at all, I would enforce, from the texts given below, a moral which many of them declare so forcibly as to preclude the necessity of expository enforcements-namely, the duty of every one of us, old or young, to give to his brethren, as he goes along, and without waiting for some future occasion for a comprehensive and monumental contribution to technical literature, the results of his observation and experience. When I look at this list of names, my personal sorrow over many of them is drowned in my professional reflection as to each and all-How much has died with

Jan 1, 1908

By M. A. Barclay, D. Samson, A. M. Esteves

Several companies have adopted policies and standards aimed explicitly at increasing ‘local procurement’, recognising that local economic participation has benefits for companies and communities alike. From a corporate perspective, local economic participation is seen as one means of maintaining a social license to operate, as well as ensuring reliability of supply by having a supplier located nearby. From a community perspective, the participation of local businesses in the resource project is a means by which the benefits of resource development can flow into their communities. This paper is based on the research undertaken to produce a good practice guide for the mining, oil and gas sector. Our research revealed that the extent to which the local community will actually benefit from local procurement initiatives is dependent on the capacity of the community to supply goods and services to the project and, even more importantly, on its ability to adapt to the inevitable changes that accompany large-scale resource development. We provide guidance on adapting impact assessment tools to guide planning of procurement interventions.

Jan 1, 2011