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By John R. Bartels

This report discusses an improved method for rerailing underground railcars devised in a joint effort by the Bureau of Mines and Hoesch MFD. This improved method utilizes a lightweight hydraulic ram with hand-pump activation to move a bridge-mounted roller carriage in conjunction with steel-reinforced air-lift bags. This method provides a lightweight portable system in which only two workers are required to perform the mine car rerailing operation. Because of the very narrow confines in underground mines, use of overhead cranes and other surface rail techniques is not possible. This new system is designed for very low profile work, and provides the necessary lifting force from light- weight compressed-air bottles.

Jan 1, 1985

By Daniel Andrade Paes de Lima, Gerson Evaristo de Paula Júnior, Beatriz Fausta Gandra

The gradual reduction of the sinter feed size has been a complicating factor in the maintenance of sintering productivity. In addition, pellet feeds have been used for chemical correction. Because of this, it is necessary an effective cold agglomeration step in sintering to keep the ironmaking competitiveness. Thus, in the present paper, four different technological routes for cold agglomeration with sinter feeds (drum mixer, intensive mixer + drum, double drum and HPS - Hybrid Pelletized Sinter) were evaluated in pilot scale and their impacts on the indicators of the sintering and the sinter quality was obtained. It was found that the best results on granulation index and, consequently, productivity were obtained in the route using HPS. However, the sinter from this process was the most fragile among the analyzed ones. The performance of the double drum process was superior to the intensive mixer from the point of view of productivity and sinter quality.

Oct 1, 2019

By Jorge Alberto Soares Tenório, Flávia Paulucci Cianga Silvas, Denise Crocce Romano Espinosa, Ivo André Homrich Schneider, Erika Gusmão, Daniella Cardoso Buzzi, José Roberto de Oliveira

"This study evaluated the Salvinia sp action on metals biosorption in a synthetic sample of acid mine drainage (AMD) in order to determine the time and amount of metals uptake. Biosorptives tests were realized varying the contact time of 5, 20, 60 and 240 minutes. And keeping constant the follow parameters: pH (2.6), biomass concentration (1g.L-1), temperature (25°C) and agitation (175rpm). In order to quantify the metals concentration captured by biomass, the AMD samples will be analyzed by ICP. Biosorbent, Salvinia sp., will be characterized before and after the biosorptives tests through analysis of SEM and IR. The micrographs indicate the occurrence of micro-precipitation and changes in biomass physical structure. The infrared spectra indicate changes in functional groups present in the biomass before and after the biosorptives tests.IntroductionThe current emphasis on environmental sustainability leads the industry in general, to treat their waste. The human activities are increasing, highlighting the industrial and mining activities, and have promoted the contamination of soil, waterways and groundwater by metals (1). The waste must undergo treatment processes aimed at reducing pollution, and therefore, less aggression ecosystems.This means the importance of studies of economic and effective methods to eliminate these metals from wastewater generated. The bioindicators are good investments in this area. The aquatic weeds are plants that inhabit swamps up from truly aquatic environments. They have several morphological and physiological adaptations that enable them to colonize the various aquatic environments. They are used as bioindicators of water quality and have also been used in decontamination of aquatic environments, production of biomass for livestock feed, fertilizers, soil and fish tanks (2)."

Jan 1, 2012

By D. Antonov

The physical and mechanical properties of coal play a important role in the planing and design of coal mines. However, due to the complexity conditions in situ and the influence of unknown factors, it is hard for people to evaluate the physical and mechanical properties of coal directly. In this research, uniaxial compressive stress was used to change the attribute of coal samples, and the ultrasonic measure technique was used to evaluate the physical and mechanical properties of coal. The results of laboratory test showed that there was a strong relation between uniaxial stress and velocity of ultrasonic wave. Sensitivity analysis with numerical simulation was used to define the relation between the physical-mechanical parameters of coal and ultrasonoc wave. With the dynamic analysis module of FLAC, three elastic and plastic models were built to model the coal samples. The modeling parameters were changed pro rata, and the correlation of coal and ultrasonic wave properties were summarized and presented. The result from this research will be base for further analysis of caving behavior of coal.

Jan 1, 2010

By George H. Holmes

Beryllium deposits in the northern Virgin Mountains , Clark County , Nev . , and Mohave County , Ariz . , about 70 miles northeast of Las Vegas , were investigated by the Bureau of Mines . The investigation indicated a widespread occurrence of beryllium- bearing pegmatites within an extensive belt of mica - schist . Several deposits with significant beryllium mineral concentrations were encountered . Only a few of the samples analyzed contained more than 1 percent beryllium oxide ( BeO ) ; in many of the samples , no beryllium was reported . The average tenor of samples from the more important occurrences was 0.25 percent BeO . Chrysoberyl is the predominant beryllium mineral in the pegmatite sills ; beryl predominates in the more massive bodies . Minute quantities of cesium and lithium minerals also occur , but no columbium , tantalum , or other rare minerals were found . Ore dressing tests on a composite sample containing 0.28 percent BeO which was representative of the pegmatite sills , indicated an 85 percent recovery of the chrysoberyl ( 70 percent recovery of total BeO ) by gravity concentration in a concentrate containing 17.6 percent BeO .

Jan 1, 1964

By Jr. Koch

In the Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) phase of its National Uranium Resource Evaluation (NURE) pro¬gram, the U.S. Department of Energy (DOE) samples about 1400 sites for stream sediments in each two-degree quadrangle of the National Topographic Nap Series (NTMS) and about 1200 sites for ground or stream water. Through a geological/statistical analysis, we find that NURE data are useful for assessing the uranium resources of the NTMS quadrangles. Our computer-implemented System for Uranium Resource Evaluation (SURE) calculates a score for each NTMS quadrangle based on the HSSR, geologic, and radiometric data; we score the four Colorado quadrangles--Pueblo, Montrose, Durango, and Trinidad--that comprise the study area. We interpret the scores in terms of geology and the known occurrences, which include the Hanson ore deposit with reserves of 30,000,000 lbs. U308 and the Pitch mine with reserves of 1,740,000 lbs. SURE depends in part on distinguishing mineralized or metalliferous granitoids from barren ones through "geochemical signatures."

Jan 1, 1980

The panic bars (and associated linkages and electrical circuitry) that are defined in this document are a machine operator-actuated control for the emergency deenergization of the tram motors on self-propelled, electric and diesel face equipment: including haulage equipment such as shuttle cars. There are nine basic types of panic bars (and several variations) that arc recommended in this document, but all of the panic bars are characteristically of the "fire door" type that is frequently encountered on outside exit doors of many public and some commercial buildings. It is also the intent of the following panic bar designs that, when emergency brakes are added to the face equipment machinery for which they arc required, that they be designed and hooked up so that actuation of the panic bar will result in automatic application of the emergency brakes (immediately following the deenergization of the tram motors). The following panic bar design requirements are a restatement of the proposed requirements defined in the Federal Register, requirements cited in "Guidelines for the Design and Installation of Devices for Deenergization of Self-Propelled Electric Face Equipment/Automatic Emergency Brakes" by C. E. Lester and J. D. Greenhalgh of MESA, and Bendix recommendations that were formulated as a result of discussions with personnel al the various machine manufacturers and underground coal mines that we surveyed, discussions with G. L. Judy (our consultant), etc:

Jan 1, 1974

Jan 1, 1967

By Christoph Mueller

Broad band mine communication today is characterized mainly by individual solutions, which have in common their long development phases and their high cost for development, operation and service. The use of Ethernet and TCP/IP on the other side provides an uniquely price efficient combination of high bandwidth open networking, universal use and accessibility of cheap development tools, especially because it forms the technical infrastructure for the worldwide Internet. TCP/IP and Ethernet assures reliable networking however it is not able to guarantee the latency timing of forwarding network information. Therefor, the network design requires strict load limitation and application level traffic control especially if moving equipment has to be manually remotely controlled via the network. To optimize the use of bandwidth on mining networks using load limited, ?bandwidth wasting? local Ethernet segments, long distance broadband traffic should be carried out using more efficient, deterministic communication backbones providing a guaranteed quality of service for each of the physically separated networks. Open networking and broadband systems however may lead to the anticipation that any demands on bulk data or multimedia traffic can be fulfilled in the future. This definitely will not be the case as the bandwidth demands of applications will be growing as least as fast as the bandwidth provided by communication systems. Looking on those problems from an overall system integration perspective, machines and equipment in the future have to be equipped with intelligent computing devices capable of an intelligent local data preprocessing. Such ?Embedded Machine Information Servers? running commercial computing power in the future will be the intelligent bridge between open networking and a secured, high safety local automation system. These ?Embedded Machine Information Servers? then also can make advantage of intelligent video and audio data preprocessing to store and transmit multimedia information ?on demand? or when the application requires it. Summarizing the potential for the future Ethernet based networking together with powerful communication backbones and intelligent local data preprocessing on the machines in the future will lead the way to integrative, reliable and cost efficient mine automation solutions.

May 1, 2002

By S. D. Botts, F. Cantuarias

"The Antamina project, owned by BHP Billiton Plc, Mitsubishi Corporation, Noranda Inc., and Teck Cominco Ltd., is a $2.3 billion copper/ zinc project, located in the Ancash Department of Peru. The project consists of an open pit mine, a 70 000 ton per day concentrator, a 302 km long concentrate pipeline, port facilities, a new access road, power line, and town site. The project is designed to produce up to 1.5 Mtpy of copper and zinc concentrates over a 23 year project life, and will be the third largest producer of zinc and the seventh largest producer of copper in the world.This mega project is the largest mining investment in the country and, during its construction stage, was the most important construction project worldwide. On May 28, 2001, Antamina commenced testing operations and four months later, it reached commercial production. Antamina was officially inaugurated on November 14, 2001 by Peruvian president Alejandro Toledo.The construction stage of the project generated 8000 direct jobs, with a peak of 10 000 employees, and 30 000 indirect jobs. The permanent workforce consists of approximately 1650 employees, the vast majority of which are Peruvian Nationals, around 30% of whom came from the region where the deposit is located. Approximately 5600 indirect jobs were generated from the project. Independent sources state that Antamina increased the Peruvian mining exports by 30% (mining exports constitute 50% of Peru’s total exports) and Peruvian GDP by 1% in its first year of full operation in 2002.Since winning the privatization bid for the project in 1996, the company has implemented an approach to community development and environmental protection based on sustainable development principals. Throughout the development of the project, a number of initiatives have been undertaken to ensure full involvement of the local populations in community development activities and the company’s environmental program.Due to its size, difficult logistics, cultural considerations and financial aspects, the project has faced a number of unique challenges in the area of environmental protection and management of community interaction. Antamina has been innovative in its approach to these issues and, as a result, has set new standards in Peru for environmental and community management and sustainable development."

Jan 1, 2003

By K R. Brentley

"Tshepong Mine, Harmony’s largest gold producing mine, is situated in the Free State portion of the Witwatersrand Basin, east of Odendaalsrus and north of Welkom, South Africa. The Basal reef is a narrow tabular conglomerate and is the main gold bearing ore body. The strata strikes mainly in a northsouth direction with an average dip of 22 degrees. Currently mining takes place at depths of between 1 690m and 2 150m below surface. The Basal reef unit consists of a conglomerate ranging between a few and 30cm in thickness. Some 80-90% of the gold occurs in the lower portion of the conglomerate. Directly above the conglomerate is a quartzite placer unit, the Basal quartzite, which is a clean, hard competent rock and varies in thickness between 50cm and 200cm. The Basal unit is overlain by the Khaki shale which can vary between 30cm and 500cm in width. It is weak and incompetent khaki coloured chloritic shale.A method of stoping, termed “undercut”, is practiced in order to remove the lower 15-20cm of the gold rich strata. The method entails removing this portion along with some 70-80cm of footwall host rock which is a strong competent quartzite. The hard competent quartzite overlying the conglomerate is left in-situ to form a competent hangingwall which can stabilize and prevent exposure of the weak Khakishale. This method of extraction was developed through trial and error and has been used reasonably successfully since its inception in the early 1960’s where the method was developed to extract the Basal reef at the Western Holdings Mines. Recently prospect drilling and a number of localised hangingwall failures indicated that the residual quartzite beam could be less than 60cm and in some instances as thin as 30cm in certain areas of the mine. The result of this is a less stable hangingwall which not only poses a safety risk to workers in these areas but also had the potential of locking up some 840 000 Tonnes of gold bearing ore. At the present gold price this amounts to revenue of approximately ZAR1.5 billion (U.S. $143 million).This paper discusses the method of “undercut stoping” and existing practices in place at Tshepong Mine. It also explores new initiatives such as the use of a simple freely-supported elastic beam solution to perform back analysis, on-site data capturing of beam thickness and support geometries in order to develop empirical design charts and numerical modelling to assist in the verification of the empirical design method."

Jan 1, 2015

By Ethan Steward, Kyle Perry

To test the effects of impact on mine seals, a projectile generator and two seals have been constructed. The projectile generator is a 12-inch (30.5 cm) inner diameter steel pipe with a 4-inch (10 cm) wall, is 8.5 feet (2.6 m) in length, and sealed on one end. Projectiles are propelled by a charge of black powder with a wooden wad and are held in place by foam sabots in the bore. This system, combined with the large bore, allows firing of many different potential projectiles that may be found in an underground mine at a high velocity into the seals.

Feb 1, 2020

By Amado Yataco

El presente texto describe el panorama de las inversiones durante el período 2008-2017 a través de tres períodos: 2008 Enero 2017; 2016 Enero 2016 y Enero 2017. De acuerdo a este contexto, las inversiones mineras declinaron sin un ingreso significativo. Sin embargo, dado el número de megaproyectos mineros de clase mundial y las reservas mineras se plantean algunas medidas que coadyuven a la más pronta recuperación de las inversiones en los dos rubros más destacados: Maduración, ejecución de proyectos y exploraciones.

Mar 1, 2017

By R. P. King

The MODSIM mineral processing plant simulator is used to find optimal combinations of target separation specific gravities in a typical modem coal washing plant. A plant that is set up with these optimal targets can deliver up to 10% more yield at the same ash content as the same plant set up with separation targets chosen by conventional methods. MODSIM is the only simulator currently available that can simulate the liberation of pyrite and other mineral matter during open-and closed-circuit grinding operations. The simulator can therefore be used to assess the benefits of grinding operations in the flowsheet.

Jan 1, 1997

By G. St. J. Perrott, N. A. Tolch

"The testing of explosives for permissibility for use in coal mines was begun by the technologic branch of the United States Geologic Survey in February, 1909, and continued by the United States Bureau of Mines from July, 1910; this testing has been carried on from year to year as the explosives were submitted by manufacturers. As a result of these many years of testing for permissibility a large amount of data has accumulated regarding the characteristics of permissible explosives. The manufacturer expects a sample of explosive submitted for test to meet the requirements for permissibility, otherwise the sample would not be submitted. However, in spite of the careful regulation and preparation of the formulas a certain percentage of explosives fails to pass the gallery tests. It is therefore interesting to note the proportion of failures at the gallery for a given composition of explosive. The fact should be emphasized that this discussion deals with all explosives submitted for test, both those which passed the tests and those which failed to pass. Explosives that failed to pass the tests were never designated as permissible explosives and have never appeared on any list of explosives permissible for use in coal mines.The Bureau of Mines classifies permissible explosives in two ways, according to the quantity of poisonous gases produced and according to the characteristic ingredient of the explosive.4 In this paper only two types of the latter classification are considered, as follows:"

Dec 1, 1929

By N. L. Wimmler

"INRODUCTIONSedimentary deposits of titaniferrous magnetite occur at various localities in the eastern foothills of the Teton Ranse in Deer Lodge County, Mont. The Choteau deposit was examined by a Bureau of Mines engineer in August 1942. An exploration project was recommended.Core drilling exploration was begun in June 1945; it was concluded in August 1945, Seventy-six holes were drilled. This report presents the data obtained by the Bureau of Mines exploration.ACKNOWLEDGMENTIn 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 contri¬bution 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 examination, performs the actual exploratory work, and prepares the final, report. The. Metallurgical Branch, R. G. Knickerbocker, Chief, analyzes samples and performs beneficiation tests. Both of these branches are under the supervision of Dr. R. S. Dean, Assistant-Director. The field work was supervised by Earshel W. Newman, engineer in charge of the Helena Field Office. D. B. Hoiekvam was the project engineer; he provided most of the data used in the preparation of this report."

Dec 1, 1946

By F. D. Fox

Abandoned mill tailings deposits can be found scattered throughout the Northern Black Hills of South Dakota, indicative of past mining activities that originated during the great gold [ERRATA SHEET RESTORATION OF GOLD MILL TAILINGS, BLACK HILL, SOUTH DAKOTA 84-119 F. D. Fox Under subtitle Prospects Related to Present and Future Tailings Disposal Practices, include reference No. 12 in paragraph seven after "construction of the Grizzly Gulch tailings disposal project,"12 Reference 12 should read: Jeffries, Lawrence F. and Tczap, Andrew, "Homestake's Grizzly Gulch Tailings Disposal Project," paper presented at 1978 International Mining Show, October 11, 1978.]

Jan 1, 1984

By Hiroyuki Sano, Chikabumi Yamauchi, Mitsuru Tanahashi, Toshiharu Fujisawa, Shin-ya Iwahori

"Pyrometallurgical process using Cu2O-based slag was proposed as a recycling process for copper scrap. However, it is difficult to remove nickel from copper by oxidative refining. Therefore, it is necessary to reduce the concentration of nickel in copper before the oxidative refining. In the present work, the copper enrichment stage in this recycling process, where copper scrap melt is separated into the Fe-C-Cu melt and the molten copper, was taken up and the compositions of both melts were measured. Based on the above results, the distribution ratios of nickel between the Fe-C-Cu melt and the molten copper were calculated. Furthermore, the optimum condition of copper enrichment stage was discussed from the viewpoint of nickel removal and copper recovery. The possibility of recovering 4N-purity copper by using this recycling process was confirmed.IntroductionRecycling is well known as a method for saving resources and reducing environmental damage. More than 99% of copper is used in metallic form - as metal or copper alloys[l]. High-grade copper scrap is directly re-melted and reused, while low-grade copper scrap is transported to copper smelters to be pyrorefined and electrorefined. Nevertheless, a great amount of copper is being stockpiled in the cities and should be recycled in the near future. At that time, the current recycling process will face new problems due to the increases in the recycling rate to the smelters. This includes insufficient combustion heat to melt copper scrap and ·almost no benefit in electrorefining because the scrap does not contain gold and silver. Thus, an alternative pyrometallurgical method for copper scrap refining will be required."

Jan 1, 2000

By Wenliang Cao, Jidong Li, Mingjie Zhang, Yiyong Wang

In CaC12-CaF 2 System, we studied the electrode process and discharge mechanism of preparation of Al-Ca alloys by fused salt electrolysis with CaO as raw material. The change of back electromotive force after adding CaO was measured by continuous pulse oscillograph method and the discharge process mechanism was also investigated by cyclic voltammetry. The finial results indicate that back electromotive force decreases by 0.6V after CaO of 1 % is added and there was a peak of oxidation current ahead of the potential at which the negative chlorine ions precipitated. According to thermodynamic calculation, it was determined that current peak was caused by the CO2 produced by 0 2 - ionic discharge due to CaO addition.

Jan 1, 2014

By W. D. Mcmillan

Kaolin, or china clay, is the term applied to a group of hydrous aluminum silicates. Because of its purity, light color, and refractory properties, kaolin is used extensively in the manufacture of high-grade ceramic wares and as a filler by the rubber and paper industries. Although there are numerous pottery and enamelware plants in Texas, and large rubber and paper industries; all of the kaolin used in these plants is from other States, There are two known occurrences of kaolin in Texas, namely, the Leakey deposit in Real County and the several deposits of the Medley district in southern Jeff Davis County. An investigation of the Mueller kaolin deposit in the Medley district was undertaken by the Bureau of Mines. Following an examination of this deposit by W. D. McMillan, engineer in charge of the Texas field office of the Bureau of Mines, a proposal was made to investigate the deposit by diamond core drilling.

Jan 1, 1949