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By Clyde N. Garman

Historically, Vanadium and Uranium have been precipitated together in carbonate sill circuits. A separation of the salts of the two metals was then made on the basis of the fact that the reduced, salts of vanadium are more solo to and those of uranium lose soluble than the respective salts of higher valence. In practice this was carried out by fusing the precipitated combined concentrate with salt, sodium carbonate and sodium hydroxide with oil soaked sawdust mixed into the charge as the reducing agent. Generally the fusion was carried out batch wise and the resulting slag or glass leached in water. A good, fusion and three or four decantation washes resulted in almost complete recovery of the vanadium in the liquid phase and a very high recovery of the uranium as a dense black U02 solid.

Jan 1, 1962

By J. Partyka

Fumes produced during blasting operations in underground mines are defined in this paper by an equivalent contaminant source. The primary goal is to establish a method which would allow all those parameters not measured directly to be determined reliably from field data. The parameters to be identified are the diffusion coefficient , and the position and size of an equivalent source. The diffusion-value is computed from the peak concentrations taken by two monitors located in the drift. The first monitor is placed close to where blasting pollutants join the main stream, while a second monitors is moved downstream a some distance from the first point. The position and size of the dust source and the total amount of dust produced during blasting are determined from the data recorded by only one monitor.

Jan 1, 1991

By G. A. Doyle

The quality of water in mine pit lakes depends in part on the physical limnology (Le. stratification, turnover, and development of anoxic conditions with depth) of the lake. Limnologic data collected from four existing pit lakes indicate that pit lakes develop a thermocline, or temperature stratification, in the upper 10m to 30 m of the water column. Two of the pit lakes (26 m and 55 m deep) undergo seasonal turnover of the entire water column, whereas two deeper pit lakes (110 m and 240 m) undergo seasonal turnover of only the upper portion of the water column. In the deeper lakes, seasonal mixing does not extend through the entire water column and a distinct chemocline develops with depth.

Jan 1, 1996

By D. Loy LeRoy

As we are all aware, the impacts of the 1977 Surface Mining Act and the implementing OSM Regulations require application of new, as well as existing, equipment and technologies. Our firm recently completed (June, 1979) a study for the Department of Energy titled "Analysis of the Impact of Public Law 95-87 on Mining Performance." The objective of the study was to analyze the impact of the Act and its regulations on mining performance in order to provide recommendations to alleviate the impacts identified, including identification of research needs. This paper presents some of the highlights of that report: projected cost increases; additional equipment needed for compliance; review of methods currently practiced or those which can be modified; and will focus particulary on equipment and technology applications.

Jan 1, 1980

By Hetland Donald L.

Regional Tertiary formations and basins of local sedimentation which contain uranium deposits west of the Rocky Mountains are mainly of Oligocene, Miocene, and Pliocene age (fig. 1). The host rocks have been derived mainly from intrusive and extrusive igneous rock. The major host formations which cover broad geographic areas include the Esmeralda, Truckee, Humboldt, Thousand Creeks, Payette, Panaca, Cedarville, Coso, and San Joaquin Formations. Local areas of Tertiary sedimentation containing uranium deposits occur near Yuma, Safford and Artillery Peak, Arizona; Dillon and Canyon Ferry, Montana; Spokane Indian Reservation and Pend Orielle River, Washington; Topaz Mountain, Utah; Stanley Basin, Idaho; and Sonora Pass, California. Uranium deposits in these sediments have been classified into five categories based on environment (fig. 2). They are: (1) Deposits in lake sediments consisting mainly of water-laid tuffs; (2) Deposits in lake sediments intruded by volcanic plugs; (3) Deposits in lake sediments interbedded with arkoses near batholiths; (4) Deposits in coarse volcanic sediments in local sedimentary basins; (5) Deposits in arkosic conglomerates in local sedimentary basins.

Jan 1, 1969

The 1997 Rapid Excavation and Tunneling Conference (RETC) was held at the Mirage Hotel, Las Vegas, NV. The RETC is a biennial event jointly sponsored by SME and the American Society of Civil Engineers (ASCE). Conference attendance was 573 members, nonmembers and students, an increase of seven attendees from the 1995 conference in San Francisco, CA. Exhibitors occupied 51 booths at the Las Vegas RETC. The 1997 conference encompassed 58 presentations in 15 sessions. Participants were given details on achievements and advances that have resulted in new design solutions, alternative work practices and increased productivity within the industry. The page at the end of this article tells how to get your copy of the RETC proceedings, either hardbound or on CD-ROM. Or, if you wish, for the first time a CD-ROM is available with the complete RETC proceedings from 1972 to 1997. This two-disk, archival volume has key-word search capability, is in portable file format and is compatible with PC and Macintosh platforms. RETC program sessions included design and planning, ground support, tunnel boring machine (TBM) case histories, conventional excavation, new technology, difficult ground, geotechnical, shafts and raises, future/special projects, new Austrian tunneling method, international projects, soft ground case histories and water and gas. What follows are highlights of some of the RETC presentations.

Jan 1, 1997

By L. H. Michaud

An existing mining company plans to extend their surface coal mining operations in central Pennsylvania. Although the proposed site contains pyritic material, the results of the acid-base accounting for the site show an overall NP:MPA ratio of 4.26:1 for the entire site. The pyritic material is, however, associated with the lower of the three seams to? be mined. If traditional dragline mining methods were used, this would result in the acidic material being placed at the top of the spoil piles, exposing it to air and water, and therefore to the formation of Acid Mine Drainage (AMD). Further concerns are associated with the fact that the alkaline material is not distributed evenly over the mine site. In order to prevent the formation of AMD, the company has proposed to mine the area using Truck/Shovel mining methods. This technique offers a more flexible alternative for cut sequencing and for the selective placement of waste material. Working with the Department of Mineral Engineering at The Pennsylvania State University, a mine plan was developed for this site. This plan results in the layering of the alkaline and acidic spoil in order to achieve an overall net alkalinity in all spoil areas. Mining of this site should therefore not result in the formation of AMD.

Jan 1, 1994

The structure of a mine ventilation network (M.V.N.) can be represented graphically using either the mine plan (map) itself or a number of other types of diagrams. In the U.S., the two most common approaches are the line and the schematic diagrams (see Figures 1 and 2). The purpose of this paper is to introduce another type of diagram, called the canonical diagram (6). The method of M.V.N. representation which uses canonical diagrams is used extensively in Europe, and especially in Poland, where it was developed. The canonical diagram is a noncalibrated topological image of a ventilation system. It gives a simple representation of the ventilation network, allows for the classification of currents within it and enables rapid computer analysis and computation, as well as the representation of the results. It is especially useful in studying and controlling the air flow, and it may be a life saving tool in conducting rescue operations during and after mine fires.

Jan 1, 1986

By w. Chruscielewski, T. Domanski

INTRODUCTION Concentration of radon 222Rn and its decay products occuring in the Polish mines of metal-ores call for the necessity of systematic radiation control /Do8la/ both of the working environment and of the miners' personal exposure. The attempts at introducing a system of radiological protection in mines, similar to the ones existing in X-ray or isotope laboratories, took several years and consisted of development of the methods for control of concentration of radon and its progeny in the air, as well as the methods for measuring individual exposure. It was accepted that the assessment of both transient concentration in the air and of personal exposure are basic elements of the control system, which should be implemented independently of each other. Concentration measurement serves to detect and to determine those areas in mines where there is intensive radon emanation, and where current control of the effectiveness of technology introduced to deacrease the concentrations is necessary; personal dosimetry results in the assessment of the actual exposure of miners to radiation. PRINCIPLES OF THE SYSTEM The assessment of working environment is based on concentration measurements of the potential radiation energy of radon alpha decay products. Decentralized assessment is carried out by the special dosimetric service operating in each mine. Dosimetrists are equipped with portable radiometers, type RGR-11, made by the institute of Nuclear Research, Warsaw. The radiometer is presented in Fig. 1. Measurement of filter activity is performed automatically according to Markov's method /Ma62/ or any other method. Simultaneously to potential energy measurement the dosimetrists are measuring the dust concentration in the air and ventilation rate. Ventilation service looks for correlation between those indices and the concentration of radon daughters in the air. Derived Air Concentration /DAC/ for concentration assessment was accepted to be 6.25 10-6 Jm-3 /0.3 WL/ according to ICRP recommendation /Publication No. 24/ /ICRP77/. If environmental measurements reveal potential energy concentration exceeding the value of 0.3 DAC at working places, the miners employed there are subject to individual control of personal exposure. Individual exposure measurement is carried out centrally by the Institute of Occupational Medicine in [Lodz] for all metal-ore mines. Miners who are to be included in the control scheme are referred by a mine management to the Institute where they are registered and assigned a dosimeter. A passive dosimeter with

Jan 1, 1981

By R. Lawrence

Mineral property valuations to be used for Canadian securities regulatory purposes must comply with CIMVal1. The technical basis for a CIMVal report is the same as that required for a technical report that complies with NI 43-1012. NI 43-101 describes the content to be covered in a technical report, while also covering other requirements, one of which is that the report should be based on a property visit. CIMVal is based on five tenets that the valuator must follow: ? Materiality. ? Independence. ? Transparency. ? Competence. ? Reasonableness. Upon its adoption by CIM Council in 2003, it was hoped that the new CIMVal code would be adopted without change by the several Canadian regulators.

Jan 1, 2011

By Martin Valeri

The operation described in-this paper will be confined to the Nemacolin Mine of The Buckeye Coal company, Nemacolin, Pennsylvania.' This mine is-located on the Monongahela River approximately sixty miles south of Pittsburgh. The mining is in the Pittsburgh seam that has an average thickness of 88 to 90 inches. The current practice is to mine approximately 80 inches, leaving 8 to 10 inches of roof coal. All of the coal produced is used solely for by-product coking by the parent Youngstown Sheet & Tube Company, Youngstown, Ohio. Eight to ten inches of top coal are left by the miners to prevent air slacking of the draw slate. In addition, this top coal which will float at the washing gravity has a very high ash and sulphur content, and when mined, seriously affects the quality of the clean coal product.

Jan 1, 1961

By Richard F. Hammen

Mineral extraction from sulfide ore deposits usually leads to the combined action of oxygen and water on the newly exposed ore. The result is acid mine drainage, a low pH solution of various metal sulfate salts and sulfuric acid. Paradoxically, the valuable metals dissolved in acid mine water are a liability because they are too toxic for discharge but too dilute to recover economically. The expense of compliance with water quality release standards has reduced the profitability of many mining operations. Solid phase extraction (SPE) columns have been developed to extract metals from acid mine water. These columns are designed to remove the toxic elements from water and recover the metals as purified fractions. This article describes the results of a Phase 1 bench-scale project to test the performance of the SPE columns. The tests were conducted with water collected from the abandoned Berkeley Pit copper mine in Butte, MT.

Jan 1, 1993

By S. Rideout

The United States Department of the Interior's Office of Surface Mining (OSM) is responsible for regulating active coal mining and reclaiming abandoned coal mines in the United States. In working with the State government agencies that implement these programs, OSM is building a new approach that moves away from traditional "command and control" regulation and towards an approach that focuses on providing long-term environmental and economic sustainability on lands disturbed by coal mining. This initiative called "Reclaim the Future!" looks to enhance opportunities for economic development, wildlife preservation and enhancement, reforestation, and other beneficial and productive uses of lands disturbed by coal mining. The initiative is also focused on ensuring that the landowners and the local public have significant involvement in determining how best to reclaim mine sites and what post-mining land uses are most appropriate for each individual abandoned mine reclamation project or active mine reclamation. Through the use of the best scientific input in an open, participatory process, OSM hopes to further sustainable development principles for coal mining within the framework of existing United States law.

Jan 1, 2007

By R. E. Gertsch

Mechanical mining holds great promise for the mining industry. Realizing this promise depends on giving mine operators the capability to evaluate the higher production, the lower costs, and safety enhancement that comes with mechanical mining. The opportunities for low cost and high production must outset the high capital costs associated with mechanical excavation. Giving the mining industry the tools to effectively evaluate and successfully implement mechanical methods defines the challenges and directions of the mechanical mining industry.

Jan 1, 1994

By Leslie Burnside

Homestake Mining Co. set out to complete final reclamation at a former open-pit gold mine in west central Nevada. The goal was to exceed regulatory standards by satisfying the company's own high corporate standards for successful reclamation. Homestake's completion requirements challenged available technology due to the unsuitability of heap material as a growth medium, the harsh environmental conditions of the site and the region's lack of native growth medium. Accomplishing these goals required enlisting a multidisciplinary project team to develop, test and implement appropriate and cost-effective revegetation alternatives.

Jan 1, 1999

By Yanan Zhang, Hongwei Deng, Feng Gao, Bo Ke

Recently, liquid carbon dioxide (L-CO2) blasting technology has attracted attention due to its good fracturing effect and safety performance, especially in coal seam permeability improvement. This paper analyzes the blasting effect of L-CO2 based on experiments and studies the fracturing mechanism from the perspective of stress wave action via theoretical analysis and peridynamic simulations. The results indicate that L-CO2 blasting achieves a good fracturing effect without forming a crush zone, and the loading rate and strength of the stress wave are key factors.

Jan 19, 2022

By E. F. C. Ferrett

The benefits derived from the use of main fan evasees or diffusers are well known. If a well designed evasee is fitted to a fan either more air will flow through it or the same air flow rate will be discharged at a lower fan speed. This latter possibility will reduce the air power requirement of the mine, the fan input power and the overall energy costs. Despite these apparent advantages, many reports have been received from the industry of poor evasee performance. After examination, it appears that these problems are often caused by installation difficulties or inaccurate design procedures. The performance of an evasee is affected by several independent factors. Some of these factors describe the evasee geometry whilst others are concerned with the behaviour of the air as it passes through the evasee. This paper shows that the divergence angle is by no means the only ;important parameter which affects evasee performance and that the size of the inlet boundary layer has a significant influence. The performance of evasees of differing geometric shape are compared and the criterion to be used for optimum performance is discussed. It is shown that the commonly used evasee efficiency is a poor indicator of good performance. Recent work by the author and others is evaluated and a simple design. guide discussed. For more sophisticated work, details of a. computer program are provided. Finally, a brief resume of the performance of truncated diffusers is given. Since compressibility effects can be ignored for most mining applications, incompressible flow has been assumed for most of this paper.

Jan 1, 1980

By Dan Martz, Bill Moler, David Young, Wally Chen, Matthew Crow, Steve Norris, Tolga Togan

Two 610 m (2000 ft) long tunnels were driven through water bearing silts, sands and clays beneath the Sacramento River using a 4.59 m (15.1 ft) diameter Earth Pressure Balance Tunnel Boring Machine (EPBM). Four sheet pile shored shafts were sunk with and without dewatering. The pre-cast concrete segmentally lined and grouted tunnels were driven down at 6% grades beneath the river flood protection levees, buildings, roads, a railroad and adjacent to a Freeway Viaduct. Details of the schedule, cost, shaft construction, TBM, tunnel construction, and installation methodology for the twin1.676 m (66 in) steel force main pipes and environmental constraints are provided.

Jan 1, 2007

By D. P. Patil, B. K. Parekh

Water is the mainstay for beneficiation of fine size coal and minerals; however, it is also the least desirable constituent in the final product. The basic concept of the novel process described in this paper is based on the differential surface heat conduction/ absorption capacity of individual particles, which differs for different species of minerals. When a mixture of fine material is exposed to a radiant energy source, the various solids present in the mixture will absorb heat energy depending on their heat-conducting properties and there will be a difference in the surface temperature of the particles. When this differentially heated solid mixture is placed on a moving belt, which is coated with a low temperature melting resin, the hotter component of the mixture will stick to the belt and relatively cooler particles will stay free on the belt and fall off at the end of the belt run. Experiments were conducted with pyrite, coal, and quartz of 6 × 18 mesh particle size. The goal of the test program was to find the optimum conditions at which there exists a required temperature difference between minerals and coal particles by controlling the operating system variables. Preliminary tests results showed that there is a potential for separating mineral matter from coal using the thermo-adhesive separation technique.

Jan 6, 2022

By F. Habashi

Japan was a closed society until 1853 when it was forced to open to the West. Mining, metallurgical, and geological education started there around 1861 when a graduate from Yale University in USA went to Japan to organize the first School of Mines. This was followed by other metallurgists from Great Britain, France, and Germany and thousands from other disciplines. The present report is a summary of the writer's first contact with Japanese metallurgists and his visits to a number of universities and research institutions in the past years.

Jan 1, 2012