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The Johnny Mercer lyrics 'You've got to accentuate the positive, Eliminate the negative, Latch on to the affirmative à' would best sum up the traditional approach to community relations in the mining industry. This '90s 'Public Relations spin' approach, usually backed up by scientific data, technical reports and graphs outlining risk probability and the impact potential on people and communities, is being challenged. Challenged by communities who have greater access to information, demand greater levels of transparency and corporate responsibility of large corporate operations and possess greater awareness of the communities they live in.   The growth of the environmental movement, of anti-globalisation, anti corporatism, apprehension of a large corporate's ability to deal with community issues, and a lack of faith in the abilities of regulators to regulate corporate activities, means our industry faces challenges on multiple fronts. It must now be able to address these from a personal/community perspective if it is to remain relevant within communities.   One of the keys to this is linking the internal activities and responsibilities to the externals concerns and demands for higher levels of operation and care.   This presentation draws on Corporate Public Affairs trends, functions and approaches and the application to External Affairs activities within Newmont Waihi Gold's operations in Waihi and regional exploration activities throughout the Hauraki Goldfields.   The approach presented works on the philosophy that communities don't necessarily have to like what we do, but should be able to identify and recognise the way in which we involve them in decision making, communicate our intentions and respond to issues.

Jun 1, 2010

By V. F. Parry

[Approximately 7-1/2 million tons of subbituminous coals are mined annually in Colorado, Wyoming, and Montana, of which 50 percent probably reaches domestic consumers. The moisture of these subbituminous coals is high, averaging about 25 percent when they are mined. The coals are non-caking end stack to a variable degree when exposed to normal atmospheric conditions. They are good domestic fuels, are considered to be smokeless in most furnaces, and have been used for many years in hand-fired domestic furnaces in which the practice is to employ large lutes for efficient combustion.]

Jan 1, 1941

By Gregory M. Dexter

Recent litigation in Pennsylvania between three coal-mining companies and a private water company resulted in the payment by the coal companies of the equivalent of about $500,000 to buy a new water supply to replace that which had been damaged by acid drainage from strip mining. An investigation of the relevant facts indicates that the water could have been treated by spending about $40,000 on equipment and $15,000 yearly for chemicals, labor, and power until the contamination could be reduced about 80 pct. The water company's supply, furthermore, had deteriorated largely by reason of dry weather before stripping was begun by the coal companies. Payment to the water company should not have exceeded $300,000 and could have been as low as $100,000. Strip mining of coal is common in Pennsylvania. The most important objection to it in Pennsylvania is generally acid pollution of runoff water. An outline of the methods, therefore, that could be used to reduce such pollution, to compare acid-contaminated waters, and to treat such waters to make them satisfactory for public and industrial use is worth-while. The watershed of the West P~M Water Co. covers about 4.5 square miles, 20 miles west of Pittsburgh, and has two 90,000,000 gal reservoirs sup- plying about 1,300,000 gal daily for public and industrial use of which 450,000 gal daily are for two railroads. The pollution arises from weathered derivatives of typical "Coal Measures"

Jan 1, 1949

By David White

This paper is the result of a comparative study of ultimate coal analyses made and published by the United States Geological Survey. This study, at first casually undertaken to devise an acceptable classification of coals based on chemical analyses, was continued in connection with a microscopic examination of a number of the coals. The initial comparisons, made from a relatively small number of analyses, not only confirmed a previous conviction that the elimination of oxygen incident to the development of a coal is economically far more important than has been generally suspected, but also showed that oxygen is very nearly as harmful as ash in coal. The immediate purposes of the present study were: (a) To determine more definitely, from a comparative examination of a large number of ultimate analyses, the relative importance of oxygen as an impurity in various coals; (b) to illustrate the transition between various grades of coal of similar origin-transition mainly due to progressive devolatilization, brought about more or less directly by dynamic influences; (c) to ascertain the relative proportions of oxygen, hydrogen, and carbon in coking coals, especially with reference to a theory tentatively framed to explain the coking quality; and (d) to forecast the probabilities of successfully treating a large number of coals so as to render them amenable, in a softened condition, to satisfactory study under the microscope.

Jan 1, 1911

By K. S. Raja, F. Battick, B. Pesic

"CeO2 doped with lower valence cations, such as Y3+, Sm3+, Gd3+ etc. is considered as electrolyte material for low temperature SOFC. Doping introduces additional oxygen vacancies and improves ionic conductivity. This work describes the preparation of yttria-calcia doped-ceria precursor material, its sintering in DC and AC field methods, and characterization of sintered electrolytes with respect to the ionic conductivity. Doped precursor materials were prepared by a controlled co-precipitation process. Sintering of prepared, pelletized particulates was carried out using three different methods such as: 1) conventional; 2) spark plasma sintering; and 3) an alternating current field at 1125°C (AC assisted sintering). The mechanism involved in the conductivity improvement as a function of defect density, grain boundary area and phase stability will be discussed. INTRODUCTIONThe performance of SOFCs depends highly on the properties of materials. Subtle variations in the composition, microstructure, or density of SOFC components can considerably alter the power output capabilities of fuel cells. Early SOFCs utilized zirconia based electrolytes but efforts in lowering the operating temperatures of SOFCs have prompted investigations into several other oxygen ion conductors – often modified with dopants to either promote the formation of oxygen vacancies or to stabilize a vacancy rich high temperature phase – such as bismuth oxide, lanthanum gallate, and ceria.The transport of oxygen ions through the electrolyte first begins with diffusion into the material. While this is generally a surface kinetics phenomenon, it is safe to say that it is highly dependent on oxygen pressure and vacancy gradients. The role of the cathode in SOFCs is to reduce oxygen at the electrolyte surface creating an O2– ion gradient which induces permeation into the material. Once inside and under the influence of a potential field, O2– ions migrate by a vacancy hopping mechanism, Catlow, C.R.A. (1990), effectively exchanging positions throughout the matrix until they reach the anode and react, thus leaving the matrix."

Jan 1, 2012

By Roger A. Dworak

This report describes in detail the work done on the development of the Time Domain Reflectometry Microcomputer (TDRM). Modifications to the FMC-Model 302A Cable Fault Locator is described in Appendix D. The TDRM unit uses an 8080 microcomputer to accurately locate major faults in low capacitance cables to within ± 1 foot when properly calibrated. Major faults in high capacitance cables are usually located within ± 5 feet. The upper limits of fault detection are <1 kilohm shunt fault and >7 ohm series fault. In practice fault detection limits are reduced to <300 ohms shunt fault and >30 ohms series fault because of discontinuities caused by cable repair.

Jan 1, 1977

By CH. Liu, H. X. Jiang, X. Xiao

"A study has been conducted to characterize the fatigue life in 7050-T7451 thick plate by the comparison between an experimental alloy and commercial alloy. The fracture origins were specified and their sizes were measured by scanning electron microscope (SEM). Additionally, the size, number density and spatial distribution of porosity in the experimental material and commercial material were characterized and compared, using X-ray Computed Tomography(XCT). The results showed that microporosity was the predominant site for crack nucleation and subsequent failure of the experimental alloy. However, as for the commercial alloy, fatigue cracks were found to originate from constituent particles. The presence of microporosity in 7050-T7451 thick plate reduced fatigue life of an order of magnitude or more compared to the commercial alloy. The relationships between size of origin and fatigue life were proposed. It was showed that the fatigue endurance was reduced when the size of porosity increased.INTRODUCTION 7xxx series aluminum alloys, due to their combination of high strength, high resistance to stress corrosion cracking, and good fracture toughness, are widely used in structural engineering applications where high-strength and low-density characteristics are fundamental design requirements (Williams& Starke, 2003). Every designer is striving to find an optimal combination of properties including strength, corrosion resistance and fatigue resistance (Wanget al., 2016). Based on the design principles of aircraft, a higher fatigue resistance of aluminum alloys are required. Thus, many investigations have been carried out on the microstructures and its effect on fatigue properties of the 7xxx series aluminum alloy (Robson, 2004; Schubbe, 2009).Microporosity, which is a common defect in casting materials, can lead to a significant deterioration of mechanical performance and fatigue resistance, especially in the high alloyed 7xxx aluminum alloys. The actual valid loading area decreases due to microporosity, which results in detrimental effect on the mechanical properties. Many experimental studies have been conducted in this research field. Mayer et al.(2003) investigated the fatigue properties of magnesium alloys produced by high-pressure die-casting. The results show that porosity in magnesium alloys greater than0.18mm diameter may be considered as the most important material defect for high cycle fatigue and fully reversed loading conditions. Nadot et al.(2004) found that the near surface defects are much more dangerous than the internal defects. Wang et al.(2001a) used the Weibull statistics method to analysis the influence of the microporosity, oxides and particles on the A356-T6 alloy fatigue life. The results show that, the porosity is more detrimental to fatigue life than oxide films and particles. With regard to fatigue resistance, although the deleterious effect of microporosity has been generally acknowledged, a quantitative understanding between casting microporosity and fatigue life in 7050-T7451 plate is not well established."

Jan 1, 2018

By D. Harrington

Every few weeks United States newspapers of 25 or 30 years age ran scare-heads telling of some mine disaster, which was a first-page attraction for a day or two and then was forgotton until another disaster occurred a few weeks later. Interspersed with these disasters were the so-called sniping mine accidents, causing the death of one or two mine workers. The summation of all types of mine fatalities usually exceeded 3,000 a year. In the period 1906-10, inclusive, there wore 84 major explosion disasters (or about 17 per year) in united States coal mines; the fatalities resulting from those disasters numbered 2,388 for the 5-year period. These frightful catastrophies helped to cause the total number of fatalities in our coal mines for the 5 years (including the fatalities from major explosions) to reach the enormous total of 13,288, an average of 2,658 per year. In addition, some hundreds of other typos of mining accidents swelled the annual fatality list to upwards of 3,000. This admittedly deplorable condition created so much Nation-wide comment that Congress was impressed with the necessity of having something done by the Federal Government with a view to trying to halt at least sonic of the excessive loss of life in our mines; in consequence, the Bureau of Mines was created and began to function in July 1910.

Jan 1, 1935

By Chris Nelson

Two pieces of European Union (EU) legislation together establish requirements for protection against risks from vibration at work. The vibration directive1 specifies duties of employers to protect workers from risks from exposure to vibration; the machinery directive2, specifies duties of manufacturers and suppliers regarding the safety of machinery marketed in the EU. This paper discusses both directives and the standardisation programmes that support them. It also addresses the implementation of these requirements in Great Britain. Employers’ duties: the vibration directive This directive requires employers to assess and control risks to health and safety arising from hand-arm vibration (HAV) and whole-body vibration (WBV). Member States were required to implement the directive in national legislation by 6 July 2005. Employers are required to eliminate vibration risk at source, or reduced to a minimum. The duties include: assessing risk and exposure; planning and implementing the necessary risk control measures; providing and maintaining suitable work equipment; providing workers with information and training on risks and their control; and monitoring and reviewing the effectiveness of the risk control programme. Daily exposure exceeding a specified action value triggers a requirement for a programme of technical and organisational measures to minimise vibration exposures and the resulting risk, and the provision of health surveillance. Exposures above a specified limit value are prohibited. When conducting their risk assessments, employers are required to “assess and, if necessary, measure” the vibration exposure of workers, for comparison with the action and limit values. Vibration measurement in the workplace is not expected in all cases and the use of vibration information from equipment manufacturers is specifically mentioned. This provides a link with the machinery directive (see below). Manufacturers’ and suppliers’ duties: The machinery directive The machinery directive, first introduced in 1989, is intended to remove barriers to trade. It puts duties on manufacturers and suppliers who place machinery on the European market to design their products to eliminate or reduce risks to health and safety and to warn the user of any residual risks, providing information required for safe use (for example, operator training, maintenance and selection of consumables). There are specific requirements for minimising risk from vibration in the design and construction of the machine and, in the case of hand-held, hand-

Jan 6, 2006

By James N. Bayne

An examination and analysis of Landsat digital data in the monitoring of surface mines in selected counties of South Carolina.

Jan 1, 1979

By E. Swartzman

This paper presents a general re-view of the various methods of briquetting coals, with and without the aid of a binder, with special reference to the production of a suitable briquette from Nova Scotia 'fines' for re-blending with industrial coal. From the economic and technical viewpoints, either small stoker-sized briquettes made with about 4 per cent asphalt in standard low-pressure double-roll presses, or briquettes made without binder in high-pressure double-roll presses, appear to be the most reasonable solution at present.

Jan 1, 1959

By D. Gu, R. G. Anthony, C. V. Philip, M. E. Huckman

"In this paper, we review the equations needed to construct an ion exchange column model. These models contain three major components: 1) a differential material balance around the column, 2) a differential material balance around an ion exchange particle, and 3) a constitutive equation for diffusive flux. We then examine the ability of a fairly simple mathematical model to predict ion exchange column experimental data. This model contains the traditional absorption theory equations and is used to predict the behavior of a column filled with a hydrous crystalline silico-titanate and which is removing trace amounts of Cs+ from a high pH, complex electrolyte solution. Finally, we propose replacing Fick's law with the Nemst-Planck equation as the constitutive equation for diffusive flux. We use a NemstPlanck type model to predict batch experimental data, then evaluate it by comparing it's ability to predict experimental data to that of a more traditional Fick's law type model. The data from this comparison suggests that the Nemst-Planck type model yields better results.IntroductionMillions of gallons of strongly basic, radioactive waste are currently stored in underground storage tanks at Hanford and Savannah River and several locations within the United States. Due to the limited life expectancy of the tanks, there is a pressing need to remediate these wastes. This need has prompted the recent development of new ion-exchange materials for removing radioactive elements from aqueous solutions. A novel material called TAM-5 has been developed jointly by Texas A&M University and Sandia National Laboratories. TAM- 5, a crystalline silico-titanate, is highly selective for Cs + in the complex electrolytic solutions typical of these wastes. It is stable in very basic solutions and in radioactive environments [1, 2 ,3]. In laboratory testing to determine the selectivity of various materials, TAM-5 was superior to other candidate ion exchangers [4, 5]. The selectivities were determined by measuring a distribution coefficient, Kd, which is defined as the concentration, gig or mmols/g of Cs in the solid phase divided by the concentration, mg/L or mmols/mL, of Cs in the liquid phase. The units of Kd are ml/g or L/kg. Table 1 shows Kd values for TAM-5 compared to 9 other candidate materials in a typical waste solution [6]."

Jan 1, 1996

By M. E. Coleman, G. Money

Pneumatic Conveying and Process Injection Technologies have been implemented in the metals markets for the last 40 years and have considerably improved the productivity and the performance of many processes. There have been many steps forward in handling technology and this paper seeks to consider those now offered by Clyde Materials Handling who as an established customer-driven solutions provider has turned its attention to supporting the Metals Market. Clyde seeks to utilise its knowledge, expertise and technologies to transform the production processes of its customers, who operate in the ferrous and non-ferrous metals industries.

Jan 1, 2008

By P. Mottahed, E. De Souza

One of the major unsolved problems of safe, economical roof support in the evaporite industry has been that of obtaining and maintaining anchorages in relatively soft rock. This is due to the viscoelastic and viscoplastic behaviour of salt rock and associated deposits. This paper introduces a low-cost, yieldable support mechanism, consisting of a system of buckling disks, which provides viable solutions to dynamic support. The yieldable support system offers a number of advantages in comparison with existing dynamic support systems. It is characterized by its simplicity in design and installation, repeatability in behaviour and cost effectiveness. It also has the added advantage of providing the operator with a means of assessing support behaviour and ground performance by direct visual observation of changes in disk shape. Thus, the system can be utilized as a warning mechanism of ground stress and support load conditions. Such system not only provides a feasible and more effective rock mass stabilization strategy but improves mine safety.

Jan 1, 1999

By Malte J. M. Gurgel, Axel Preusse

Recent three-dimensional surveying techniques have opened up new opportunities for the registration and monitoring of underground cavities. There are essentially two main methods available: Laser scanning, which is used both above surface and increasingly underground, and photogrammetry, which is also experiencing a renaissance with techniques like structure from motion through the algorithm-based orientation of high-resolution images. Both methods provide the capability to reconstruct reality by various 3-D products like points clouds and meshed models. However, they differ significantly in the steps of registration and calculation as well as in the resulting evaluation options.

By P. R. Perry

This publication is a compilation of tested methods for the analyses of titanium tetrachloride, titanium sponge, and various intermediate materials and products. They are presented in concise form without the detail usually found in publication of new methods because many of them are modifications of well known procedures. The Electrometallurgical Experiment Station, Boulder City, Nev., has been developing titanium production methods since 1945. Most of this development was on a modified Kroll Process but also included work on sodium reduction and electrolytic methods. During these years a large variety of samples were analyzed. Most of the analytical problems were solved using published methods or modifications of the same. At the start, there were no published procedures for analyzing titanium sponge using spectrochemical methods. A great deal of study was given to testing several of the well known techniques, and some of them, such as direct sparking of the metal, proved to be completely unsatisfactory. Solution-spark techniques were finally tried, and satisfactory procedures were developed for some of the more common impurities. These spectrochemical methods were then put into routine use for several months before their publication.2/ Some new modifications have been made, and techniques have been developed to determine other impurities found in titanium sponge and tetrachloride. All spectrochemical methods used in 1954 are included in this publication.

Jan 1, 1955

By J. van Deventer

Volatile gold prices in the face of rising costs for mining and refining is causing the mines to look for new ways to reduce costs and increase recoveries. This task is complicated by the fact that the gold in hereto unexploited reserves is associated with increasingly complex ores - either preg-robbing, refractory, associated with high concentrations of copper, or all of the above. Ion exchange resins can play a significant role in this quest for improvement. Although ion exchange resins have been used in Former Soviet Union (FSU) countries for the recovery of gold for many decades, it is still not widely used in the Western World. Synthetically manufactured ion exchange resins can be tailor-made to suit the chemical and mechanical characteristics of a specific application. As such, ion exchange resins can be used in a variety of solution matrices (e.g. cyanide, thiosulphate and acid), and process designs (recovery from clear liquor after solid-liquid separation or directly from the leached pulp). In this paper, a number of applications are discussed along with a review of recent developments in ion exchange technology.

Jan 1, 2014

By Elisabetta Tedeschi, Razieh Nejati Fard

Deep-sea mining is in the future perspective of mining industry and it is currently in the technological development phase. The focus of this study is on the electrical power system that provides sufficient energy for the mining equipment at the seafloor, excavating Seafloor Massive Sulfide (SMS) deposits. SMS deposits usually exist at water depths between 1500 m and 4000 m. Despite the similarities of SMS deposits excavation to the open-pit terrestrial mines, more energy is required to drill and crush the ores in the hyperbaric conditions [1], which can be done whether by static trench cutters [1] or by mobile mining crawlers [2]. In addition, the ores vertical transportation by subsea pumps requires several MW electrical power that can be supplied by all-electric subsea motors or hydraulically from water injection motors located on the surface. The power requirements can be fulfilled by an offshore or subsea power network. As the SMS mines are usually in remote locations, the straightforward solution will be an isolated offshore grid mounted on a vessel or platform similar to the most of offshore Oil & Gas projects. These power systems resemble the onshore microgrids for industrial purposes operating in island mode. However, in contrast with the onshore power networks, there are space and weight limitations in offshore infrastructures, which impose the design compactness to be a priority. In addition, having a very high reliability is necessary in the design approach of the offshore projects due to the extraordinary high expenses corresponding to repair and maintenance. The other design criterion is to improve the power system efficiency in order to reduce the size of the power equipment cooling apparatus, operational costs and CO2 emissions produced by diesel/LNG onboard generators. There are a few studies considering power system distribution for seafloor mining industry. Among them, [3] has investigated the AC and DC alternatives for SMS mining in 2400 m water depth by considering Solwara 1 project scenario introduced by Nautilus Minerals Inc. [2]. In this study, a power system design tool will be presented taking into account various water depth, power consumption levels, different distribution configurations (AC and DC) and the aforementioned design criteria.

Jan 1, 2018

By A. U. Christensen

THERMODYNAMIC data for many of the common interoxidic compounds are seriously lacking, and appraisal of possible ceramic or metallurgical applications depends upon dubious estimates. In particular, high-temperature heat-content estimates may be invalid because of unknown phase-transformations. This paper reports experimental heat-content values above 298.15° K. for five interoxidic compounds-the aluminates of lithium and sodium (LiAlO2 and NaAlO2), the ferrites of lithium and sodium (LiFeO2 and NaFeO2), and lithium titanate (Li2TiO3), as obtained by the Bureau of Mines. Sodium aluminate, sodium ferrite, and lithium titanate were found to have previously unknown transformations in the crystalline state. The heats and temperatures of these transformations were evaluated as were also the heats and temperatures of fusion of sodium ferrite and lithium titanate. The heat-content results are assembled in both tabular and algebraic-equation form for use in conducting thermodynamic calculations at temperatures in the range 298°-2,000° K.

Jan 1, 1960

By S. A. Hovanessian

The method of characteristics which reduces the Buckley-Leverett mnlineur, partial differential equation to two first-order, linear differential equations is applied to the solution of a waterffood recovery problem for multiple lines of producing wells and one line of injection wells. The application of the method is described by a numerical example, and a brief theoretical background is given. From the results of this study, it is concluded that the cumulative water injected and oil produced are the same for single and multiple sets of producing wells. INTRODUCTION In this paper, the method of characteristics is applied to the solution of a waterflood recovery problem with multiple lines of producing wells and one line of injection wells. The application of the method to this type of recovery problem considerably simplifies the procedure of obtaining a numerical solution. It differs from the method described by Kern1 because it eliminates the need for integration in obtaining saturation fronts. In addition, the saturation history at any location within the field is obtained from a single diagram (time vs distance with saturation as a parameter)&apos;. The paper includes a brief theory of the method of characteristics and its application to the solution of oil recovery problems. A numerical example is worked out, and the cumulative oil recovery-vs-time curve for a system with multiple sets of producing wells is obtained. This curve is then compared with the recovery curve of a system with only one set of producing wells. From this study, it is concluded that the cumulative water injected and oil produced are the same for single and multiple lines of producing wells. However, the recovery time is considerably longer for multiple sets of producing wells.