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By John J. McCrone

In the Mining Industry, the means of handling and transferring lubricants has been given little attention over the years. An analysis of this process indicates that this neglect has often exacted a very high price. As the costs associated with labor, equipment utilization and waste disposal soar, the need for an efficient system takes on an increasing significance. Often the focus of bulk systems has been placed on the master container itself. Certainly, there is nothing new about a large lubricant container; they have been available over a period of years, known under a variety of names, "mini tank", "super drum", ?flo-bin" and "tote bin", to name but a few.

Jan 1, 1982

By Patrick M. Hurley

The spreading-ridge, or accreting plate margin, is the primary conduit of metals delivered to the earth's surface. Isotope ratios of lead show primitive mantle values at these sites, indicating that this is true. We can use lead isotopes in any mineral deposit to indicate the degree to which the metal is "primitive" in the sense of having been uncontaminated with U-enriched crust or "crustal" in the sense that it has been cycling at the earth's surface since earlier times. The reason for this is that the upper continental crust has an enrichment in the ratio of U/Pb over that in the mantle, so that old continental leads have a larger radiogenic component. The primitive metals delivered to the surface at the spreading-ridge are transported on the oceanic plate until they reach a subduction zone. Here they become cycled in the "orogen". However, in this process the primitive metals are mixed with metals from the continent so that the average lead isotope ratios are between those in the mantle and the average upper continental crust. Subsequently a part of the metals in the orogen may become fixed in a new block of continent. However there are processes which continue to uplift and erode ancient continental regions so that there is a continuous feeding back of metals to the orogen. We have therefore a cycling of metals from the existing continental crust into the orogen where they are mixed with new contributions from the spreading ridge and mantle.

Jan 1, 1977

By David M. Spatz

Team, as defined by Katzenbach and Smith (1993), is a small number of people with complementary skills who are committed to a common purpose, performance goals and approach for which they hold themselves mutually accountable. As the mining industry searches for new ore discoveries increasingly under post-mineral cover, the process of mineral exploration has taken us from prospector to geologist to multidisciplined explorer to multi-disciplinary team. Multidisciplinary exploration techniques have improved in terms of sensitivities and penetration and more than ever before each technique requires specialists with appropriate training and skills to process data and interpret results. To produce a quality product, specialists must collaborate openly and honestly in an atmosphere where the collective result takes into account the knowledge and expertise of each individual and the relationships between all pertinent data sets.

Jan 1, 1998

By Ulf Marklund, Manfred Lindvall

Fighting the challenge of diminishing ore grades, low base metal prices and a changing pattern of ore supply, Boliden has now taken the second generation of the fully­autogenous grinding concept on stream, Using new design and a highly-developed process control system the benefits of conventional two stage autogenous grinding technology are obtained with a wide range of ore types. The APC grinding system has been developed further. A new design of the Boliden Pebble Extractor together with an advanced control strategy make the performance of the APC concept superior to all other grinding systems with any ore quality. The capacity and simplicity of the autogenous grinding concept is equivalent to the best SAG installations but the operational costs are up to 25 % lower than for SAG or other primary ball or rod mill systems. The concept is as flexible as conventional crushing and rod mill installations but investment and operating costs are of the order of 25 % lower. Also, from the metallurgical point of view, the different types of autogenous grinding system outperform all other comminution systems including SAG. From 1989 to 1991 four fully autogenous grinding sections have been installed at various concentrators at the Boliden company. Old crushing plants and rod and pebble grinding circuits have finally been replaced by highly productive and cost-efficient autogenous grinding equipment. Significant savings in operational costs have already been reported. Power consumption and maintenance costs have been reduced significantly. Productivity expressed as milled tonnes per operator has been improved. Metallurgical results have developed favourably.

Jan 1, 1992

By R. Milici

Current federal and State coal assessments estimate resources in the ground, resources available for mining, and economically recoverable resources. None of these assessments predict the amount of coal that may be produced from an assessed area in the near future (~20 years). Predictive assessments of coal production would be based on an understanding of the regional coal geology (coal systems), potential demand, and knowledge of the mining history of the region. The output of the predictive assessment would be a supply curve – a probability distribution of the amount of coal expected to be produced from current and new mines during the assessment period. I

Jan 1, 2004

By Parris A. Lyew-Ayee

This paper is the first preliminary report on the bauxites and terra rossas of the Caribbean. It concentrates on the islands of the Greater Antilles, and for reference purposes the Yucatan Penin- sula is included. At this point, observations made in Jamaica, Haiti, and the Dominican Republic are compared with reported information on Puerto Rico, the Bahamas, Cuba, the Cayman Islands, and the Yucatan Peninsula with regard to occurrence, as well as physical, chemical, and mineralogical composition. From this, an attempt is made at classifying the types of bauxites in the Caribbean, indicating the best reserves estimates, and the process ability of these bauxites. Some suggestions are also provided to fuel the controversy over the likely source material(s) or origin of the Caribbean bauxites.

Jan 1, 1984

By Angela K. Braden

Igneous rock exposures occupy only a minor portion of surface area (<18 mi2) in Arkansas, and are divided into two major groups: nepheline syenite (7 mi2) and syenite complexes (8 mi2), with various dikes and sills representing the remaining surface exposures. The syenite complexes have been the sites of major vanadium and minor titanium production during the past 50 years. Nepheline syenite exposures were important in the early production of locally used building stone; however, aggregate and roofing granules have now become the principal market for the production of nepheline syenite in Arkansas. Nepheline syenite intruded into a sequence of Paleozoic sedimentary rocks in Arkansas and is exposed in two areas: in Saline County near the town of Bauxite, and in Pulaski County at Granite Mountain, just southeast of Little Rock. Although the central Arkansas region had been investigated thoroughly for bauxite by the early 1950s, the nepheline syenite resources of the region have yet to be evaluated systematically by the state. Arkansas nepheline syenite was evaluated for its ceramic uses in 1952. Some recent industry interest has revolved around its potential use as a sand-blast abrasive. The largest exposed areas of nepheline syenite, located at Granite Mountain, currently are being mined by the Minnesota Mining & Manufacturing Company (3M) and McGeorge Contracting (Granite Mountain Quarry). 3M has been in operation since 1947 and mainly produces roofing granules. A fine powder produced by 3M during crushing that is marketed under the name Donnafill? recently has seen use as filler in self-compacting confined construction and as an additive (frit) in common brick. Since the early 1960s, Granite Mountain Quarries has produced a variety of aggregates, ranging from riprap to industrial sand, and recently constructed a computerized hot-mix-asphalt production facility. Approximately 4.5 million tons and 1.2 million tons of syenite were produced from Granite Mountain and 3M, respectively, during 1979. No production values are available after this date; however, combined production from both quarries is estimated to be at least 6 million tons annually.

Jan 1, 1999

By B. Nyman

A lot of work is in progress to improve copper recovery by leaching-solvent extraction-electrowinning (L-SX-EW). At Outokumpu the focus of attention is on SX equipment development as a result of which a new mixing-settling technology, the Vertical Smooth Flow (VSF) has been introduced. Using helical stirrers in the VSF mixers a more gentle and uniform contacting can be obtained than in the mixing compartments of the low-profile design. The benefits of Outokumpu&apos;s new approach are an essential decrease in organic losses and in aqueous in organic entrainments. Separate pumping using a smoothly pre-contacting "Dispersion Overflow Pump" (DOP) is a key feature of the VSF design. The scale-up of this pump as well as the VSF mixers are shown to follow simple mathematical relationships which also have been confirmed by full scale experiments.

Jan 1, 1995

By Kenneth J. Reid, Marian S. Stachowicz

A preliminary evaluation of a new in-stream particle size analyzer has been carried out using materials obtained from a taconite plant in Northern Minnesota. Results are reported for bench scale, pilot scale and full scale tests, the latter being carried out in a taconite plant concentrator. The unit employs a novel scanning laser microscopy principle and details of the equipment configuration and operating principles are presented and discussed. Data acquisition is via an eight channel digital electronic system and particle counts are collected on the basis of reflected light pulse time intervals which are a direct measure of particle size. Output is available as an eight point individual or cumulative size distribution or as computed averages. The practical aspects of sample point location and flow requirements for reproducible results are outlined and discussed.

Jan 1, 1990

By Dale C. Matthews

The Getchell Gold Hine is located about 40 miles northeast of Winnemucca, Nevada. Gold was discovered at the mine in 1934 and production was started in 1938 and ended in 1967 for its first phase of operation. Gold production during this period was about 800,000 ounces. In 1983, FirstHiss Gold Inc. purchased the property and initiated an exploration program that proved minable reserves of about 1,300,000 ounces of gold remained in the mine. During the exploration period, metallurgical testing was conducted to determine the most economical process that could be utilized for recovery of gold from the very refractory ore. After extensive investigation, pressure oxidation of the ore was selected, Engineering for the new plant commenced in 1987 and construction was completed in 1989 at a cost of about $87,400,000.00, not including financing cost.

Jan 1, 1990

By W. R. Reed, G. J. Joy, B. Kendall, A. Bailey

"Testing of the NIOSH-designed roof bolter canopy air curtain (CAC) has gone through many iterations demonstrating successful dust control performance under controlled conditions. J.H. Fletcher & Co. (Fletcher), an original equipment manufacturer of mining equipment, has further developed the CAC concept by incorporating it into the design of its roof bolting machines. A new CAC design has been developed incorporating the results of testing of the NIOSH design and the recent Fletcher design. Observations from smoke testing conducted on this new CAC design in a laboratory setting show promise for improved performance. INTRODUCTION Exposure to respirable coal mine dust can cause coal workers’ pneumoconiosis (CWP) otherwise known as black lung. If silica is present in the dust, the miner may develop silicosis in addition to CWP. CWP and silicosis are occupational respiratory diseases that are ultimately fatal and have no cure. The only method of prevention is through elimination of exposure to respirable coal mine dust and crystalline silica (quartz). The current occupational exposure limit (on an MRE basis) for respirable coal mine dust is 2.0 mg/m3 during each shift that a miner is exposed in the active workings of the mine or in mine facilities [30 CFR 70.100 2015]. Recently enacted legislation changes this standard beginning in August 2016 to 1.5 mg/m3 for a full working shift [Federal Register, 2014]. If the respirable coal mine dust contains more than 5% silica, the applicable respirable dust standard is reduced; calculated as 10 divided by the percent quartz present [30 CFR 70.101] so that the effective exposure limit for respirable quartz is 0.1 mg/m3 for a full working shift. Sources of exposure to respirable coal mine dust for the roof bolting occupations include infrequent maintenance and cleaning of the vacuum dust collection system and operating the bolter downwind (in the return air) of the continuous miner [Goodman and Organiscak, 2003]. Recent studies have demonstrated that vacuum dust collection systems are effective in capturing bolter-generated dust, if maintained and operated correctly and if proper face ventilation techniques are used. However, most exposure to respirable coal mine dust for the roof bolter occurs when the roof bolter machine is operated downwind of the continuous miner [Potts et al., 2011; Colinet et al., 2013]. Because of this higher exposure downwind of the continuous miner, the roof bolter is generally limited to working downwind of the miner only once during a production shift"

Jan 1, 2016

By M. Li, J. K. Thompson, A. S. Azman

"Powerful mining systems typically generate high-level noise that can damage the hearing ability of miners. Engineering noise controls are the most desirable and effective control for overexposure to noise. However, the effects of these noise controls on the actual hearing status of workers are not easily measured. A tool that can provide guidance in assigning workers to jobs based on the noise levels to which they will be exposed is highly desirable. Therefore, the Office of Mine Safety and Health Research (OMSHR) of the National Institute for Occupational Safety and Health (NIOSH) developed a useful tool to estimate the hearing loss due to occupational noise exposure in a systematic way and evaluate the effectiveness of developed engineering controls. This computer program is based on the ISO 1999 standard and can be used to estimate the loss of hearing ability caused by occupational noise exposures. In this paper, the functionalities of this software are discussed and several case studies related to mining machinery are presented to demonstrate the functionalities of this software. INTRODUCTIONPeople regularly exposed to noise can develop hearing loss at different levels of severity depending on a number of factors. The resultant hearing loss can affect one’s ability to understand speech, learning, acoustic signal perception, or appreciation of music. Hearing loss caused by overexposure to noise has long been recognized in literature. However, it still does not get serious attention by those working in noisy environments because the loss of hearing ability is a gradual process and workers are often unaware until the damage becomes an apparent problem. In the United States, occupational hearing loss is one of the most common work-related illnesses. Depending on the definition of exposure and impairment, in 2012 the National Institute for Occupational Safety and Health (NIOSH) estimated that there are between 5 and 30 million workers in the U.S. who are exposed to noise levels at work that put them at risk of hearing loss.4 In the mining industry, noise-induced hearing loss (NIHL) is particularly severe due to the fact that heavy-duty machinery is widely used to improve production efficiency, and this machinery can generate much higher-level noise than the permissible level defined by regulation. As a result, the mining sector has the highest prevalence of hazardous workplace with high noise exposures (76%) among all industrial sectors."

Jan 1, 2015

By J. O. Craig Imrie

Mine operations are being squeezed to do more with less. This is not new. But, where do mine operators turn for the next stage of improvement? Many have waged strong wars on the cost reduction front and cut back staff to the bone, yet need more improvement to remain competitive. This paper will outline an approach which a few leading operators have taken. Following the footsteps of manufacturing's view of supply chain management and basic quality management they are reaping the benefits of taking a more holistic process view of their operation. This paper presents summaries of three companies' approaches and the impact which is being felt on the bottom line.

Jan 1, 1999

By V. Arad, S. Arad

Besides the conservation and closing activities, an important issue to achieve is the environmental rehabilitation of the mining perimeters, also assuring the continuity and sustainable development of the mining activity in the Jiu Valley. Modifying and depleting the soils by mining works and dumps of mineral waste as a result of coal mining and tailing is one of the important aspects. The paper’s aim is to analyze which are minerals and resources policies of our government and to adopt measures for sustainable development in the coal mining in this region. The measures to reduce the instability risk for the mining works and waste dumps, which could affect the underground mining constructions or the related surface areas, were consider. It is most important to establish the priorities in order to obtain a high efficiency by combining the measures according to the environmental analysis and risk assessment.

Jan 1, 2005

By John A. Wolfe

Applications of mathematical statistics to the field of exploration are still relatively new. There are two primary reasons why little has been published in this field. First, if one discovers an effective technique for exploration, he does not like to disclose it. Second, the geologist needs to work closely with a mathematical statistician, and the communications barrier between the disciplines is formidable. The authors of this paper, one a geologist and the other a statistician, were interested in the economic benefit which appeared to be possible in the interdisciplinary area which they have called "geostatistics." An actual example has been selected to illustrate this benefit.

Jan 1, 1962

By A. M. Marabini, V. Alesse, Belardi. G.

An alternative flowsheet was designed for the flotation treatment of a complex sulfide ore from the Sotiel Mine in Spain. The ore contains 0.71% Cu, 2.24% Pb and 5.63% Zn. Two specially developed synthetic collectors, methyl-mercapto-benzoxazole (MMBO) and 6n-propoxy-mercapto-benzo-thiazole (PMBT), were examined. MMBO exerts a specific action on copper and zinc minerals after treatment with copper sulfate, and PMBT exerts a specific action on Pb minerals. Flotation operating variables (pH, frother type, frother quantity and feed particle size) were examined by means of rougher flotation tests to determine the optimum conditions for the new collectors. Once the optimum conditions were determined, a series of open flotation circuits were run on feeds of various particle sizes (obtained by different types of grinding). The objective was to obtain high-grade Cu and Zn concentrates. The results of the open-circuit tests demonstrated that a Cu concentrate grading from 18% to 23% Cu and a Zn concentrate grading from 40% to 48% Zn can be produced.

Jan 1, 1996

By C. Milne, T. M. Dyhr, T. E. Wilson

As time progresses, new concerns regarding long-term post-mining effects are identified, increasing mine closure costs. Regulators responding to public interest must take a “worst case” view and require post-closure monitoring or remediation processes. Although closure costs depend on the size and type of operation, general cost categories are defined, and median values (per acre, or per unit of production) are identified. Closure cost categories, as well as amounts, have increased with time. Except for increased efficiency in earth-moving and water management (surface or subsurface), there are no apparent offsets to a steady rise in closure costs. When the historical trend of closure costs is considered, it is probable that additional cost categories will come into being. For mine operators, the challenge will be to anticipate them and devise cost-effective remedies.

Jan 1, 2003

By Herbert Pöllmann

The mineralogical and chemical compositions of various waste materials undergo different reactions when treated thermally The heavy metal contents can be bound to stable phases. These minerals are called reservoir minerals. The main property of these minerals is the stability in their geochemical surrounding containing the heavy metal cations and anions. Examples for these minerals are apatites, spinels, garnets, perovskites and also water containing minerals like ettringites, metal-metal-hydroxi salts, jarosites and zeolites. When the chemical compositions of different wastes are mixed according to the compositions of the new formed minerals, a probable reuse of these wastes can be obtained. The use of waste incineration ashes for the production of cementitious binders and the use of flue gas desulfurization products for cement additives are shown. Also the transformation of highly contaminated materials into stable reservoir mineral assemblages are shown including the study of stabilization and immobilization techniques.

Jan 1, 1998

By Dale R. Ralston, Roy E. Williams, Gerry V. Winter, George L. Bloomsburg

GENERAL STATEMENT The primary objectives of any field data gath¬ering effort should be to (1) identify and gather the data necessary for the project and (2) obtain the data in a state-of-the-art manner. All too often the initial field data are collected both areally and tem¬porally in an illogical manner without the guidance of a conceptual model of the ground water flow systems involved or even a review of existing geo¬logic literature on the area of interest. The initial data collected frequently are of limited value while necessary basic reconnaissance information is miss¬ing. Initial field data should be collected with the intent of developing a hydrologic overview of the potential mine site and surrounding area. Ob¬viously, one of the initial objectives is to define the area requiring a hydrologic investigation. The data requirements should be identified by the time frame in which collection should be made and by the corresponding increase in sophistication of the data requirements with development and operation of the mine. The data requirements are summarized in Table 1. INITIAL LEVEL SITE INVESTIGATION Area Determination The initial task of any hydrogeologic investi¬gation is to determine the boundaries of the area requiring study. Obviously, the site of the proposed mine is included in the study area. The areal extent beyond the site may be determined from an eval¬uation of existing geologic and topographic maps. Those formations that overlie the ore body, the formations containing the ore body, and the formation(s) that lies immediately beneath the ore body are of direct concern for proper site recon¬naissance. Additional formations below the ore body may require study depending upon their thick¬ness, hydraulic conductivity, and degree of inter¬connection with the mine workings. This initial viewpoint identifies hydrostratigraphic units based strictly on geologic concepts such as mineralogy and structure. Formation outcrops, synclines, an¬ticlines, faults, and fracture and joint patterns are used to delineate the area of the site reconnaissance. The simplistic hydrogeologic environment (il¬lustrated in Fig. 3, chapter 2) requires that field data be collected via test wells and/or geophysical techniques. This approach is necessitated by the lack of surface features such as formation outcrops, streams, and springs. Fig. 5 (chapter 2) illustrates a slightly more complex hydrogeologic regime. The potential mine sites at locations A, B, C, D, and E each intercept a different ground water flow sys¬tem or combination of flow systems. Therefore, each mine location requires that a different area and size of area be investigated. A more complex geologic setting as illustrated in Figs. 6 and 7 (chapter 2) may be approached differently. The area included for the site recon¬naissance should encompass sufficient surrounding area to include the outcrops of those formations suspected of being influenced by the future mine. Even adjacent areas not suspected of being influ¬enced may be investigated if the formations of in¬terest crop out in those areas. Such an extension of the area of investigation would provide a greater regional understanding of the hydrogeologic properties of the formations (hydrostratigraphic units) of interest. Geologic Investigation The initial step before conducting the site re¬connaissance is to review all existing literature on the geology of the area. Existing information should be augmented with new exploration data on the dip, strike, thickness, and lateral extent of the for¬mations in the area. Exploration hole logs should be reviewed for indications of lost circulation, rub¬ble zones, and water producing zones. Existing aer¬ial photos such as those available from the US Department of the Interior, EROS Data Center,

Jan 1, 1986

By H. Haas

European coal mines are facing a very difficult situation. Despite a steadily increasing world energy consumption, the sales of European coal mines have been going down and production has to be adapted. The reason is the collapse of energy prices aided by the decreasing rate of U.S. $ to Deutschmark in the last few years. The problems are not due to the development of European mines themselves. Assured energy supplies are an important condition for the health of a nation&apos;s economy. Contribution of domestic energy production ensures some degree of independence from world market fluctuations as to supply volumes and price, and maintaining jobs and should be achieved within the framework of economic constellations. Governmental energy programs are planned towards meeting this end.

Jan 1, 1989