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By Haydn H. Murray

Since the advent of machine coated paper in the mid 1930's, the kaolin industry has had a remarkable growth, In 1935 the domestic production of kaolin was 500, 000 tons and in 1970 the estimated production was in excess of 3. 5 million tons. The process industries which use kaolin most extensively are paper, rubber, paint, ceramics, plastics, catalyst manufacturers, ink, and pharmaceutical. The paper industry is by far the largest consumer of kaolin using approximately 70 per cent of the total tonnage mined and beneficiated. Up until 1970 the major kaolin producers were able to expand rapidly enough to supply the demand but for the first time in thirty years the demand is expected to be in excess of mining and beneficiation capacity through at least 1975. The major reason for this is the expansion of coated paper production in Europe and Japan. Two areas supply the lion's share of kaolin for the world markets. These are the Cornwall area in extreme southwestern England and a limited area of Georgia and South Carolina in the southeastern U. S. The English kaolins are primary - (found in decomposed granite) whereas the Georgia-South Carolina kaolins are secondary - (found in lenticular, continuous beds in the Tuscaloosa formation of Cretaceous age. ) The English kaolins are mined by hydraulic methods whereas the Georgia-South Carolina kaolins are mined by dragline or shovel and benefidated by using a wet process for the majority of the production and/or a dry

Jan 1, 1971

By James G. Tilton

Subsidence resulting from mining operations, has been the object of sporadic study for many years. Reports have shown that subsidence has ranged from minor settlement detected only by precise measurements to great slips where buildings are destroyed, roads disrupted, and large fissures opened at the surface. For years, a controversy has raged over the question of whether there is a positive or negative angle-of-draw. None of these questions can be given a flat answer for the variables controlling, subsidence are infinite. Generalizations can be made for various situations and areas but some means of control must be executed.

Jan 1, 1966

By Martin Langenderfer, Catherine Johnson, Alexander Douglas

Mine haul roads degrade rapidly due to extreme loads on suboptimal construction materials. Unmanned aerial vehicles (UAV) are suited to quantify large-area road-network conditions, such as surface roughness, defects and grade to optimize remediation of poor conditions and reduce overall costs. Mine haul roads present unique challenges, such as material type and edge characteristics, to automatic road detection that often fails, requiring manual road input. This research work proposes a new method using the road center determined by the principal curve of a haul truck’s path. Analysis grids were created from this center line. A dense point cloud from UAV photogrammetry was generated and multiple linear regression analysis was conducted on each individual grid. The root-mean-square error in each grid indicates the surface roughness, and the change of slope between grids indicates the road grade inconsistencies. This method was applied to 26 road sections, and the results were validated by images taken from the truck operator’s vantage point. Critical defects were identified including excessive pothole formation, corrugation, depressions retaining water, and narrowing of travel lane. The results demonstrate this is a valid method of road identification and quantification of road defects at a mine site.

Apr 1, 2024

The primary goal of a maintenance information system should be to aid the maintenance department in providing the required equipment or plant availability at the lowest possible cost. To achieve this goal, the system must provide information in support of the following objectives: (1) establishing the best fleet, equipment, and component configuration; (2) establishing the best maintenance program; (3) executing the defined maintenance program efficiently; and (4) monitoring equipment availability. These objectives can be satisfied with five groups of reports. Each of these groups should provide regular, periodic reports to aid in planning and monitoring trends, exception reports to identify problems, and on-request reports to provide analytical capabilities.

Jan 1, 1979

By Robert H. Robinson, Levent Ozdemir, Russell J. Miller

The paper summarizes an investigation into the applicability of mechanical excavation to oil shale mining; identifies available machine types that are best suited to various aspects of the mining operation; presents preliminary comments on the configuration of an "IDEAL" oil shale mining machine; and establishes the background information necessary for conceptualizing and evaluating new mining methods using mechanical excavation equipment. Conclusions are also presented as to the best currently available systems, as well as potential future systems.

Jan 1, 1983

By K. Luxbacher, D. T. Hristopulos, S. Schafrik, J. Diaz, Z. Agioutantis

Big data is generated from both surface and underground mining operations. Such data contain a wealth of information concerning safety and health in the workplace and production parameters. This paper will discuss the progress towards developing an accurate forecasting model for methane gas concentration based on the analysis of data collected from Atmospheric Monitoring Systems in underground coal mines employing time series models. Several procedures need to be applied to raw data, such as data cleaning and filtering for outlier removal, data homogenization and segmentation, and exploratory statistical analysis. The data analyzed were retrieved from two coal operations in the Eastern US. A negative correlation between barometric pressure and methane gas concentration was established, at least for certain data segments. Such correlations raise the possibility that barometric pressure data can predict variations of gas concentration in the mine. The datasets will be further investigated to establish the robustness of barometric pressure and gas concentration correlation and explore the dependence of gas concentration on other factors related to mine design and operations

Mar 2, 2022

By Franziska Wolf, Rainer Ellmies, Helmut Mischo

"Mining is an important part of the economy of Namibia. In 2016, 11.1 percent of the GDP was the result of mining activities with 22 active mines (The Chamber of Mines of Namibia, 2016). Only one of them consists of an underground mining operation.The global annual production of fluorspar is approximately 5.4 to 6.3 Mt (6 to 7 million st) (U.S. Geological Survey National Minerals Information Center, 2017). Okorusu has produced on average about 45 kt/a (50,000 stpy) in recent years (U.S. Geological Survey National Minerals Information Center, 2015).The Okorusu Mine is Namibia’s only fluorspar mine. Fluorspar was mined in an openpit mine with four individual pits (A-D) since 1980. In 2014, the mine closed due to the increased stripping ratio and beneficiation problems. The mine assets were bought by Gecko Namibia. Currently, Gecko uses parts of the processing plant for beneficiation of graphite from a neighboring mine. Figure 1 shows a panoramic view with the four pits and the mine village.The intent is to develop a concept for the further underground development of the mine. There are still about 6.3 Mt (7 million st) of measured resources left in the deposit, with an average grade of 27.5 percent CaF2. This study focuses on the underground mine design. The above-ground plant and facilities are considered as remaining unchanged.For solving the task to design the mine, a site visit for data collecting was conducted. Resource estimations were calculated based on existing drill data, and consequently, block models were created. The development of the mine design included the selection of the most suitable mining method, mining technology and mine organization. Moreover, some economic considerations are pointed out, followed by a profitability assessment."

Jan 2, 2018

By LUIS ALBERTO TORRES-CRUZ

The Plewes method is relatively well known among geotechnical engineers interested in assessing the liquefaction potential of soil deposits. Furthermore, it was one of the four methods considered in the post-failure investigation report of the Feijao Dam I, also known as the Brumadinho Dam, in Brazil. The inclusion of the method in that report is likely to increase its visibility among geotechnical practitioners tasked with assessing the liquefaction potential of tailings. While the authors of the method duly presented it as a screening method, more recent technical literature contains conflicting views on its reliability. Considering the popularity of the method and that the safety record of tailings dams is a cause of great concern, this study assessed the uncertainty of results from the Plewes method. The study concludes that, even under optimistic assumptions, the results of the method are too uncertain for detailed characterization of tailings deposits.

By George L. Atwood

The Monsanto Company's Henry Mine is located 17 miles northeast of Soda Springs, in the southeast corner of Idaho. Ore being mined is phosphate rock which lies in the Permian Phosphoria formation. The ore is the raw material for Monsanto's three furnace elemental "P" plant near Soda Springs. The finished product from the furnaces is elemental phosphorus which is subsequently used in the manufacture of detergents, food preservatives, fire retardants and other consumer items. Mining is by open pit methods using 0-9 crawler tractors to rip and push-load rubber tired scrapers in stripping and mining operations. The equipment spread consists of six D-9G crawler tractors, four Caterpillar 6578 scrapers, eight Euclid S-24 scrapers, one Reich T750 drill and one Caterpillar No. 16 patrol plus various support equipment. Stripping is performed on a 12-month basis, two shifts per day. Mining is performed mainly in the summer months on a one shift basis. The hauling season begins May 15 and ends November 1 due to freezing weather and snow conditions. Annual production is 1,000,000 tons of phosphate rock and 2,500,000 to 3,000,000 yards of stripping. Stripping, mining and hauling is performed for Monsanto by Dravo-Soda Springs, a mining contractor. Dravo-Soda Springs owns, operates and maintains all equipment used in stripping, mining and hauling. The contractor is paid for stripping by the bank yard and for ore mined and hauled on a tonnage basis. The Monsanto elemental phosphorus plant began production in 1952 with ore being trucked to the plant from the Ballard Mine. Haulage was over public roads in 15, 24-ton semitrucks. A private haul road was constructed from the Ballard Mine to the Monsanto Plant in 1958 and 1959 to accommodate trucks with two twenty-yard trailers. This 11/ mile road was first used in the 1959 hauling season. In 1965, five new Kenworth tractors with two, 'forty yard trailers were introduced into the haulage system. These units carried 120 ton payloads and were used until

Jan 1, 1972

By Leonidio Stegmiller

Since the petroleum crisis in 1973, charcoal1 is being considered one of the most important fuel for the Brazilian consumers, mainly for pellet's producers. In replacing fuel by charcoal mixed up with ore, obviously one of the first thing to be investigated is its influence in the product's quality. Special attention has been given to the metallurgical characteristics. This paper infocus the effect of increasing dosings of charcoal to the pellet's porosity and how other physical and metallurgical characteristics will be affected accordingly. This work was carried out using two different finesses of charcoal and dosing varied from 0.5 to 2.0%.

Jan 1, 1982

By M. M. Fine

One of the most persistent topics at technical gatherings and in the recent scientific press has been the reduction of iron ore. To cite some of them, in May 1960, a symposium on the subject was sponsored by the Electrochemical Society. The proceedings, comprising two dozen papers, were later published.3/ More recently, November 1966, a similar gathering took place at Michigan Technological University, Houghton, Mich. The latest meeting was the International Congress on Production and Utilization of Reduced Materials, Evian, France, May 1967. If the volume of literature, symposia and conferences is a measure of industry concern, then current interest must be at a high level. To the casual observer of the metallurgical scene, the abiding and recurring attention to iron ore reduction outside the blast furnace must be somewhat puzzling in that so much research endeavor has resulted in so little commercial activity.

Jan 1, 1968

By P. James

"INTRODUCTION Control of target stream acidity is widely used in MIW (mining influenced water). Tailoring pH (a measure of acidity) finds application for controlling key chemistry in both process and waste streams. Traditional lime addition for neutralization and precipitation is most often used but has high reagent costs and results in large amounts of mixed metal sludge requiring costly disposal. A new adaptation of BPS’s patented DEMET™ technology (Dynamic Electrolytic Metal Effluent Treatment) platform offers a potentially improved and “reagentless” alternative to traditional chemical addition for pH adjustment. Electricity rather than chemical addition utilized in BPS’s proprietary approach controllably tailors target stream pH. The method offers a simple, low-cost processing technique yielding cleaner treatment chemistry. BPS’s “green” approach may yield lower operating (OPEX) and life cycle costs and significant reductions (up to 50%) in sludge generation compared to conventional lime treatment. It can also allow new opportunities to generate revenue via selective recovery of valuable processing byproducts. Specific savings and revenues depend on the target site chemistries, details, and processing goals. A more detailed discussion of the process and its operational principles may be found in Reference One.[1] Here application of the BPS treatment to POx (Pressure Oxidation) leaching as an alternative to traditional chemical addition is examined. An example operation process flow for gold mining is considered.[2] Promising processing points for potentially replacing conventional processes with DEMET are noted. The possibilities for lowering OPEX costs, lessening sludge creation, and capturing various valuable byproducts and residuals are examined. Financial life cycle benefit estimates of the principal gains provided by DEMET application to the example operation are noted. Extension and generalization of the analyses to a wider range of scenarios is explored."

Jan 1, 2016

By Malte J. M Gurgel

Subsurface spatial planning is becoming increasingly important in view of competing underground applications. This development is influenced by global agreements to reduce greenhouse gas emissions. Therefore, precise knowledge of the underground space is a basic prerequisite for future applications. The three-dimensional registration and reliable georeferencing of underground infrastructures can establish a holistic geodata basis for such tasks. Those tasks are discussed both for the development of energy projects such as deep geothermal energy as well as for storage applications. Research on geothermal energy has been carried out at RWTH Aachen University as part of the SuperC project in a license field in the Aachen area since 2001. Recently, this research has been extended to include monitoring aspects in the overlapping GEObservatorium Aachen field. The documentation and visualization of underground activities using photogrammetric methods like Structure from Motion is discussed based on recent research in sites for the final disposal of radioactive waste. Finally, both applications provide an outlook on supporting underground projects by using high-resolution geodata.

Feb 1, 2025

By D. W. Park

Longwall mining is considered the most efficient underground coal mining technique in terms of coal extraction ratio, production rate, and safety standards. Due to the increasing demand for higher coal production, wider panel and faster face movement have become the recent trends. Thus, longwall mining can create unexpected threats such as roof falls, excessive face convergence, shield damage and numerous maintenance problems causing sudden interruption of coal production and serious safety hazards. A recent study at the University of Alabama is dedicated to develop LoSCoMS (Longwall Strata Control and Maintenance System) which integrates real-time shield monitoring, data presentation, analysis, forecasting, and warning modules. The main objectives of this system is to provide the stability and maintenance information, at every minute, such as high load, low setting pressure, leg leakage, etc., analysis of various mining and geological parameters to determine past and present roof characteristics and forecasting of loading patterns for the following mining cycles, next periodic weighting, etc. Using this unique system, mine operating personnel are well aware of past, present and future roof loading patterns at the longwall face, and thus, proper safety measures can be taken ahead of time.

Jan 1, 1997

Longwall mining has existed in Utah for more than half a century. Much of this mining occurred at depths of cover that significantly exceed those encountered by most other U.S. longwall operations. Deep cover causes high ground stress, which can combine with geology to create a coal burst hazard. Nearly every longwall mine operating within the Utah’s Book Cliffs coalfield has been affected by coal bursts.

Jan 7, 2020

By C. McKinnon

Climate change is the central challenge facing the mining industry, wherein producers must simultaneously ramp up production to provide the raw materials for clean technologies while transitioning to carbon neutrality. While transitioning to renewables will take time, mines can start improving energy efficiency while improving productivity today. This paper proposes a novel technology ecosystem that can help. By monitoring mine shovels, loaders, haul truck paths, and conveyor belts, the proposed technology enables particle size measurements throughout the operation, truck and belt volume monitoring, ground engaging tools monitoring, and boulder detection.

Mar 2, 2022

By T. Gupta, T. Ghosh

"In recent years, the demand for Rare Earth Elements (REE) have grown rapidly due to increasing demand and global supply shortage. The supply deficit of these critical elements has encouraged the search for new sources of REEs, possibly Coal and Coal byproducts. Coals from certain parts of the world can be rich in REEs, and can approach a total concentration of 1000 ppm. Two Alaskan coal samples were investigated for the effect of size and density on the concentration of REEs on three selected size fractions. Flotation tests were conducted for finer fractions. Additionally Bottom ash and Fly Ash samples from a power plant have been examined for REE concentration. The results show that the upgrade potential for REEs on ash basis from whole coal basis ranges from 2:1 to 4:1 for Wishbone Hill and Healy coal samples respectively. Flotation of the finer fraction for both coal samples, conducted under similar conditions, reveal higher concentration of REE’s in the tailings. Both coal samples have a comparatively higher LREE content than HREE. Trends of REE content of the power plant products on ash basis revealed that Fly Ash has a slightly higher concentration of both LREE and HREE than Bottom Ash. Keywords: Rare Earth Elements, Coal, Coal Ash INTRODUCTION Rare Earth Elements (REEs) and their compounds are vital components in industrial, automotive, petrochemical, defense and medical applications. Dysprosium in combination with other elements is used in laser materials and nuclear control applications. Neodymium is present in magnets that are used in green power generation such as the manufacture of wind turbines and also in hybrid cars. Europium, Terbium and Yttrium are used for devices that have visual displays such as computer screens and laptops [1, 2]. REEs pose fewer environmental problems of disposal and recycling than conventional heavy metal counterparts [1]. Rare-earth metals are key ingredients for radar systems, avionics, modern national defense and satellites [2-8]. In the last 25 years China has been mining, processing and refining Rare Earth elements at affordable prices thus gaining a virtual monopoly in the market. The many fold rise of the prices of REE elements over the last few years and frequent disruptions in supply has forced various nations to invest in indigenous extraction of REEs by increasing production from previously productive sites and to expand the production from new alternate sources including coal and coal byproducts [9]. Coal and Coal beds have been found to be significantly enriched with certain critical metals and can be a potential source for both Light Rare Earth Elements (LREE) and Heavy Rare Earth Elements (HREE) [10]. Moreover, coals with high REE concentrations have been discovered in Pavlovka and Rakovka coal deposits in Russia, Appalachian deposits in USA, Sichuan Basin deposits in China and others across the globe [10-13]. A recent study from China looked at how different trace elements (including numerous REEs) partition in various size fractions of Antaibao coal from China. The finding indicates that the REEs, phosphorous, and thorium all have their high concentrations in the particle sizes 0.5 to 3 mm, and 6 to 25 mm. REEs are also often present in the form of phosphates such as monazite in coal [13, 14]. The objective of the study is to identify the concentration of REEs in Alaskan coals and to investigate the effect of density and size in the distribution of REEs in coal and coal byproducts."

Jan 1, 2016

By Ch. Apostolaki

Eighty samples from Roman wall paintings from ancient Corinth were studied by means of optical and scanning electron microscopy coupled to an energy dispersive analyzer, X-ray diffraction and image analysis techniques. The goals of the study were the identification of the exact nature of the pigments and the technical features of paint application (binding medium, adherence to plaster, thickness of the pigment layer), which would provide evidence about the painting technique (fresco or secco). The main plaster is calcitic with secondary calcite as a cement binder to the primary calcite grains. All pigments, except Egyptian Blue, were naturally occurring ochres or pigment minerals, such as limonite, goethite, hematite for yellow, brown and red hues, cinnabar for red hues and celadonite for green color. The presence of specific elements such as Ni and Cr or minerals such as olivine, in the yellow, brown and red pigments, gave an indication about the provenance of the original pigments, which seems to be from Cyprus. The black color was represented using charcoal. It seems, finally, that for the pigment application the fresco technique was used, while secco is also apparent.

Jan 1, 2006

By Bernard P, Lhoumaud E, Gunzburger Y, Conin M, De Santis F, Kinscher J

Seismic repeaters are commonly observed in natural fault zones dominated by slow aseismic motion. The corresponding seismic signal, characterized by highly similar wave forms, is usually interpreted as the repeating ruptures of locked asperities on fault planes (“patches of higher roughness”), loaded by a-seismically slipping areas (“creeping areas”) (Chen & Lapusta 2009; Bourouis & Bernard 2007). Only very few occurrences of seismic repeaters have been reported in underground mines, where these phenomena are rather unexpected since the stress state and the seismic wave propagation continuously evolve with the advancing excavation front (Kinscher et al., 2020). A recent study based on a local seismic network installed in the underground mine of Garpenberg, Sweden, has shown that seismic repeaters and multiplets represent the main part of the total released seismic energy (magnitude of seismic events: -2 < M <1, on moment magnitude scale), with some seismic families being active during several months to years. It is suggested that repeaters are linked to aseismic slip on pre-existing talc-filled fractures, induced by the excavation, and loading of asperities. These results imply that part of redistribution of stresses in the mine is due to aseismic slip, which might explain the observed distant and delayed seismicity.

Apr 26, 2022

By William E. Spence

Gold was discovered at the Haile mine in Lancaster County, South Carolina in 1827 or 1828, and since that time the mine has been worked intermittently by both open pit and underground methods until its forced closure in 1942 by World War II. Production figures are incomplete, especially for the early years, but the total gold produced is estimated to have been greater than 200,000 ounces. Thus, the Haile mine has been the most productive gold mine in the eastern United States. The upper, residually enriched ores were relatively rich, but the bulk of the production has come from the mining of lower grade ores.

Jan 1, 1978