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By John C. Brower

The purpose of this paper is to examine the Gays in which- the policies of the U.S. government, mining companies and third world countries affect each other with regard to the availability of minerals. The interaction involves U.S. policy towards the mining industry, the policies of the companies themselves, and the policies of third world countries towards the U.S. and multinational companies. It is assumed in this discussion that U.S. policy will continue to be to seek certain minerals from abroad rather than attempt to develop domestic sources for all its requirements. This would seem to make sense both from the standpoint of cost, and for preserving what domestic resources there are so as to maintain some degree of market leverage. In today's jargon, this means greater dependency on the "third world", which, for this discussion, includes virtually all the nations in Africa, South America and Asia. Concern for availability raises the important distinction between dependency and vulnerability, and as the Director of the Bureau of Mines has pointed out, the two are not the same. Dependency is not neccessarily a bad thing; it is vulnerability that counts (Norman, 1980)

Jan 1, 1982

The 2012 North American Tunneling (NAT) conference is expected to attract more than 800 tunneling and underground construction professionals. But don?t let the North American part of the meeting?s title fool you. Many of the attendees will come from all over the world. The meeting is scheduled for June 24-27 at the JW Marriott Indianapolis Hotel in Indianapolis, IN. In addition to two and a half days of technical programming, the accompanying exhibit has attracted 116 exhibitors in 140 booths. And the conference will include short courses, a field trip and plenty of social activities that will give attendees the opportunity to catch up with each other.

Jan 1, 2012

By J. R. Hoskins

Method - A direct approach to instrument users, initially by letter and later by telephone or personal contact was made. The resultant data was compiled to give specific use information on the seven instruments. During the course of the study attempts to evaluate the Griswold Gage were abandoned when it became apparent that the gage was not being commercially produced. One company is developing the gage for its own use. The information presented is the result of over 1200 inquiries.

Jan 1, 1973

By James M. Link

The first rule of mineral deposits always seems to be: the deposit is never close to the market. With gems and precious metals, this is not much of a problem. But with most of the mineral commodities used in today's world, transportation becomes a major part of the cost to the consumer. In Japan, for example, more than 60% of the cost of coal to the consumer may be attributed to transportation. The purpose of this article is to examine pipeline transportation, particularly mineral slurry pipelines, as a means of getting the mineral to market. Pipelines Today Regulated pipelines in the US totaled nearly 724 Mm (450,000 miles) in 1980 according to the Federal Energy Regulatory Commission (FERC). Worldwide, more than 210 Mm (125,000 miles) of new pipelines will start construction in 1982 at an estimated cost of more than $150 billion. According to the Bechtel Corp., the period between 1982 and 2000 will see major growth in pipelines of all kinds. In North America, major movements of crude oil from Alaska and synfuels from the Rocky Mountains will require the construction of nearly 16 Mm (10,000 miles) of new pipelines. Nearly 42 Mm (26,000 miles) of new gas transmission pipelines will be needed to tap both US and Canadian arctic gas fields and move the gas to major markets on both coasts. Other pipelines will be required to move additional quantities of natural gas from the Rocky Mountains to more populous regions. Bechtel says more than 24 Mm (15,000 miles) of slurry pipelines will be needed to transport coal from both eastern and western coal provinces to the Mississippi valley and coastal areas. In 1980, 125 companies delivered more than 1 km3 (6.5 billion bbl) of crude oil and 652 hm3 (4.1 billion bl) of products in the US. At the same time natural gas pipelines transported 498 km3 (17.6 trillion cu ft). The reported investment by these companies was nearly $20 billion at the end of 1980. Advantages of Pipeline Transportation The obvious success and vitality of the oil and gas pipeline industry is based, at least in part, on the fact that pipelines are a very efficient and low-cost method of transportation. This fact, coupled with the need for lower cost trans¬portation, has led to the marriage of oil and gas transmission technology and the bulk mineral solids transportation industry. The off-spring of this marriage is the mineral slurry pipeline. Slurry pipelines have a number of advantages over other transportation methods. One of these is the fact that they are buried-out-of-sight, out-of-mind. Second, they are relatively small users of labor because they lend themselves to automation and remote, or even computer control. Third, they offer an attractive economic alternative to other transportation systems. For example, for a 1000 km (621 miles) distance, rail costs of 1?/ km (1.7?/ton-mile) are about equivalent to slurry pipeline costs. But, as the distance increases, pipeline cost per t-km continues to drop while equivalent rail charges remain essentially insensitive to distance. Where existing rail, barge, or ocean ships are available, the cost of new construction associated with a slurry pipeline probably will render it noncompetitive. However, where new rail or other construction is needed, the cost of a slurry pipeline is very competitive. About three-fourths of the cost of a pipeline is in pipe, fittings, and construction. Nearly a fifth of the investment is in pump stations and the remainder is in right-of-way, surface facilities, utility acquisition, communication facilities, and other support areas. The fact that pipelines are capital intensive is, at the present time, a mixed blessing. For example, the delivered cost of coal in a hypothetical project doubles when the cost of money rises from 9% to 17.5% per year. The largest cost element for delivered coal in this example is in depreciation and finance charges. The next largest cost element is electricity to power the pumps, with labor making up the smallest increment of the delivered cost of coal. World Slurry Pipelines The idea of a slurry pipeline was probably first investigated in the latter 19th century, but the first ones were successfully built and operated in the US in the early 1900s. Today, they are fairly common worldwide. Table 1 shows a number of the world's slurry pipelines. An examination of these will further emphasize the fact that pipelines provide a cost competitive alternative where new construction of a transportation system is required. In each of the examples, the desired mineral commodity is located in a remote corner of the world, markets are at a great distance, value of the commodity is not great, and no other transport system is available.

Jan 10, 1982

By David V. Fitterman, David L. Campbell

We've used direct current resistivity (DC), electromagnetic (EM), induced polarization (IP), and ground-penetrating radar (GPR) geoelectrical methods to study mine dumps. The results reflect lithology, pore water saturation, and dissolved solids in the pore water. If the pore water has a pH less than 5, conductivity maps can indicate acid generating potential. IP measurements can help distinguish mineralogy in mine dumps, especially concentrations of sulfide minerals. EM and DC can help locate acidic/high TDS groundwater associated with mine dumps. GPR methods failed at the sites we studied in the West. Our own conclusions are augmented by those from the recent literature.

Jan 1, 2000

By Guy Bridges, Elton Ko, Cheng Ting Ning, Owen Ng, Giovanni Chang, Robert Anderson

"PROJECT OVERVIEWThe Liantang/Heung Yuen Wai Boundary Control Point (BCP) and Associated Works will be the seventhland crossing between Shenzhen and the Hong Kong Special Administrative Region (HKSAR) of China.The project includes site formation of about 23 hectares of land for the development of the BCP and anapproximately 11-kilometre (km) long dual two-lane trunk road (the “Connecting Road”), connecting theBCP with the existing Fanling Highway. The route alignment is within a relatively rural area of HongKong, with very limited similar infrastructure works carried out nearby. It passes beneath bothmountainous terrain, and alluvial plains, and falls within an area of several major regional faults andassociated metamorphism, resulting in a complex variety of ground conditions.ALIGNMENTThe Civil Engineering and Development Department of the Government of the Hong Kong SpecialAdministrative Region carried out extensive public engagement in selecting the alignment of theConnecting Road. Over 70 consultation forums with public bodies, including the District Councils, RuralCommittees, local representatives, etc. were held during the alignment design process. In order toalleviate the concerns of various nearby villages, and to minimize land clearance and environmentalproblems, the original alignment of 10 km long (3.5 km of tunnels and 6.5 km of viaducts) was revised toits final alignment of 11 km long which comprises 5.7 km of tunnels, 4.3 km of viaducts and 1.0 km of atgrade roads.The finally adopted alignment commences at the southern end with an interchange with the existingFanling Highway, part of Route 9, which is a dual three lane expressway currently being widened to dual4 lane. Alongside the expressway is the main rail connection to the mainland of China, and theinterchange viaducts connecting to the southern portal of the Lung Shan tunnel must cross over thisrailway. The southern portal is located in the foothills of Lung Shan, and the 4.8km long tunnel is alignedin a north-northeasterly direction. The southern half passes under mountainous terrain of Lung Shan,and then crosses a valley containing the Kwan Tei river. The northern section comprises low hillsseparated by an alluvial plain and Tan Chuk Hang village area. At the northern end, the tunnel turns tothe north-west to connect with Sha Tau Kok road, an existing single carriageway road, with a newroundabout interchange. Mid-way along this tunnel there will be a ventilation building, connected to the main tunnel by a 330m long ventilation adit. To the north-western side of this interchange is the900m long Cheung Shan tunnel, and after this the remaining 4.3km of the highway connecting with theBoundary Control Point is to be constructed as an elevated viaduct. The alignment is shown in Figure 1."

Jan 1, 2016

By Yu. A. Polozov, V. A. Lagunov, O. Yu. Lushinkova, Yu. I. Svirskiy, Eh. Ya. Kipko, Roy A. Williams

The effectiveness of the grouting of saturated, fractured rock in the vicinity of underground workings depends to a great extent on the correct interpretation of the specific hydrogeological conditions at the site. During the planning of grouting operations, calculations of the hydrogeologic co-efficients and of the parameters of the isolating grout curtain(s) and the procedures for forming the curtain(s) must be based on valid hydrogeologic characteristics of the fracture system of the rock within each hydrostratigraphic unit (Anon., 1976). This chapter presents a discussion of the background information that must be collected for these purposes. Details of testing are presented in Chapter 3. The general design of new or the reconstruction of existing underground workings requires a broadly based organization having the expertise to develop a grouting operations plan once it acquires the necessary information. The needed information includes: 1) general information about the hydrogeologic section, 2) the engineering design of the underground workings, 3) the geology of the region, 4) the hydrochemistry of the ground water, 5) the hydraulic properties of the rock, 6) the characterization of all gases present, and 7) characterization of the rock's physical-mechanical properties which is necessary to avoid or control hydrofracturing . The geological documentation portion of the hydrogeological investigation is prepared based on the results of geologic mapping, geophysical surveys and on geo-exploratory operations at a regional and local scale. Geological data from the excavation of other underground workings in adjacent areas of the region is also included. Finally the results of site specific investigations in boreholes constructed at the site of the proposed underground activity are incorporated. A section of the preliminary report entitled "General Information about the Project Site" patterned after the parent STG guidance document on this subject must be com- piled based on the contents of geological reports and on the general construction plan for a new project or the plan for reconstruction of an existing operation. This section of the preliminary report must contain concise information about the conditions under which the planned grouting operations are to be conducted. The information must cover the geo- graphic, administrative, and economic subject areas also. Information about sources of electrical power, heat and water supplies, the presence and characteristics of local construction materials suitable for making grout (particularly clay and cement for the clay-based grout), transportation, and the status of communication lines and other services must be included in this section. Map scales for this section should be on the order of 1:25,000. The technical characterization of planned underground workings is presented in a project report chapter called "General Construction Plan for a New or the Restoration of an Old Operation. " The characterization comprises concise information about the purpose of the workings, the planned depths (for shafts) and the length (for horizontal and inclined workings), the inside and excavated diameters (for shafts), the cross-sectional area (for inclined and horizontal workings), and the face and mouth markers. If excavated underground workings exist in the region, then a concise description of them must be provided. The characterization of all excavations and all operational conditions must be specified. The location within the general structure of the proposed operation is specified. Flow charts must be included in this section that show: 1) the plan for opening the deposit, 2) the plans of the mining operations, and 3) the planned geological sections as they relate to the main workings. These graphical flow charts and appendices are drawn in scales of 1:2000 or 1:5000. 2.1 GEOLOGICAL CHARACTERIZATION The geological characterization of a site of proposed underground workings includes the following principal subject areas: stratigraphy, lithology, structural geology and a characterization of the status of fracturing. 2.1.1 STRATIGRAPHY AND LITHOLOGY A description of the geological section of the rocks to be intersected by the planned underground workings is complied on the basis of: 1) research data derived from core extracted from exploratory boreholes and monitoring boreholes, 2) the documentation and mapping of all natural out- crops in the region, 3) the data from all existing under-ground workings in the regions where operations are being canied out already, along with data from adjacent regions, 4) the data from surface and borehole geophysical investigations (standard and specially developed logging methods, and 5) regional stratigraphy. The geological description of the rock must express the maximum detail possible. The description provides the name of the rock, the granulometric composition (for fragmented rock), the composition and type of stratification, the drilling characteristics of the rock, a visual estimate of porosity and density for each stratum identified, the karstic

Jan 1, 1993

By Amila Sandaruwan Ratnayake, T. Dilmi. U. Wijewardhana, H. C. S. Subasinghe

The value addition potential of ilmenite was examined using several characterization techniques. Raw ilmenite is composed of 93.65 wt.% of FeOTiO2, 3.55 wt.% of SiO2, 1.22 wt.% of Al2O3, and the remainder being other minor oxides. Ilmenite and powdered carbonized coconut shells were mixed in the weight ratio of 4:1. A separate fraction of the same mixture was added with powdered seashells in the weight ratio of 4:1:0.5. Six fractions of each mixture were distinctly milled from 1 to 6 h in a planetary ball mill. XRD spectra (broadened and diminished reflections of ilmenite) and FTIR observations (Ti―O―Cbonding) of milled samples indicate the possible incorporation of carbon into the ilmenite structure. Any clues of an occurrence of new rutile peaks were not observed in XRD spectra of milled samples. Consequently, the carbothermic reduction has not been initiated during mechanical activation. In this case, samples powdered for 6 h in a mill were isothermally annealed for 2 h under normal airflow at temperatures of 800 °C, 1000 °C, and 1200 °C, respectively. According to the X-ray diffractograms, the annealing temperatures of 1000 °C and 1200 °C exhibited almost similar trends with rutile (R), pseudobrookite (PB) and elemental iron (F), and a very few ilmenite (I) peaks. Consequently, 6 h of milling and 1000 °C annealing were concluded as the optimum conditions for the carbothermic reduction. Moreover, this study indicated seashells as a potential rate raiser for the carbothermic reduction of ilmenite at 800 °C. Therefore, this process is applicable to upgrade ilmenite into a mixture of synthetic rutile and elemental iron.

Mar 29, 2021

By Turan Uysal, Ramazan Aydogmus, MURAT ERDEMOGLU

The paper investigates the effects of calcination for thermal activation and intensive milling for mechanical activation on aluminum recovery by acid leaching of pyrophyllite ore enriched via attrition scrubbing and froth flotation. The study compares these methods in terms of energy consumption and aluminum recovery, concluding that mechanical activation is more economical and environmentally friendly.

Nov 1, 2023

By Harrison R. Cooper

Approximately 40 concentrators throughout the world have successfully adopted computer control for flotation circuit operation since 1969. Successful use of flotation control, gaining up to 2% efficiencies, has largely derived from effective employment of on-stream slurry analyzers and integration of key measurement data through digital processors. Requirements for reliable measurement have also led to improved functional reliability in magnetic flow meters, pH, reagent feed, and other key elements. Methods used in computer control of flotation will be reviewed and variations in operating philosophies will be described with reference to the approaches taken to flotation automation.

Jan 1, 1979

By J. C. Wynn

J.R. Hillebrand From the abstract, "A realistic ore deposition model to serve as a conceptual framework." Further, on page 246, "The first area of study was the Josephine peridotite, now identified as an ophiolite terrane, located in northern California and south-western Oregon (Fig. 3). Here, it was felt that we could test the models shown in Figs. 1 and 2 and, if successful, expand the model and test it in other chromite districts in the US and around the world." My comments refer only to chromite deposits in Europe and the Middle East. First, I question that may chromite deposits occur in the idealized ophiolite section shown in Fig. 1. Second, although some podiform deposits (referring to morphology) have been important (Guleman, Turkey, for example), the stratiform deposits are of greater importance in tonnage and frequently grade. Examples include Nada, Yugoslavia; Bulqiza, Albania; Xerolivado, Greece; Saranovsk, Russia; and Abdasht, Iran. Reply by J.C. Wynn Mr. Hillebrand raises two issues that deserve a serious response. One issue is basically subjective and the other is ultimately political. First, the question of where (and how many) podiform chromite deposits are found in the idealized ophiolite section of Dickey (1975). The Dickey model is still perhaps somewhat controversial (Panayoutou, 1980), but our experience in the Josephine ophiolite of northern California (Wynn, 1980; and Albers, 1983) shows that the model works well there. Virtually all the chromite is found in dunite lenses in the tectonite peridotite (harzburgite). Since there are few complete ophiolites exposed in the world, the model will probably never satisfy everyone. The degree of acceptance is a function of any individual's subjective experience. Second, it is well known that stratiform chromite contributes more than 95% of the chromite reserves presently known in the world, and it could be reasonably argued that there is no point in exploring for or exploiting podiform deposits further. The title of the paper, however, was in part 'strategic minerals geophysical research'; chromite is considered a strategic and critical mineral of the US and many other industrialized nations. Stratiform deposits in South Africa and Zimbabwe account for most of the chromite reserves in the world. Unfortunately, experience in modern times with substantial price fluctuations and even resource cartels dictates the wisdom of identifying and maintaining a national chromite reserve, irrespective of the cost. An improved exploration methodology is an essential element in this strategic objective. References Albers, J.P., 1983, "Geological and Geophysical Studies of Chromite Deposits in the Josephine peridotite, California and Oregon," US Geological Survey Bulletin 1546 A-D, 118 pp. Dickey, J.S. Jr., 1975, "A Hypothesis of Origin for Podiform Chromite Deposits," Geochimica et Cosmochimica Acta, Vol. 39, pp. 1061.1074. Panayiotou, 1980, Proceedings, International Ophiolite Symposium, Cyprus, 1979, 781 pp. Wynn, J.C., 1980, "Exploration Geophysical Methods and Strategies, and Their use to Locate and Assess Small Mineral Deposits," Chapter 12 of Meyer and Carmen, eds., The Future of Small Scale Mining, McGraw-Hill, New York, pp. 75-83.

Jan 12, 1983

By VASU GANGRADE

Large-opening underground stone mines pose significant ground control challenges, including the risk of massive pillar collapses. These collapses can result in dangerous air blasts characterized by tremendous force and high velocity. Estimating the velocity of these air blasts proves challenging due to the absence of accurate air velocity instruments near the mine portals. To address this issue, this paper proposes a novel approach that leverages closed-circuit television camera footage from the mine. Specifically, it employs the optical flow algorithm implemented in Python to estimate the velocity of the air blasts, providing a valuable tool for assessing and mitigating risks in such mining environments.

Feb 1, 2024

By William G. Pariseau

The flexure of geologic strata, a phenomenon of inter- est to geologists and mining engineers alike, is examined as a sheet bending problem' in Coulomb plasticity. Formulae for the distribution of stress, strain and displacement increments, volume change, change in the length of the central surface and power of dissipation, as well as for the neutral surface shift are given. Strains of any magnitude are considered. The analysis shows that deeply buried strata may bend and develop "tensile" cracks under generally compressive states of stress. It is also shown that bed separation and high capacity props are desirable in mechanized longwall mining, a result in keeping with operating experience. Although speculative at this time, the analysis provides a rational working hypothesis as regards the problem of strata flexure and control.

Jan 1, 1968

By R. Mathur

Cu isotope fractionation in low-temperature aqueous environments has been well documented. Here Cu fractionation was applied to two distinct, yet related, mining problems. First, an exploration geology application, where copper isotope fractionation was measured in oxidized leach caps, chalcocite enrichment blankets and hypogene mineralization in three porphyry copper deposits located in the southwestern U.S. Cu isotope patterns exist in a vertical distribution within the mines, coupled with distinct relationships with the Cu grade. Second, a hydrometallurgical application, where copper isotope fractionation was measured in leach fluids, feed and residues from a quick leach test (QLT) on Cañariaco, Peru ores. The results indicate the relative proportions of the minerals providing Cu during leaching. Interpretations of the QLT test measurements indicate covellite is the dominant ore mineral providing Cu during leaching. Both applications clearly demonstrate the use of the Cu isotope technique to understand low-temperature aqueous processes involving copper.

Jan 1, 2012

By T. Cienski

The paper presents and discusses the results of a detailed study conducted on the subject of energy consumption in the comminution of industrial minerals. The study was based on pilot circuit testing, plant operating data collection, detailed equipment data and literature research. The areas covered by investigations include: high efficiency classification; air classifiers for cement grinding circuits; grinding aids in dry grinding: dry grinding circuit, control based on particle size measurement. Results obtained indicate a large potential for the reduction of energy consumption, in particular in the traditionally high cement clinker grinding circuits. Better classification techniques and correct application of grinding additives can significantly reduce power used per ton of product and also substantially increase grinding circuit output.

Jan 1, 1990

By S. Miller, A. Krasner, M. Sizintsev, S. Schafrik, H. -P. Chiu, J. Sottile, A. Rajvanshi, Z. Agioutantis

In recent years, a great deal of effort has been put into automating mining equipment with the goal of improving worker health and safety and increasing mine productivity. Significant progress has been made in automating mining equipment such as load-haul-dumps and drills in underground environments where global positioning systems are unavailable. This paper addresses automating the task of positioning the shuttle-car (SC) under the continuous-miner (CM) coaldischarge conveyor during cutting and loading operations. A stereo depth camera is mounted on the SC. Machine learning based algorithms are applied on the camera’s output to identify the CM discharge conveyor and segment the scene into various regions such as roof, ribs, and personnel. This information is used to plan the shuttle car path to the CM discharge conveyor. The approach currently uses a 1/6th scale continuous miner and shuttle car in an appropriately scaled mock mine

Mar 2, 2022

Mine planners must select a single pit for design with the knowledge that the grades on which this selection is made are uncertain. This uncertainty is often ignored through the use of deterministic models of grade. This makes the mine planner?s job simpler but does not necessarily lead to the ?correct? or ?best? selection. Grade uncertainty is typically modeled with conditional simulation, which generates multiple possible realizations of grade that are equally probable (or improbable). M ethods for incorporating grade uncertainty into mine planning to date have either been perceived as being too complicated, not accessible or too time-consuming. This paper proposes a simple and efficient modeling approach to incorporating conditional simulation into pit optimization, which would be able to be applied in currently commercially available software. An example for R esolute M ining Ltd.?s Syama gold project in M ali shows the range of ore, grade and value outcomes associated with generating pits through a variety of methods.

Jan 1, 2013

By J. K. Wilmshurst

Absorption, emission and reflection techniques for the study of [molten] inorganic materials at high temperatures have been critically examined. In general, the reflection technique is the most satisfactory for tine study of pure materials, while the absorption, and possibly also the emission techniques, may be useful for studies of certain dilute solutions. In the present investigation infrared emission spectra for sodium nitrate and silver chloride were obtained together with absorption spectra derived from reflectivity data by the method of Robinson and Price for sodium nitrate, silver chloride, lithium and potassium fluoride and their 1:2, 1:1 and 2:1 mixtures and for solutions of zirconium tetrafluoride in lithium-potassium fluoride (1:1) and sodium-potassium fluoride (1:1). It is concluded that vibrational spectroscopy cannot give unambiguous information concerning the existence of complex ions in fused salt, mixtures.

Jan 1, 1963

By K. T. Stafford, N. A. Iverson, V. T. McLemore

Southwestern New Mexico is part of a large belt of Late Cretaceous to Eocene copper porphyry deposits found in Arizona, New Mexico, and Mexico. These deposits are the result of arc magmatism that occurred during the Laramide orogeny. Recently, attention has been brought to other commodities that can be extracted as by- and co-products, many of which are critical minerals. A new compilation of the geochronology of these deposits shows two main pulses of magmatism that produced mineralized deposits and, along with new dates by the author, shines new light on the geologic history of these deposits and the role it plays in critical mineral abundance.

Feb 1, 2024

By Jr. Bacon

Kaolin clay is one of the yeoman minerals. It sees duty in almost every aspect of our lives: -in and on most paper products (from modern newsprint to National Geographic and packaging board) sometimes as much as 25% (by weight) of the product -40% of the tile (ceramic, rubber, and linoleum) you walk on. -15 % of the tires you ride on, -30% of the fiberglass filaments in circuit boards, bathtubs, boats, doors, and more, -25% of many housepaints, adhesives, grouts, caulks, and putty -30% of sparkplugs, power insulators, dinnerware. and toilets, -50% of most catalysts (both cracking and emission control) -20% of cosmetic powders. -20% of wire insulation, and animal feed to rocket insulation!

Jan 1, 1993