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By Deborah A. Peacock

"Outer space technology and exploration have reached a tipping point, so that mining and mineral processing in outer space is now a certainty and not a dream. Several competing companies worldwide are on the way to building spaceships to land on the Moon and eventually mine the Moon and asteroids for volatiles, rare earth metals and Helium-3.The Google Lunar XPrize offers a $30 million prize1. China has recently landed a spacecraft on the Moon. The European Space Agency, with cooperation from the United States, has landed a spacecraft, Philae, on a comet. And, Mars One is planning a one-way trip to establish a settlement of humans on Mars.How and why are the Moon and asteroids and their resources of interest to private space industry companies? Why are the Moon and asteroids viewed as a potential business venue?Geology of the Moon and asteroids — Why do we want to mine there?Space enterprises are actively working toward establishing and operating lunar and asteroid mining locations for resource extraction, resource processing, conversion to salable products and distribution of the products and services in space and to Earth and beyond2.Forty-five years ago, the Apollo manned missions to the Moon returned rocks and regolith to Earth, which were studied and analyzed. What they found was that the Moon contains valuable minerals and resources. These minerals are largely due to meteor and asteroid impacts, which have, over eons, created this mineral-rich regolith. These impacts have occurred on Earth as well, for billions of years, particularly early on in the history of the solar system. However, on Earth, wind, water and vegetation have erased most of these impacts. On the Moon, in contrast, the only weathering is caused by subsequent impacts and the solar wind."

Jan 1, 2017

By Hassan El-Shall

Treatment of plant effluent including waste water and associated soluble and insoluble substances, is of a primary concern of many process industries including mineral processing operations. The major objective of such treatment is the removal of such impurities which can interfere with the process through the use of recycled water, and/or to comply with environmental ordinances. For example, Ramirez and Clements (1978) state that molybdenum contents in the range of 19 mg/1 eventually poison ion exchange resigns used for the extraction of uranium. In addition, recent restrictions by the EPA on molybdenum discharge values for mining waste water necessitate removal of this metal to (0.5-1.0 mg/1).

Jan 1, 1984

By Norman K. Olson

A geologic investigation of mineral resources in South Carolina first began in 1825 when the General Assembly authorized Lardner Vanuxen to conduct a "Geological and Mineralogical Survey of South Carolina." Vanuxen, South Carolina's first State Geologist, reported in 1826 on the limestones (marble) of the Piedmont which during those early years, were burned in many shall, scattered kilns in the region wherever suitable raw material was available. He also mentioned the possibility of using marl from the Atlantic Coastal Plain province for direct application and enrichment to the soil. Since before the year 1844 industrial minerals in South Carolina have been commercially produced literally from A to Z, asbestos to zircon. The first pub¬lished reports of actual commercial production, not just an occurrence, are referenced in Table 1 for 33 known industrial minerals and rocks in South Carolina. Known or suspected occurrences of undeveloped non-metallic mineral resources in South Carolina await future verification by geologic mapping, sampling (including coring), possible beneficiation, and market analysis. These industrial minerals and rocks include, but are not limited to, special, clay minerals (e.g. bentonitic clays, zeolites and others), sillimanite, argillite (lightweight aggregate), kaolin (alumina) and marl (underground storage and tunneling medium). In addition other non-metallic minerals, once mined but still worthy of reconsideration, include topaz (industrial), heavy minerals, barite, feldspar, and monazite. Finally, possibilities for new reserves, as an expansion of existing mine output, might develop for fuller's earth, limestone (lime), sericite (finely divided mica), vermiculite, kaolin (paper coating and filling, other filler), and metallurgical gravel. Official South Carolina data from the U. S. Bureau of Mines for 1974 indicated a total value of mineral production of $105.2 million. During 1974 production consisted of cam-on clays, (brick and tile), fuller's earth, kaolin and vermiculite

Jan 1, 1977

By Peter Cammack

Where raw coal from a mine is treated in dense medium separators ash in the washed product is generally very consistent, provided control of the medium suspension is maintained at a given specific gravity. When, however, the washing process is a Baum jig or other similar apparatus, making a separation at rather arbitrary gravities, the control of the product ash is less accurate, particularly in those cases where the design capacity of the washbox is exceeded by the load of high ash fines. In either of these cases an instantaneous measurement of ash while not essential would be desirable, to check the quality of the washed product and provide operator or management with instantaneous warning of changes in ash. Nearly 60% of all British coal mined goes for electricity generation, to burn at 17% ash, and since the overall average ash content of raw coal as mined is about 30% and varies within a range of 18 ? 40%, incombustible material has to be removed. The ash specification could be met either by total washing, or by washing part and blending the clean coal produced with the remaining untreated coal. Some plants use a straight tonnage split, but generally speaking in Britain it has been found more economical to screen and wash the oversize only. In either case for effective quality control in blending an instantaneous determination of the ash content of the product as it is made has been found essential, since standard ash determination by pyrolysis methods is lengthy and provides information too late to be used in the control of plants blending at the rate of 1000 ton/h.

Jan 1, 1976

By G. L. Smit

The Buffelsfontein Gold Mining Company is situated in the Klerks-dorp district of the Province of the Transvaal in the Republic of South Africa, approximately 100 miles west of Johannesburg. Gold production commenced in January 1957 and Uranium treatment of residue slimes as a by-product started in July 1957. The mining property is 5435 mining claims in extent, the equivalent of 7,988 acres or 12.5 square miles. The mine was initially exploited by the Pioneer Twin Shaft System, consisting of a 26 feet diameter down-cast shaft and a 22 feet diameter up-cast shaft, sunk in the north-west area of the mine to cater for the hoisting and ventilation requirements for a milling rate of 150,000 tons per month.

Jan 1, 1964

By J. F. Hutwelker

A pilot plant was constructed and operated to investigate the column flotation of 20 x 200 mesh North Carolina phosphate ore, using high throughput, high solids operating conditions developed at the NCSU Minerals Research Laboratory. Flotation was performed at 45% solids in a 9.5 cm (3.75 in.) diameter by 2.26 m (7.4 ft.) tall column at throughputs of 19.1 t/hr/m2 (2.0 stph/ft2) and 31.7 t/hr/m2 (3.3 stph/ft2). Recoveries in excess of 98% of the phosphate value were obtained at the lower throughput -- while obtaining concentrate grades containing over 28% P205 (61.2% BPL) at that recovery. Recoveries of about 95% of the phosphate value were obtained at the higher throughput, while making a concentrate averaging 27.6% P209 (60.3% BPL). In addition, a better understanding of the variables governing the column flotation of coarse nonmetallic minerals was gained. Low air flow rates adversely affected concentrate grade at the lower throughput. At the higher throughput, phosphate recovery decreased at an elevated air flow rate. An unexpected result of the study was the effect that frother type had upon phosphate metallurgy. Use of Nottingham Econofroth 925 provided better flotation selectivity than American Cyanamid F-65 at the low throughput. This is significant since the high' throughput tests were conducted with F-65 exclusively. It is reasonable to expect further improvement in high throughput performance when the optimal frother type and dosage are determined.

Jan 1, 1993

By Tom B. Corry

INTRODUCTION Located approximately 48 km (30 miles) south of Dallas, Texas, use to be the site of the Superconducting Super Collider. For those of you unfamiliar with the project, this was a multi-billion dollar project taken on by the U.S. Government for the further advancement of technology, medicine, and science. Major components of the project consisted of a Linear Accelerator known as the LINAC; three accelerating rings known as the Low Energy Boosters (LEB), Medium Energy Booster (MEB) and the High Energy Booster (HEB); the East and West Campuses where the Inner Reactor Halls would have been located; and the 87 km (54 mile) main collider tunnel. Unfortunately, this all came to an end on December 6, 1993, with the termination of the project due to the Government's cancellation of funds. This paper will deal with the two of the underground contracts before the termination. These two contracts were the 1122 contract which ran from N25 to N40 and the 1130 contract which ran from N40 to N55. (See figure 1) The 1122 contract was awarded to us in July of 1992 and consisted of the excavation and support of six (6) shaft varying in diameter from 5.5 m (18 feet) to 8 m (26 feet) and ranging from 39.6 m (130 feet) to 61 m (200 feet) deep and the driving of approximately 13,100 m (.43,000 If.) of main collider tunnel. Our second contract, the 1130, was almost identical to our first

Jan 1, 1995

By J. Kou

The adsorption process, density and structural property of the oleate layer adsorbed onto a hydroxyapatite (HAP) surface at six different concentrations and three pHs (pH 8, 9 and 10) have been studied using the technique of quartz crystal microbalance with dissipation (QCM-D). The present study demonstrated the versatility and accuracy of the QCM-D for surface adsorption characterization. The real-time measurements of frequency and dissipation shifts with a hydroxyapatite-coated sensor revealed changes in the hydroxyapatite surface during the entire adsorption process. Chemisorption and surface precipitation of sodium oleate were also observed on the surface of hydroxyapatite through the use of Fourier Transform infrared spectroscopy(FTIR). Chemisorption dominated at low concentrations and high pH values and formed a rigid and thin adsorption layer. Surface precipitation of calcium oleate and micelles dominated at concentrations higher than critical micelle concentration (CMC) and lower pHs and formed a thick but dissipated adsorption layer with a high hydration level. Three distinct adsorption behaviors were identified from the different slopes of ?D-?f plots. The adsorption density was less than a monolayer at concentrations <0.164 mM, but increased significantly at concentrations higher than 0.821 mM at all three pHs. The critical concentration at pH 8 was 0.33 mM, which was lower than at pH 9 (0.821 mM) and pH 10 (3.3 mM).

Feb 1, 2012

By M. Pillay

INTRODUCTION Heat stress continues to be a safety concern in underground mining. This is due to a number of reasons including increasing depths of mining, increased levels of heat generated from machines, ventilation systems being constrained from providing suitable levels of airflow and others. In order to assess if a thermal environment is safe for miners under normal or modified work arrangements, or to specify stop work conditions a heat stress index is used to guide decisions. Historically, a number of heat stress indices have been developed and applied in underground mines. These can be classed under three broad headings; single measurement, empirically based and rational indices. Do any of these indices perform better than the others? Which one allows simple determinations and decisions to be made in the mine? This paper aims to provide answers to these questions by comparing and contrasting three indices; effective temperature (ET), simple air cooling power (ACP) and Thermal work limit (TWL) for a range of typical mining wet and dry bulb combinations? The paper concludes with the identification of areas for future research. BACKGROUND Heat stress causes discomfort, increases physiological strain, decreases productivity and performance, and contributes to increased incidents [1]. Effective management and control of heat stress is particularly important in mining where hot working conditions are very common [2]. Heat stress index is a common indicator that is used by mine safety advisors and managers to guide decisions about safe work practices in mining under normal or modified conditions. According to Howes and Nixon [3] A safe heat stress control strategy for an underground mine has three elements: • Application of an environmental measure which reflects physiological strain with sufficient accuracy for the range of conditions encountered underground. • Acceptance of a functional relationship between the environmental measure and human performance which is used to optimise the environmental conditions achievable with either ventilation or ventilation and refrigeration. • A management control strategy based on the environmental measure which is designed to ensure that work in environments where excessive physiological strain may occur is prevented and corrective action is initiated. The link between these elements is an environmental measure that reflects the physiological strain a worker is subjected to. Since the turn of the twentieth century various indices of thermal stress have been developed (McPherson [4], Howes and Nixon [3], Brake [5]). In selecting a suitable environmental measure or index one problem that must be addressed is the ease with which it can be physically obtained relative to it accurately reflecting the physiological strain. No index can be universally applied and there is no single correct measure or index. However if an index has provided adequate control in a particular circumstance, then it can be regarded as correct for that situation.

Jan 1, 2019

By R. E. Mitchell

The environmental impact assessment (EIA) is the accepted method for evaluating proposed mining and other industrial projects to obtain regulatory approval and to help companies plan for responsible development. Another increasingly common evaluation system for proposed projects is the environmental, social and health impact assessment (ESHIA). An ESHIA differs from an EIA for its generally more comprehensive and inclusive approach to evaluating potential impacts, such as on public health, and other features such as an ecosystem services approach to assessing biophysical and community impacts. An ESHIA may also be required by certain lenders for financing major projects. In this paper, EIA standards for the province of Alberta, Canada are discussed and compared to ESHIA. It concludes with several recommendations for consideration.

Jan 1, 2012

By T. A. Farr, I. A. Gibbs, F. Guevara, S. R. Simms, G. Nojima

This paper describes an installation of a medium-voltage adjustable frequency motor drive (AFD) on a high starting torque regrinding mill. This type of application is typically found in the mineral industry dealing with hard ore. The AFD electrical architecture is introduced from line to load. The type of closed loop encoder feedback motor control algorithm is briefly described. The results of the AFD motor identification auto-tuning are compared against the manufacturer’s supplied data. The motor drive performance results are shown for pre-ramp DC fluxing, high starting torque with overload current, excessive load torque stall condition, and blocked rotor. The instrumentation and arrangement for the two watt-meter method to capture low frequency data are presented. The data shown is from the input power quality meter, the AFD computer tool, the output motor protection relay, an oscilloscope, and load shaft connected strain gauge (rotating telemetry for torque assessment). These types of high starting torque constant torque loads are found in mining and process industry applications employing AC adjustable frequency drives. Using field results should help demystify the use of voltage matching output transformers in AFD applications including constant torque loads

Mar 2, 2022

By Bruce A. Kuyper

Routine core drilling at the Cove deposit failed to confirm gold-silver grades and length of intercepts observed in reverse circulation drilling. A drilling program was designed to ascertain whether the disparity was due to problems with reverse circulation drilling techniques, core drilling techniques, or the erratic nature of the gold-silver mineralization. Special sampling devices and core drilling methods were employed. Data obtained from core-reverse circulation twins showed that down-hole contamination during reverse circulation drilling accounted for much of the variation between reverse circulation and core drill results. Down-hole contamination occurred as a result of high ground-water inflows eroding friable vein material from hole walls.

Jan 1, 1991

By Evan J. Owen, Virginia T. McLemore

The Zuni Mountains, located in Cibola County, New Mexico is an uplifted area that exposes Proterozoic igneous and metamorphic rocks overlain by Permian and younger sediments. Sedimentary-hosted Cu deposits and fluorite veins in the district have recorded production, but other deposits exist. Proterozoic ultramafic rocks may host Ni and PGE. A recent regional stream sediment survey collected 76 samples as part of an exploration geochemistry course at New Mexico Tech with the goal of assessing the critical minerals potential of the district. Whole rock and trace element chemistry of the sediment samples (<2 mm) show a variety of critical minerals possibly worthy of future targeted exploration including up to 700 ppm As, 2100 ppm Ba, 26 ppm Bi, 25 ppm Co, 640 ppm Cu, 145 ppm Ni, 110 ppm Sb, 170 ppm V, and 500 ppm Zr. Positive correlation between Bi, As, Cu, and Sb suggest that these critical minerals are found together within copper veins related to shear zones in the district. Samples collected from streams that drained outcrop of mafic and ultramafic rocks were found to generally contain more Ni, Co, and V. Samples elevated in Ni will be reanalyzed for PGE.

Feb 1, 2025

By Patrick Scott, Germán Schmeda, Morgan Mullins, Liam Knudsen, Bradley S. Van Gosen, Carma A. San Juan, Nicholas A. Karl, Jeffrey L. Mauk, Clayton Forbush

The objective of the US Geological Survey’s mineral deposit database project (USMIN) is to develop a comprehensive twentyfirst century geospatial database that is the authoritative source of the most important mines, mineral deposits, and mineral districts of the US. Since May 2017, the project has focused on critical minerals. Data for critical minerals that are produced as products are relatively robust, whereas data for critical minerals that may be recovered as byproducts are commonly of much poorer quality. Similarly, more is known about critical minerals that occur in conventional deposits than where those critical minerals occur in unconventional deposits. For example, rare earth elements occur principally in deposits hosted by alkaline igneous rocks, but there is potential for their production from phosphate rock mining, which is less documented. Lithium (Li) has been recovered from pegmatites and brines, but other Li-bearing deposit types have been delineated that may go into production. Cobalt may be produced as a byproduct or coproduct from a wide range ofmineral deposit types, whereas rheniumis a byproduct of copper ore. Significant opportunities for research exist that could help identify new sources of critical minerals, and may also help increase production and recovery from existing sources.

Feb 8, 2021

By Tim O’Neil

Nearly 4,800 mining professionals and exhibitors occupying 580 booths attended the 2000 SME Annual Meeting and Exhibit, Feb. 28-March 1, in Salt Lake City, UT. The technical program included80 sessions and four specialty symposia: bulk material handling, control 2000, minor elements 2000 and plant operaters. Meeting highlights included the keynote session. Executive shared their perspectives on pivotal issues and approaches to address the challenges of the new millennium. SME has begun planning for its 2001 Annual Meeting, Feb. 26-28, in Denver, CO. The meeting carries the theme “2001 — A Mining Odyssey.” A call for papers has been issued and exhibit space is 80% reserved. For information, visit SME’s website, www.sme-net.org. Or write Box 625002, Littleton, CO 80162-5002,ph 800 763 3132 or 303 973 9550, fax 303 979 3461, or email meetings@smenet.org.

Jan 1, 2000

By Richard A. Grieve

A 63.5 metric tons per hour (70 TPH) demonstration coal preparation plant was constructed on the Iowa State University campus, Ames, Iowa, as a part of the Iowa Coal Project funded by the state of Iowa and administered through the Energy and Minerals Resources Re-search Institute. Processing equipment in the plant circuit includes a heavy media separator, concentration tables, separating and dewatering screens, and conveying equipment. Coal samples of size 907 metric tons (1000 tons) with sulfur contents ranging from 2.5 to 8.75% sulfur from seven mines in the state of Iowa have been pro-cessed in the plant. Sulfur reductions have averaged 35%. With ash reduction averaging 45%. Equipment for advanced fine coal beneficiation research is currently being installed in the plant to include a slurry pretreatment circuit, froth flotation, oil agglomeration, pelletization, hydrocyclones, advanced design thickener and disc filtration.

Jan 1, 1978

By Ingunn Opland, Silje M. Tinderholt

Drill and blast project in Norway’s capital. The contract consists of 7 rock caverns (350–950 m2), 9.2 km tunnels, and four shafts. With 110 blue-collar and 31 white-collar, the project produces an average of 16–21,000 m3 hard rock per week, with a total of 19 tunnel faces. Weekly, nine grouting rounds for water control, 800 m3 shotcrete, and 1,200 bolts are required, and 60 trucks leave the site pr. day. Challenges include blasting in densely populated areas, planning and coordination to maintain high production, obtaining a CEEQUAL certification of very good, and transporting rock on Oslo’s main highway.

Jun 13, 2023

By S. Iverson

Fall of ground accidents continue to be a source of injury in underground metal mines. MSHA accident statistics indicate that most rock fall accidents occur at a new face where drilling and blasting methods are used. Removing loose rock by scaling is imperative to removing the potential for rock fall injury. Detection of potentially loose rock could improve the scaling process and result in fewer rock falls. Infrared thermal imaging cameras were investigated as far back as 1966 as a tool for loose rock detection. Early on it was clear that sensitivity (e.g. detectable temperature increment) is a key factor in this application. Both pixel resolution and temperature resolution have greatly improved with modern instruments. This paper describes an evaluation of modern infrared thermal imaging camera technology to detect loose rock conditions at six underground metal mines in the western U.S. It was found that thermal images provide a high resolution visual discrimination between loose rock and intact rock. However, detecting loose rock was difficult in cases where the rock and ventilation air were at the same temperature. Loose rock was detected when rock was both warmer and cooler than the ventilation air temperature. Warm rock with cool ventilation air provided the best conditions for detection.

Feb 23, 2014

By V. T. McLemore

"Production of industrial minerals remains important to the rural economy of New Mexico. In 2014, some 240 mines were registered in New Mexico, including 25 industrial mineral operations and 189 aggregate operations. New Mexico leads domestic production of potash, perlite, zeolite, and travertine. Other production includes aggregate, humate, pumice, gypsum, salt, common and fire clay, scoria, limestone, fly ash, cement, magnetite, silica, and decorative stone. New Mexico has potential for additional production of industrial minerals. One company is exploring for garnet. Cretaceous black sandstones in the San Juan Basin have drawn interest for titanium, rare earth elements (REE), and zircon. Other REE deposits are being explored. REE-Th-U veins are found in the Gallinas, Capitan, and Cornudas Mountains and Laughlin Peak-Chico Hills. Recent exploration has occurred for beryllium in the San Mateo Mountains, Iron Mountain, and Victorio districts. Companies also are examining High-Ca limestone and High-Mg dolomite for potential development. Aggregate continues to be important in urban areas and along highways. INTRODUCTION Industrial minerals and rocks are literally the building blocks of our way of life and they are an exceptionally diverse and vital group of raw materials that underpin almost all aspects of human activity, infrastructure, and standard of living. Industrial minerals and rocks are used in the manufacture of many products, from ceramics to plastics and refractories to paper. Although industrial minerals permeate every aspect of daily life, their presence and their role are typically invisible. A widely used definition of industrial minerals and rocks is “any rock, mineral, or other naturally occurring substance of economic value, exclusive of metal ores, mineral fuels, and gemstones: one of the non-metallics” (Bates, 1975). This definition includes the important construction materials sector as well as specialized industrial minerals, but complex interactions between consumer industries produce a number of apparent anomalies to this definition. Some metals are included as industrial minerals because their use is industrial rather than as a metal. Sulfur is now predominantly extracted as a by-product of cleaning natural gas, one of the world's major energy fuels. Production of industrial minerals has been and remains important to the rural economy of New Mexico. Industrial minerals constitute nearly 40% of the more than $2.8 billion generated by mineral production in New Mexico in 2013 (Table 1, see APPENDIX). In 2015, some 240 mines were registered in New Mexico. This total includes 25 industrial mineral operations and 189 aggregate operations. New Mexico leads domestic production in potash, perlite, zeolite, and travertine. Other industrial minerals production from New Mexico includes aggregate, humate, pumice, gypsum, salt, common and fire clay, scoria, limestone, fly ash, cement, magnetite, silica, and decorative stone. Additional production statistics are in Harben et al. (2008). Major industrial mineral districts are shown in Figure 1."

Jan 1, 2016

By H. Cho

There is an indication that high-pressure roller milling promotes selective liberation due to preferential breakage along the mineral boundaries. A study was undertaken to compare the degree of liberation obtained by high-pressure roller milling with that of conventional ball milling. Coals with different HGI&apos;s were ground in a high-pressure roller mill and a ball mill to produce products with similar size distributions. The products were then subjected to float-sink separations to determine the degree of liberation. Also, the relative cleanabilities were compared by separating the ground products by froth flotation. The results from this study are presented in the paper.

Jan 1, 1994