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By Paul Dean Proctor

The known northern ore zones of the New Lead Belt of Southeast Missouri extend to the drainage divide between the Meramec River draining north and east and that of the Black River draining southward. Intensive geochemical studies related to the environmental impact of the new mining area have been carried out in the vicinity of some of the newly developed mines, mills and smelter complexes (Bolter,1970; Gale, et al, 1973; Wixson, et al, 1969, 1977). Other investigations have related to fringe studies of the Northern New Lead Belt and the possible additions of heavy metals to the surface waters, stream sediments and selected aquatic life (Proctor, et al, 1975, 1976). Similar studies have been completed in the Joplin area in the Tri-State district, and in the fringe area near Springfield, Missouri (Proctor, et al, 1974). A surface geochemical study is currently underway on the lead-zinc-copper-cobalt-nickel province near Fredericktown, Missouri (Proctor and Sinha, 1977). This report summarizes some of the distribution patterns of heavy metals in the waters, stream sediments and selected aquatic life in the Upper Meramec River drainage basin just north and west of the known northern portions of the New Lead Belt of Southeast Missouri. The region studied includes the site of the proposed and somewhat controversial Meramec Dam and the reservoir site behind it. Some 3905 km2 (1508 mi2) are included within the drainage basin of the Upper Meramec River. Six distinct drainage areas are included within the drainage basin; 1) a combined, lightly industrialized and farm area around Rolla and Salem, Missouri representing the Dry Fork drainage; 2) a primitive, mostly forested area with some farms and cattle rancheseast and north of Salem, Missouri comprising the Upper Meramec River

Jan 1, 1977

By G. Guzman, L. Sevilla, M. Botz

"Newmont Mining Corporation operates the Yanacocha mine in Perú and the gold milling section of the property includes a Sulfidization-Acidification-Recycle-Thickening (SART) plant to remove copper from pregnant leach solution. Since its commissioning in 2008, the plant has been intermittently operated as needed to remove copper upstream of a carbon adsorption circuit. However, starting in 2015 Newmont expects the plant to operate on a more continuous basis in response to higher copper ores that will be processed in the gold mill. In anticipation of this, Newmont conducted a campaign in May 2014 with stockpiled high-copper ore to evaluate performance of the SART plant with elevated levels of copper in feed solution. Results from the campaign demonstrated the SART plant is capable of efficiently treating high-copper leach solution. During the campaign, leach solution copper levels ranged from about 100 to 700 mg/L, and copper removals ranging from about 56% to +99% were achieved. The median copper removal efficiency observed during the campaign was about 94%. The primary plant modification determined necessary following the campaign was the need to improve consistency with sulfide dosing. INTRODUCTION Copper removal from cyanide leach solution can be affected through the addition of sulfide at acidic pH to precipitate copper sulfide as a solid. There has been renewed interest in the process in the past several years due to the increasingly common issue of high copper levels in cyanide leach solutions. The term Sulfidization- Acidification-Recycle-Thickening (SART) is used as an acronym for the process according to the primary unit operations utilized. At a pH of approximately 4.0 to 5.0, the addition of soluble sulfide to a copper-bearing leach solution will result in the precipitation of copper sulfide (Cu2S) solid. The overall acidification and sulfidization reaction is (assuming the use of sulfuric acid for pH adjustment): 2Cu(CN)3-2 + 3H2SO4 + S-2 ? Cu2S(s) + 6HCN(aq) + 3SO4-2 The above reaction is written relative to the copper-cyanide complex 2Cu(CN)3-2, though analogous reactions also take place with the other common copper-cyanide complexes Cu(CN)2- and Cu(CN)4-3. Sulfide in the above reaction (S-2) is normally supplied as sodium hydrosulfide (NaHS) purchased in solid or concentrated liquid form. Two characteristics of this reaction that are beneficial to a leaching operation are: 1. Copper is removed from solution as Cu2S (synthetic chalcocite) solid, which can then be sold to a smelter for its copper value. 2. Cyanide that is complexed with copper in the leach solution is released as free cyanide, thereby regenerating cyanide that can be recycled to the leaching operation for continued use."

Jan 1, 2015

By Shannon Seitz, Qingwen Shi, Junfeng Pan, Shuwen Wang, Brijes Mishra, Shaohong Liu

Delayed coal bursts in deep coal mines have caused significant fatalities and economic losses in recent years. Instead of occurring right around the advancing face, this particular type of coal burst is characterized by its occurrence at a certain distance behind the advancing face. To better understand the mechanism of a delayed coal burst, we used borehole camera, electromagnetic CT, and borehole deformation monitoring device to observe the fracturing and deformation process of an advancing entry’s surrounding coal in the field. Borehole camera detection showed a zonal disintegration phenomenon in the advancing entry’s surrounding coal. Electromagnetic CT detection showed that zonal disintegration developed within 14 days of excavation. Borehole deformation monitoring indicated a deformation rate difference between the intact zone and fractured zones. The deformation rate difference was observed to increase with time and cause increasing elastic energy accumulation in the intact zone. The cumulative elastic energy in the intact zone finally caused a delayed coal burst in the entry. Sensitivity analysis of the cumulative elastic energy was conducted based on a thick-walled model deduced from field detection. The model shows that the smaller thickness of the intact zone brings higher elastic energy in the intact zone. This investigation provides an improved understanding of delayed coal bursts in deep coal mines.

Oct 19, 2021

By A. D. Ajak

A complete mining cycle involves digging, loading, hauling and dumping of the materials. Moving the ore from the pit to the crusher or to the waste dump requires access routes, which are termed haul roads. These roads have to be designed, constructed and maintained. A review of the literature indicates a common consensus among researchers that there should be a balance between haul road economics and safety of the road users. However, there is no universally accepted theory on the design of haul road geometry and, in particular, road dimensions. The current industry practice is based on empirical data and rules of thumb developed by engineers. Therefore, this paper will use the overlooked and less valued branch of mathematics, arithmetic progression, to derive a road width equation. It is beyond the scope of this paper to discuss all road design components. The focus will be on the geometric aspects, which more often have a direct impact on road safety. In this paper, the current design practices and techniques for haul road geometrics design will be explored, using arithmetic progression to formulate road width equations, case examples to apply the equation and then validating the results with conventional techniques that have confirmed the reliability of road width equations, thus eliminating use of tables during design.

Jan 1, 2012

By William S. Fyfe

The world's biomass with its species-specific ability to concentrate metallic elements must provide one of the dominant concentration and transport systems for such elements. Given that about thirty elements are now considered bio-essential, for all these biomass may control their environmental behavior. Life appears to be present in almost all places where liquid water is present at temperatures near 100°C or below. In the surface environment a very large array of simple minerals are produced in living cells and such processes can lead to economic concentrations. Because of the specific nature of bioconcentration of elements, in all environments where biomaterials accumulate, interesting metal concentrations may occur or the molecular fragments from bio-degradation may allow specific metal transport and concentration. The scale of biological-inorganic interactions on our planetary surface is still inadequately appreciated.

Jan 1, 2013

Ground falls (roof and rib) have historically been responsible for nearly 50% of all fatalities in bituminous underground coal mines. In recent years, the number of some annual ground fall fatalities has approached zero, indicating that significant progress has been made. On the other hand, the twin disasters at Crandall Canyon in 2007, in which nine miners perished in violent coal bumps, provided a stark reminder that complacency is premature. One important success has been a great reduction in the number of miners killed inby roof supports. Throughout the 1990s, these accounted for nearly half of all roof fall fatalities, but there have just been two inby incidents since 2005. Progress has also been made in pillar recovery, where there has been just one fatal incident since 2005. On the other hand, more than 300 miners continue to be injured each year by rock falling from between supports and 100 more are injured by rib falls. Together, these two categories also account for a large percentage of recent ground fall fatalities available technologies such as roof screen, rib bolting and inside control roof bolters could reduce injury and fatality rates if they were used more widely. Further advances in these areas will likely be the next big advance in ground control safety.

Jan 1, 2011

By John Durkin

A system based on seismic techniques has been developed to detect and locate men trapped underground following a mine disaster. Both theoretical and field studies have been used to generate models to predict the performance of the system. For a strong source, it is almost certain that the miner's signal will be detected if the geophone array can be positioned over a likely area of entrapment. After signal processing, it is highly likely that the location of the miner can be determined within an accuracy of 100 ft (30.5 m). The system is presently operational in a state of readiness in the event of a mine disaster.

Jan 1, 1980

By E. G. Cauda

Diesel engines are a major source of underground miners? exposure to nitrogen dioxide. In an effort to reduce the exposure of underground miners to regulated and unregulated diesel emissions, primarily particulate matter, mining companies in the U.S. are retrofitting existing and introducing new engines with various exhaust aftertreatment technologies. Different aftertreatment devices, or changing the operating temperature of a selected device, can have unexpected effects on the concentration of nitrogen dioxide emitted by a diesel-powered piece of equipment. This paper provides an overview of the effects different exhaust aftertreatment technologies available to the mining industry have on no2 emissions.

Jan 1, 2010

By I. J. Lin

The effect of various types of structural modification on the critical micelle concentrations (CMC) and hydrophile lipophile balances (HLB) of certain surfactants has been considered. Using the concept of effective chain length for the substituted species, an index of hydrophobicity (I) has been defined. It is hoped that such an index will allow one to choose surfactants for particular purposes in a less arbitrary fashion than heretofore.

Jan 1, 1973

By T. Dombrowski

Acid-activated montmorillonite is used worldwide as a catalyst and as a sorbent for the enhancement and purification of petroleum products as well as vegetable and animal-based fats. The solid-acid character of the activated montmorillonite is imparted by the manufacturing process, giving it unique properties that are exploited in these industries. Several international companies and a multitude of local clay producers are focusing on improving the efficiency of their standard and specialized products. This paper will describe the use of acid-activated montmorillonite in traditional sorbent applications, as a solid acid catalyst, and other new uses.

Jan 1, 1997

By L. E. Eary, Andy Davis

The evolution of pit lake water quality depends on the lithology and hydrologic characteristics of the ultimate pit surface, the availability of buffering capacity in the wall rock vs. oxidizable sulfide content, the alkalinity of recharging groundwater and the evapo-concentrative characteristics of the system. This paper assesses the geochemistry of 11 existing pit lakes, ranging from the acid Red Hill and Berkeley pit lakes (pH 2.6 to 2.8) to the alkaline Yerington pit lake (pH 8.45). Predicted pit lake chemistry is similar to that in existing pits, with long-term chemistry lying on a geochemical continuum between end members that consist of influent calcium bicarbonate groundwater and naturally occurring sulfate-rich evaporite playa lakes.

Jan 1, 1998

By Rihab Guellala

In Tunisia, the Paleocene-Eocene series has an important socio-economic interest. It contains profitable oil and water accumulations. Moreover, it encompasses phosphate reserves. The present study uses seismic reflection prospection and borehole data for the reconstitution of the Paleocene-Eocene deposit structure in the Jerid area (southwestern Tunisia), a crucial step for the phosphate exploitation. Firstly, lithostratigraphic correlations incorporating water and petroleum wells were established according to different directions for a tentative approximation of the Paleocene- Eocene deposit geometry by following their lateral evolution. To give more details, seismic reflection profiles were interpreted in the second step. The Paleocene-Eocene formations were associated with their corresponding reflectors on the closest seismic profile using the relation of time and depth in petroleum wells. Analysis of lithostratigraphic correlations shows notable variations in the Paleocene-Eocene series thickness and depth. Seismic profile interpretation explains these variations by highlighting different buried tectonic features. The results confrontation reveals that the phosphatic deposit geometry in the Jerid area is mainly influenced by the (1) emergence of the Saharan platform and the Chott northern chain since the Late Cretaceous, (2) syn-sedimentary normal activity of E-W and NE-SW faults during the Paleocene-Eocene epoch, (3) reverse-reactivation of these faults, and (4) major Tortonian folding phase. This study can enormously enhance the Jerid area socio-economic development by presenting useful findings that may orientate the phosphate exploration.

Aug 15, 2021

By David D. Lambert

REE analyses of cumulate plagioclase from the PGE ore zone of the Stillwater Complex indicate that pressure fluctuations in the magma chamber acting on a single magma can- not be responsible for features such as the reappearance of Mg-rich olivine on the liquidus. The data is more consistent with a model involving multiple injection and mixing of geochemically distinct magmas. The PGE bearing sulfides of the J-M Reef are associated with such a re- appearance of olivine, indicating that the unusual location of the ore zone may be related to the addition of new magma, compositionally distinct from magmas that produced cumulates in the Ultramafic zone of the complex.

Jan 1, 1981

By J. Kretschmann, R. Amiri

"The Sangan iron ore mines (SIOM) in Iran are located in a remote area near the Afghanistan border. The SIOM deposit contains a geological resource of 1.1 Gt (1.2 billion st) of mostly magnetite with an iron (Fe) grade ranging from 27 to 61 percent. The Iranian government plans a stepwise development of SIOM in cooperation with private companies to satisfy the growing demand of the Iranian steel industry. Sustainable development is an influential ethical concept in mining all around the world. However, a successful realization of a sustainable development plan is not possible without a foundation on the core values and regarding the specific circumstances of the individual mining country. This paper introduces SIOM and describes sustainable development activities undertaken during its development. From the early stages, these activities have been realized to secure the acceptance of the stakeholders in the region. To evaluate their effects, indicators were filtered to the ones with the highest priority for the stakeholders. Moreover, Islamic values and Iranian regulations and their influences on SIOM were analyzed.Mining industry in Iran The Islamic Republic of Iran holds 68 types of minerals, including salt, sand and gravel, gypsum, chrome, lead, zinc, copper, coal, gold, iron, etc., with 33.5 Gt (37 billion st) of proven reserves and more than 51.7 Gt (57 billion st) of potential resources. Iran is ranked among the 15 major mineral rich countries (1). In accordance with the statistics published by Statistical Center of Iran (SCI), there were 5,316 active mines and 84,922 employees in the whole country in 2012-2013 (2) and, according to the statistics published by Central Bank of Iran (CBI) in 2011, the share of this sector in the gross domestic product (GDP) of the country was 1.2 percent (3)."

Jun 1, 2016

By D. P. Caplice

On behalf of the Ontario Water Resources Commission, I would like to express my sincere appreciation to your Institute for presenting us with this opportunity to outline the regulatory control programme as it relates to the mining industry in the Province of Ontario. In Canada, and particularly in Ontario, we are blessed with an abundance of natural resources. Fresh water in the form of lakes and rivers covers nearly 17 per cent of the area of the Province. (Total area of the Province of Ontario is 412,582 square miles.) The mining industry, which had its beginning in the early 1800's with a small iron ore plant, has progressed with the major discoveries of nickel and copper in 1883, silver in 1903, gold in 1908, iron in 1939 and uranium in 1953, to the point where, in 1966, almost one billion dollars in mineral wealth was mined in Ontario. Water, in spite of its great abundance and with due respects that it may become a natural resource worthy of export in the foreseeable future, has become increasingly precious in Ontario, particularly in the more urban areas in the southern part of the Province.

Jan 1, 1968

By C. Haycocks

The evolution of longwall mining is briefly traced from its inception in England in the 1620's. In the beginning this method recovered 90% of coal with roof closure controlled by packs and walls. Mechanization began with kerf cutting, crude face conveyors, and improved face support. Full face mining was accompanied by the introduction of self-advancing hydraulic supports. U.S. longwalls evolved a retreating system to recover blocks of coal outlined by room and pillar panels. Computer control combined with the most modern technology has greatly increased productivity. Past trends are used to predict future technological directions.

Jan 1, 1997

By Jerry L. Fuller

Fan performance graphs are generated by digital computer using two programs, RUN- FANS and FANPLOT. RUNFANS calculates fan performance data from stored specific-volume, specific-speed data for a given fan type with appropriate allowances for fan diameter, rotational speed and air density. FANPLOT accepts specifications for drawing the graph and accepts either user-supplied pressure-quantity data or RUNFANS- calculated data as input, Operational procedures for both programs are detailed and examples of their interactive query routines are included. The hardware necessary to generate the graphs is illustrated. Several hardcopy output options are discussed,

Jan 1, 1984

By M. S. Celik

The principal impurities in some feldspar ores are titanium and iron which impart color and in turn degrade the quality of the ore. The mineralogical investigations indicate that titanium element originates from mainly rutile with small amounts of sphene. Conventionally, fatty acids and particularly sodium oleate are extensively used in the flotation of colored minerals from feldspar ores with reasonable success. In this study, new reagents, oleoyl sarcosine and hydroxamate have been used to float colored impurities before and after magnetic separation. Oleoyl sarcosine is found to exhibit better results compared to fatty acids and hydroxamate. The mechanism of the action is elaborated on the basis of experimental data.

Jan 1, 1999

By Scott Rosenthal, Dave Gilkey, Theresa Stack, Daniel Autenrieth, Ciara Kremer

Jackleg drill operators are exposed to harmful levels of hand-arm vibration (HAV). Anti-vibration handles and gloves provide modest reductions in HAV exposures and forearm muscle exertion from the use of anti-vibration handles and gloves by jackleg drill operators. The goal of this pilot study was to investigate changes in HAV with the use of anti-vibration gloves and handles compared to forearm muscle exertion experienced by operators and measured with surface electromyography (EMG). Five subjects operated the drill under four different cases: no anti-vibration controls, anti-vibration gloves only, anti-vibration handle only, and simultaneous anti-vibration handle and glove use. Muscle exertion was expressed as a percent of maximum voluntary contraction (%MVC) and was compared using Welch’s ANOVA with Games-Howell post hoc comparisons. The case with both anti-vibration controls in use simultaneously (largest grip diameter) was associated with a mean %MVC of 36.13% during operation for all forearm muscles combined, which was significantly higher than that of the other cases (p < 0.05). There were no statistically significant differences in mean HAV exposures. The anti-vibration handle with anti-vibration glove case only increased the maximum allowable exposure time by 8 min as compared to the control case without any anti-vibration controls. These results suggest that the modest HAV exposure reductions from the use of anti-vibration handles and gloves may pale in comparison to the increased muscle exertion resulting from their use, and this trade-off among jackleg drill operators is a potential concern that warrants further investigation.

Jul 12, 2021

By Georgios Bartzas, Vasiliki Karmali, Konstantinos Komnitsas, Anna Kritikaki, Dimitra Vathi, Stylianos Tampouris, Arne Peys

Large volumes of slags, with varying mineralogical and geochemical characteristics, are produced annually by the ferrous and nonferrous metallurgical industry. Most of them are considered as potential secondary resources and may be valorized, following the principles of circular economy, for the recovery of critical elements, including energy transition metals. Apart from the economic benefits, valorization of slags may contribute to the competitiveness of the metal industry and the conservation of natural resources. Valorization also results in minimization of environmental impacts on soils and waters in slag disposal areas, due to the prevention of solubilization and subsequent migration of potentially hazardous elements. The present study utilizes ferronickel (FeNi) slag for the production of alkali-activated materials. The effects of the main experimental parameters, including sodium hydroxide (NaOH) molarity, silica/sodium oxide (SiO2 /Na2O) molar ratio in the activating solution, precuring and curing time, curing temperature and aging period on several properties of the final products, are assessed.

Apr 1, 2025