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By James J. Broderick

In the production of Pig Iron - Limestone, Coke and Iron Ore pellets are changed to the blast furnace and reacted at approximately 2,800 degrees F. The resultant products are molten iron and a molten slag - not unlike lava. The molten slag stream is channeled into open pits, cooled with water, crushed and sized for various industrial applications. The production of steel from pig iron in open hearth, B0P, BOF and electric furnaces results in somewhat similar slags: but since free lime is normally the flux, the resultant slags are not satisfactory for use in cement pastes. When exposed to water, the lime slakes, expands by 250% and ruptures the concrete. Thus, the slag discussed first is Blast Furnace Slag composed of 30 to 40% Silica (SiO2) Alumina (AL202) 7 to 16% Lime (CaO) 32 to 45% and Magnesia (MgO) 5 to 15%. The oxides do not exist as free oxides but rather as silicates and alumino silicates which are chemicall inert. Since transportation costs limit the area of use, blast furnace slag can only be found in concrete products produced within 60 to 100 miles of a blast furnace operation. Even within these areas where slag is in heavy supply, quite often the use of slag is minimal for concrete aggregate and the major outlet is road base.

Jan 1, 1985

By Ronald J. Roman

A mathematical model was developed for the grinding and flotation section of Union Carbide's Bishop mill and this model was used to indicate how variations in grind, retention time, and calcite and fluorite content effects the mill capacity, tungsten units produced, and the grade and recovery of the scheelite concentrate. A model such as this is a starting point in determining the economic optimum running condition for a mining and milling operation and an example of this is given.

Jan 1, 1969

By W. G. Pariseau

A study of coal pillar strength was done at the Beehive Mine during a three year period, 1974?1977, in a cooperative effort involving the University of Utah, RE/SPEC, Inc., and the American Coal Company (Pariseau et al, 1977). The Beehive Mine is located in the Wasatch Plateau coal field in central Utah near Orangeville, Utah, where mines are developed from outcrops between steep canyon walls with topographic relief of a kilometer or so (3,600 ft). Coal is found in Cretaceous sediments that dip gently to the west. Detailed geology of the Wasatch Plateau is described by Doelling (1972). Mining was done in the Blind Canyon seam. An earlier Deseret Mine worked the Hiawatha seam that is lower in the stratigraphic column by about 36 m (120 ft). Mining progress and ownership changes occurred in time with mine mergers and name changes eventually to the collective Des-Bee-Dove label. At the Beehive Mine, depth varied with topography but was approximately 360 m (1200 ft) on average; seam thickness varied from 1.5 to 6 m (5 to 20 ft) and usually required two passes of the miner. The mine was eventually closed and finally reclaimed in 2003. Semborski and Oakley (2006) present a brief history of the mine and describe the reclamation work in some detail. Figure 1 shows the surface topography in the vicinity of the mine that is in the center of the figure.

Feb 23, 2014

By Ch. R. V. S. Nagesh, Ramesh Naidu Mandapati, Venkata Swamy Nalajala, Tondepu Subbaiah, Naga Jyothi Kothamasu

Leaching studies of magnesite obtained from Tamilnadu Magnesite Limited, Salem, have been carried out using hydrochloric acid leaching and percentage of magnesium chloride recovered was estimated. The variables considered in this study were the following: duration of leaching, volume percentage of hydrochloric acid, temperature, and pulp density. Percentage recovery of magnesium chloride increased with duration of the leaching, volume % of concentrated hydrochloric acid, and temperature. Percentage recovery of magnesium chloride decreased with increase of pulp density. The optimum conditions found to be pulp density (10%), hydrochloric acid concentration (30%), duration of leaching (2 h), and temperature (348.15 K). Iron was removed by treating the leach liquor with hydrogen peroxide and by raising the pH to 3.5–4. The purified leach liquor was subjected to spray drying for producing high pure magnesium chloride.

Jun 7, 2022

By C. Arthur Lefler

The Smoky Valley Mine is jointly owned by Louisiana Land and Exploration Company, Felmont Oil Corporation and Case Pomeroy Company. Copper Range Company, a subsidiary of L.L. & E. is the operator of the mine. The mine is located about 60 miles (100 km) north of Tonopah, Nevada on Highway 376 (formerly 8A) in the Big Smoky Valley on the western flank of the Toquima Mountain Range In the shadow of Mount Jefferson. The mine is at an elevation of about 6100 ft. (1860m) and is situated on the southwestern flank of Round Mountain, the hill for which the town of Round Mountain is named. The ore is a rhyolitic iglmbrite with coarse gold occurring along fractures and with fine microscopic gold disseminated in the rock mass. Minor silver is associated nth gold. Annual mining is planned at 5.8 million tons (5.3 million tonnes) per year with 2.2 million tons (2 million tonnes) as ore (7,000 tons or 6,400 tonnes per day).

Jan 1, 1981

By Lawrence E. Mannion

In southwest Wyoming lies buried the world's largest source of natural sodium carbonate, or soda ash. Perhaps a hundred billion tons of trona (sodium sesquicarbonate) are contained in ancient lake beds in the Green River basin'). There the Green River Formation encloses more than 40 extensive beds of trona. At least 25 of these exceed 3 feet (1 meter) in thickness and most of them are more than 300 square miles in extent. Five have been exposed in mines and lie between 800 and 1500 feet below the surface. Others lie at depths of from 400 to 3500 feet. Three companies have underground mines that supply trona to adjacent soda ash plants. These are the FMC Corporation, Allied Chemical Corporation, and Stauffer Chemical Company. A fourth, Texasgulf Corporation, has a mine under development. In 1974, annual soda ash capacity in the Green River area was approximately 4,300,000 tons, which requires the mining of about 7,500,000 tons of trona.

Jan 1, 1975

By Robert E. Barrett

The history of mine safety legislation in this country is also a history of mine explosions. Nearly every piece of safety legislation that has been introduced or amended has resulted from some type of a disaster. When coal was first discovered and mined, it was extracted from along outcrops. As the coal became depleted near the surface, underground mining developed. When the first mine penetrated the outcrop, a great number of problems developed, many of which remain with us today. One of those problems is the potential for mine ignitions and explosions. Naturally, when underground mining progressed a few feet into the outcrop, some type of artificial light was needed. Early accounts of mining in Spain, Italy, Japan, and Great Britain indicate that torches served to light the mines. Later, candles were used, and still later, earthern oil lamps containing fish oil were used. As workings got deeper, explosions began to occur. When one did occur it was thought to be the work of goblins or the devil. As explosions became more frequent, it became very obvious that the use of open flames for lighting was very dangerous. A substitute was sought. Dried fish skins which gave off a weak phosphorescent light were tried. A mixture of flour and lime made from oyster shells called Canton phosphorous was also tried unsuccessfully. Fireflies in a bottle were also used.

Jan 1, 1976

By Rollien R. Wells

The Bureau of Mines was created in 1910 by an act of Congress and subsequently directed to: "...conduct inquiries and scientific and technologic investigations concerning mining, and the preparation, treatment, and utilization of mineral substances with a view to improving health conditions, and increasing safety, efficiency, economic development, and conserving resources through the prevention of waste ..." Under this broad charter, the Bureau's responsibilities have changed and grown from an almost exclusive concern with coal and coal mine safety to the present emphasis on a full spectrum of mineral producing and consuming problems. In the past 30 years, the domestic consumption of coal, oil, gas, metals, and industrial minerals has more than quadrupled, in parallel with the rapid and enormous growth in industrial production. Of the scores of metals and nonmetals essential to the Nation's progress and security, many are scarce and difficult to wrest from domestic sources. Reserves of some ores are dwindling. Available ore resources are becoming leaner and more difficult to treat. In recognition of this many faceted problem, the Bureau has engaged in a continuing quest for new and improved technology to enable economic exploitation of marginal minerals and fuels, to find substitutes for minerals in short supply, and to create better materials to meet the expanding and diverse requirements of the growing economy. The current central concern of the Bureau is focused on meeting projected fuel, metal, and mineral demands at the lowest real cost by recovery from available resources by new and improved technology that minimizes waste, hazards, and social and environmental problems.

Jan 1, 1970

By K. W. Lentz

The Maybell Mill of, Trace Elements Corporation, Unit of Union Carbide Corporation is located approximately five miles northeast of Maybell, Colorado, and twenty-five miles northwest of Craig. It is located in the midst of the uranium ore deposits whose presence, made it possible. In November 1953 Russel Cutter, Chief Geologist for the original Trace Elements Corporation, picked up high readings on a scintillometer while flying over this area. Later, with George Morehouse, Chief Engineer for the original. Trace Elements Corporation, he started a search for surface indications. In this search, they found an out crop which can be regarded as the discovery lode on this property. The actual locating of claims and acquiring free lands and state lands was begun in March 1954. During 1955 enough drilling was done to indicate that a sufficient tonnage of ore existed to make possible a mill. These ore deposits are located in the Browns Park formation which is an unconsolidated sandstone with a few hard lime ribs running through it. The geologists tell us that this region was once a vast basin which became filled with wind blown sand and volcanic tuff, Later on, ground waters brought uranium into the basin which precipitated out in the sand. During the late summer and fall of 1955, a small pilot plant was operated under the supervision of John L. Chapman testing these Browns Park ores. During the operation of the pilot plant, three small open pits were developed and the ore from these pits shipped to Union Carbide Nuclear Company, Division of Union Carbide Corporation, at Rifle. To date all ore is being mined from open ptis. In the fall of 1956 the original Trace Elements group signed a contract with: the AEC for a mill at Maybell and on November 5, 1956, Union Carbide acquired the Trace Elements Corporation properties and contract. During the next two months, intensive research was carried out on the Browns Park ores by our research lab at Rifle. They also checked some of the metallurgical results which had been obtained through the operation of the pilot plant by the original Trace Elements group. During this period, a report on Trace Elements Corporation ores was also prepared by the Colorado School of Mines Research Foundation. This report contained data on representative samples of the ore tested for the original Trace Elements group. From this research and study a flow sheet was decided upon.

Jan 1, 1959

By E. Manev

Thin aqueous equilibrium film studies and surface tension measurements on a mixed surfactant system consisting of polyethylene oxide (a model frother) and potassium ethyl xanthate (a model collector) enable the interaction between the two surfactants at the air/solution interface to be elucidated. For the film containing the non-ionic frother, the interface was charged and addition of low concentrations of xanthate acted as a common electrolyte and reduced the thickness of the film inducing rupture. However, at high xanthate collector concentrations, the negative charge xanthate was found to interact with the non-ionic and caused a build-up of negative charge at the air/solution. Higher frother concentrations were necessary to produce non-rupturing thin films upon increasing the xanthate concentration.

Jan 1, 1992

By D. J. M. Grodzian

Polymorphic transformations taking place in grinding processes, of massicot to litharge in PbO system, and of y to a in Fe203 system, were re-investigated. Grinding was carried-on in a steeel rotation mill charged with WC balls, under inert atmosphere. The kinetics of transformation in PbO was established by means of quantitative X-ray diffraction analysis. The resulting data fit a modified logistic growth function up to about 75% of transformed volume fraction, when a mixture at steady-state equilibrium is formed. The reasoning for the use of a modified logistic function is discussed. A sigmoidal growth function can be used if resulting data fit also an empirical power relationship between transformed volume fraction and time. However, it lacks the significance expressed by a modified logistic function. Assuming, the loss in magnetism is directly related to the amount of transformation in Fe 203, a quantitative analysis was performed using a magnetic balance method. The results fit only the modified logistic growth function, and transformation proceeds almost to completion. A wide literature survey of the subject is given. Available data from literature is compared with the results of the present study, and is shown also to fit a modified logistic grown function, with surprisingly similar slpes in a linear plot, independently of the material. The instrumentation effect on kinetics parameters, and the establishment of equilibrium mixture values, are discussed.

Jan 1, 1975

By Charles Dumaresq

The management of mine tailings poses a complex range of potential risks, including physical risks, such as the risk of catastrophic failure of a tailings facility and chemical risks such as the risk of long-term leaching of contaminants into the downstream environment. If these risks materialize, they can lead to a wide range of impacts on people and the environment, including human fatalities and severe impacts on downstream ecosystems, and the costs of recovery borne by industry, communities, governments, and society as a whole can be immense. Tailings facility failures in Canada (2014), Brazil (2015 and 2019), South Africa (2022), and in other locations around the world underscore how high the stakes are when mines produce and manage tailings (WISE Uranium Project 2019). Understandably, many people do not trust the mining industry to manage tailings responsibly. As an industry, it is our responsibility to manage tailings in a manner that is responsible and strives to minimize harm associated with tailings management, including effectively managing both the physical and chemical risks associated with tailings. Standards have an important role to play in responsible tailings management by setting expectations for standards of care and providing a means to measure and report on performance. In jurisdictions with strong legal requirements for tailings management, standards play a complementary role, pushing performance improvements in areas that may be difficult or impossible to address in legal requirements. In jurisdictions where legal requirements are lagging, standards may represent the de facto leading practice and may be the primary tool to help ensure responsible tailings management. Implementation of standards can help companies demonstrate that tailings are being responsibly managed and help build trust and credibility. Most importantly though, standards are important tools to help ensure that the risks associated with tailings are reduced, and that remaining risks are effectively managed. However, we must recognize that conformance with standards can have a down-side – the proverbial two-edged sword. Having standards is vital but there is a risk that implementing standards becomes a “box checking” exercise, with ongoing conformance leading to complacency. We must not allow ourselves to fall into the trap of believing that, just because we are complying with applicable standards and laws, we are therefore doing our best, and that “it can’t happen to us.” In addition, if conformance becomes the goal and the standard does not have mechanisms to drive continual improvement, then once the standard is met, there may be no incentive to improve. The point of complying with standards is not to pass the test. The point is to manage tailings responsibly, prevent catastrophic failures, and minimize harm. The point is to do better, because we must do better. To do that, we need to strive not for conformance, but for excellence in tailings management, driven by continual improvement and a quest to do better.

Feb 1, 2025

By C. M. Goodall

Solids and liquid phase residence time distribution data is reported for a laboratory column flotation cell. The effects of various physical flotation parameters on residence time distributions are reported and analyzed. A plug flow model with recycle is proposed for the froth phase and a tanks in series model for the pulp. By comparison of two and three phase residence time -distribution data it has been shown that the use of liquid residence time distribution data to predict the residence time distribution of the solids in a column is not valid.

Jan 1, 1990

By B. Bag

Saturated and unsaturated fatty acids are used in the flotation of iron values present in iron ore. Among the several fatty acids, oleic acid and its sodium salt are widely used. To substantiate the flotation results, the quantum chemical calculations of a few such acids have been carried out by adopting the semi-empirical AM1 method. These acids have been further optimized in the presence of an iron atom. The electronic interaction of the polar carboxylic head group of oleic acid with the iron atom is higher compared to the other acids. The numerical results support the flotation behavior of iron ore with oleic acid. Key words: Iron ore, Flotation, Fatty acids, Quantum chemical calculations, Semi-empirical AM1 method

Jan 1, 2009

By J. G. Groppo

Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 pm) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20 percent level moisture will be an important step in successful implementation of the advanced cleaning processes. This study is a step in the Department of Energy's program to show that ultra-clean coal could be effectively dewatered to 20 percent or lower moisture using either conventional or advanced dewatering techniques. The main focus of the pilot plant study was on proof-of-concept testing of a dewatering technique for a fine clean coal product. The coal industry is reluctant to use the advanced fine coal recovery technology due to the non-availability of an economical dewatering process.

Jan 1, 1997

By D. G. Purdy

Planning, as defined in Webster's New Collegiate Dictionary, is a detailed program of action designed to achieve an end. When developing a detailed plan to incorporate all the complex activities involved in a surface lignite mine, many elements must be carefully evaluated as to the individual and cumulative effects on the end result. The following elements are generally evaluated when planning a surface lignite mine: ? Reserve evaluation, including lignite quality characterization; ? Delineation of mining parameters, including lignite recovery factors, geotechnical factors, land control factors; ? Selection of mining blocks; ? Pit sequencing; ? Reclamation, including soil reconstruction design and land use planning; ? Overburden handling design; ? Selection of equipment; ? Sizing of equipment; ? Manpower requirements; and ? Other elements, including contract negotiations and execution, financing, investment return, operation economics, permitting and scheduling.

Jan 1, 1985

By J. J. Zaluski

The Surface Mining control and Reclamation Act (public Law 95-87) (here-inafter the "Act" or "SMCRA") passed by congress in August of 1977 represents a comprehensive federal scheme for controlling surface coal mining and the surface effects of underground mining through permitting requirements, performance guidelines, and reclamation planning. While the provisions of the Act have been the subject of numerous legal challenges and court battles over the years, it is difficult to identify a more controversial program within the Act than the provisions for designating lands as unsuitable for surface coal mining operations. The lands unsuitable designation process provides for the acceptance and review of petitions submitted by citizens or organizations seeking to have specified land areas designated unsuitable for all or certain types of surface coal mining activities. In filing these petitions, the interested parties or petitioners are required to make allegations about potential adverse impacts on people or the environment and submit evidence supporting their allegations.

Jan 1, 1992

By J. P. Baur

The sensitivity of radiochemical techniques makes possible the study of the initial stage sulfuric acid leaching kinetics of chalcopyrite and other copper sulfide minerals. High-grade Transvaal chalcopyrite was neutron irradiated in a TRIGA reactor to produce radioisotopes copper-64, iron-59, and sulfur-35. Dissolution rates were measured in the time interval zero to 60 minutes during which time significant anomalies were observed. First, an initial period of rapid dissolution lasting a few minutes; second, an arrest or "plateau" region usually lasting from 6 to 10 minutes; third, a second period of dissolution of lesser rate than the first. The effect of solution variables such as pH, oxygen partial pressure, and ferric ion concentration at different temperatures were measured. The initial rate data were correlated by considering the rapid reaction to be due to the dissolution of surface oxidation products or the formation of an iron depleted surface layer. The data for the second slower reaction have been explained to be due

Jan 1, 1972

By Stephen H. Stow

Economically important heavy minerals have been studied in the sediments of offshore Alabama and Mississippi. Sandy samples have been collected from a 200 square mile area from Dauphin to Horn Islands. The minerals concentrate in sediments under 10-35 feet of water and may reach 2.4% by weight. The distribution of total heavies is related to the hydrodynamics of offshore Alabama-Mississippi; the greatest concentrations are in the Gulf where the longshore current is diverted from its westerly flow. Preliminary observations indicate that the distribution of individual minerals can be correlated with wave energy, particle size, specific gravity, and morphology of the mineral grains. The coarser, lighter minerals--kyanite, sillimanite and staurolite--are concentrated in relatively low energy areas in the Mississippi Sound and at the end of Dauphin Island in the Gulf; maximum concentration for each is 34.5%, 6.0% and 43.2%, respectively, of the heavy minerals. The smaller, more denseminerals--ilmenite, rutile, leucoxene, zircon and monazite--are concentrated in high energy areas in the Gulf; maximum concentration for each, respectively, is 42.0%, 5.9%, 9.652, 10.7% and 1.3% of the heavy minerals. On the basis of a minimum concentration of 1% heavy minerals, two areas have been identified and the total amounts of different minerals have been calculated to a depth of 25 feet of sediment. The data are preliminary and in no way indicate recoverable reserves, but they do show that on the order of 20 million tons of heavies exist. These deposits should be termed "indicated resources".

Jan 1, 1975

By G. Deschenes, M. Fulton

The New Britannia Mine processes a qumtz-carbonate gold ore containing 4.63 git Au at a rate of 2,200 tpd. The ore contains approximately 3 .0% arsenopyrite, 2. 7% pyrite and the rest is gangue minerals. Eight to ten percent of the gold is refractory to leaching. Two years ago, New Britannia Mine experienced cyanidation problems. Gold extraction was not stable and occasionally decreased significantly. Preliminary test work, at laboratory scale and in the plant, indicated that lead nitrate addition was beneficial. A laboratory study was initiated to evaluate the level of control of the parmneters (grinding size, dissolved oxygen, pH, free cyanide and lead nitrate) to optimize the efficiency of the process. It was found that lead nitrate addition is required to alleviate the effect of metallic sulphides. This addition causes a significant increase in the gold leaching kinetics and a reduction in the cyanide consumption. The optimum system appeared to be: leaching for 24-30 hours at pH 11.8, 50 git lead nitrate, 250 ppm NaCN and 8 ppm 02. The gold extraction was 89.8% with grinding at 89%-74Fm (leached tail at 0.48 git). Cyanide and lime consumption are 0.40 kglt NaCN and 1.9 kglt respectively. Following the incorporation of lead nitrate, overall gold extraction was increased from 89.2% to 91.1 % but no change was noticed in cyanide consumption. The gross profit is $CDN 988,000 per year.

Jan 1, 1999