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By John Cline

The economic value of calcium carbonate when used as an extender or filler basically falls into two categories: 1. Lessening the cost of the final product to which it is added. 2. Contributing desirable physicals to the final product. In most instances, a combination of these two may be achieved. The mineral limestone which is found in abundant quantities in many areas of the world is the source of 99% (+) of the calcium carbonate used as fillers and extenders. Precipitated, or chemically formed, calcium carbonate is also available, but by comparison, in very limited quantities.

Jan 1, 1985

By W. R. Ernst

A method for the removal of nickel and vanadium contaminants from spent HDS catalysts involves pretreating the catalyst with H2S followed by the extraction of the metals with an acidic solution of ferric ion. The ferric ion solution alone removes significant amounts of active ingredients cobalt and molybdenum; however, after pretreating the catalyst with H2S, the extraction becomes more selective for the removal of Ni and V.

Jan 1, 1986

By R. M. Hays

Jan 1, 1980

By W. Rocher

The Minera Ojos Del Salado (?MINOSAL?) concentrator is located 20 kilometers southeast of Copiapo, Chile and processes copper ore provided by its Santos and Resguardo mines at a capacity of 4,200 tip (4,620 stpd). Phelps Dodge acquired the majority interest in MINOSAL in 1982. The principal incentive for this purchase was the exploration potential of the property. At that time, the concentrator plant was a small, antiquated installation with a capacity of 674 t/d (740 stpd). In 1982, the majority of the ore was produced from the Santos and Resguardo mines, but custom ores of copper, silver, and gold were also treated. The acquisition occurred at a crucial time in the copper business, since the price had fallen to nearly $0.50 per pound. In 1985, Phelps Dodge purchased the outstanding interest in MINOSAL and acquired 100% of the property. Today, after numerous improvements and two expansion projects, the concentrator is an interesting combination of old and new equipment. The regrind mills, for example, have been in service for about 50 years, while the ceramic concentrate filter represents the latest technology.

Jan 1, 1993

By Joe B. Rosenbaum

Waste solutions from sea water desalination processes are enriched in minerals by a factor of two or three. This suggests that extraction of selected mineral components from the concentrated brine might help pay desalination costs. The possible recovery of gold has received particular mention. Sonstadt, in 1872, reported the gold content of sea water as 65,000 micrograms per cubic meter, or 65,000 parts per trillion. At $35 an ounce, this is equivalent to $0.065 per ton of sea water. Fritz Haber, however, after his abortive venture to restore Post War I Germany to economic health by recovering gold from the sea, concluded the gold content was 4 micrograms per cubic meter. Haber's analysis is equivalent to 0.0004 cent per ton. In the past 10 years, investigators using advanced analytical techniques reported from 4 to 27 micrograms per cubic meter. Our brief experiments to determine a threshhold value for the gold in sea water employed solvent extraction for initial concentration, evaporation of the gold-loaded organic for further concentration, and atomic absorption analysis of the gold in the concentrated organic. Radioactive gold was used as a tracer for monitoring the gold through the concentration and analytical steps. Our method established that sea water contains about 11 parts gold per trillion parts sea water, or 0.001 cent worth per ton. This agrees closely with results of recent studies by other investigators employing ion exchange resins and neutron activation techniques.

Jan 1, 1969

By W. F. Mullen

Within the scope of this discussion, artificial dimension stone is defined as any manufactured product used as a substitute for natural dimension stone. The history of the development of these substitute materials is reviewed briefly, representative characteristics of each product are listed, several analyses of their market position are presented, and suggestions are made for recapturing markets lost to these products and preventing additional inroads.

Jan 1, 1959

By José Luis Lee Moreno

This paper presents a preliminary phase of a study being conducted by the Department of Geochemistry of the Consejo de Recursos Naturales No Renovables in the vicinity of the Pachuca-Real del Monte Mining District. This district is located in central Mexico, about 100 km northeast of Mexico City. It has been in operation for the past 450 years and has produced about 38 million kg of silver and about 190 thousand kg of gold. At the present it is being worked by the state owned mining company of Real del Monte and Pachuca. The rocks of the area consist mainly of Tertiary volcanics, ranging in age from early Oligocene to late Pliocene. Ore bodies are recognized as epithermal, vein type fracture fillings. The main ore minerals are argentite and acanthite normally accompanied by base metal sulphides, Gold is present in small amounts as native gold and in other minerals. Orientation geochemical studies performed on soil and rocks over known veins in the district, showed zinc to be the best indicator. Lead and silver anomalies are restricted to the immediate vicinity of the veins, mercury shows the mineralized structures only when the "C" horizon is sampled, while antimony gave erratic values. The El Chico area is about 10 km north of the Pachuca-Real del Monte district and covers approximately 400 sq km. Geological evidence indicated the possibility of an extension of the Pachuca ore bodies in this area. Results obtained from soil and rock samples from El Chico, showed several anomalous area. Detailed investigations proved these anomalies to be related to faults and fractures which in several cases have been found to be mineralized. Drilling is planned with preliminary results expected by late 1974.

Jan 1, 1974

By Donald D. Born

Mine No. 95 is located in Harrison County about 5 miles west of Shinnston, WV, with coal properties covering the northwest corner of Harrison County and the southwest corner of Marion County and with adequate Pittsburgh seam reserves to support the mine for many years. The mine was opened in 1967 and was planned, projected and operated as a room and pillar mine. It is located on a spur branch of the Baltimore and Ohio Railroad, has rail loading facilities and shipped by rail during its development stage. In 1972 it was converted to a mine mouth power station supplier and now transports coal by conveyor belt directly to the Harrison Power Station of Allegheny Power System. In 1971 the first longwall unit was installed in a selected area of the mine and immediately an orderly system of planning was developed to overcome the restrictions associated with longwall mining. The first was the development of the technique necessary for the plugging of abandoned oil and gas wells that existed in the area. With the assistance of the Morgan- town Energy Research Center of the Bureau of Mines, this restriction was overcome and thus opened a great potential for longwall mining in northern West Virginia. Other restrictions that had to be considered for longwall planning were dwellings and other improvements, snap top zones, water courses, and adequate bleeder systems, and the handling and treatment of mine drainage. In 1975 the second longwall unit was installed and soon therefore became a total longwall mine.

Jan 1, 1986

By J. Engesser

This paper discusses the effect that water chemistry, and water treatment have on pre-fired pellet quality and bentonite-binding effectiveness. A discussion concerning the effect that water temperature, water chemistry, water treatment, and surface area have on disc filter productivity and filter cake moisture is also included. This report is a summary of the data that were presented in five previous research reports, which are listed as references in this paper.

Jan 1, 2003

By J. Fuller, L. Marsden

Windborne dust from alkaline salt flats and mining-related tailings ponds is especially prone to threaten applicable ambient air quality standards. Sodium carbonate crystals, typically present, weather to an exceedingly fine, non-cohesive dust, causing air quality problems for miles downwind. Recently developed specialized polymers react with alkaline dust to form sturdy, wind-resistant crusts with good longevity. An on-going demonstration project at a major trona facility has developed techniques for cost-effective application of these polymers over large areas of soft tailings or sediments in a wide variety of situations. Recently treated areas on the order of 80 acres show effective suppression of dust.

Jan 1, 2004

By Bruce F. Bohor

Silica sand has been mined in Illinois from the St. Peter Sandstone since the turn of the century, especially in the area around Ottawa on the Illinois River in the north-central part of the state. Production of this sand, consumed mainly by the glass and foundry industries but also sought after for many other uses, has grown with the economy, and last year's output in Illinois exceeded 4,000,000 tons. Such an important commodity was given the early attention of the Illinois State Geological Survey, and a very complete report was issued in 1928, authored by J. E. Lamar. The mining and processing of the sand has changed very little during the intervening 40 years, so that much of Lamar's data and descriptions are applicable today. More recently, the stratigraphy of the St. Peter Sandstone in north-central Illinois has become better known from the work of Willman and Payne (1942). The present authors have borrowed generously from Lamar's publication, and we wish to acknowledge the contribution of both of these studies to our work.

Jan 1, 1969

By D. An, J. Withers

A nano-scale investigation has been carried out by applying an AFM (atomic force microscope) to study in situ the adsorption of various collectors, i.e., oleic acid, octanohydroxamic acid (HA), and salicylhydroxamic acid (SHA), on bastnaesite in aqueous solutions. The obtained AFM images show that the surface morphology of bastnaesite changes greatly after it contacts the solutions of the collectors, suggesting that all these collectors can effectively adsorb on bastnaesite. Increasing temperature can help increase the adsorption of oleic acid on bastnaesite. FTIR (Fourier transform infrared) results also show that all these collectors adsorb strongly on bastnaesite with a strong absorbance spectra being detected, which confirms with the results obtained with AFM imaging analysis. In general, hydroxamic acid collector (HA and SHA) adsorbs on bastnaesite mainly in the form of insoluble metal hydroxamate. This specific adsorption mechanism explains that a high selectivity with a moderate collectivity will be achieved with a hydroxamic acid collector for the flotation of bastnaesite. INTRODUCTION Rare earth metals, which are very important to modern industry, are generally extracted from numerous rare earth minerals. In practice, however, the actual extraction of rare earth is mainly from bastnaesite, monazite and xenotime. The Mountain Pass mine is one of the largest rare earth mine in the world, at which the main rare earth mineral is bastnaesite. In the past years, froth flotation has been applied to the beneficiation of Mountain Pass ore. In practice, the rare earth ore is usually crushed, milled and further separated from calcite, barite and other gangue minerals by froth flotation, in which the rare earth oxide-bearing minerals stick to aerated bubbles in the pulp and float to the surface, leaving the gangue at the bottom of the flotation cell and disposed of as tailings.(Bulatovic, 2010) In spite of the fact that froth flotation has been applied to treat the bastnaesite ore at the Mountain Pass mine, the rare earth oxide (REO) recovery is still low,(Anderson, 2015) especially compared to the one obtained with sulfide flotation. For example, the typical recovery obtained at the Mountain Pass mine was only about 70%. This may be due to the low selectivity of the collector (oleic acid). In addition, to enhance the flotation selectivity, the pulp in the mine circuit has to be heated up to 70 to 90°C and it involves a lot of energy consumption. Last but not the least, a lot of depressants have to be added to improve the selectivity of flotation process. Therefore, it is critical to re-examine the existing flotation process at the Mountain Pass mine and seek any chance of improvement. (Anderson, 2015)

Jan 1, 2019

By Jasper D. Ward

The Indiana Limestone Company has developed an insulated, thin and comparatively light-weight pane 1 suitable for use as a spandrel panel in a curtain wall. The panel is about four inches thick and is composed of limestone backed with insulation. The inner surface of the insulation is protected with asbestos-cement board or a metal pan, depending on the type of insulation, building-code requirements and appearance (if the surface is left exposed). The limestone is cut to the size of the spandrel openings and the insulation and backup is applied in the mill ready to be shipped and in- stalled in the wall grid, A mortarless and waterproof joint with the metal frame components is achieved through the use of neoprene, thiokol, and caulking, The limestone is "dirt-proofed" (waterproofed) in the mill to slow down discoloration. The panel weighs more than some presently used materials. However, ILCO's architects and engineers have found that curtain wall systems capable of withstanding imposed wind loads are made up of sections large enough to carry this extra load of stone with little or no modification to the size of the metal frame. Limestone, a traditionally sound material, can be used in this new way without losing any of its natural qualities of dimensional stability, resistance to fire, and permanence.

Jan 1, 1959

By M. F. Dibble

The Fosfago phosphate rock concentrator is located in the state of Goias, Brazil, 300 km south of Brasilia. The ore is from an enriched carbonatite, which was discovered in 1971 during exploration for pyrochlore niobium ore. The flowsheet was developed in Brazil by personnel from Agrico Chemical Company and Consolidated South America. Engineering was provided by Codemin, a subsidiary of Consolidated, Engineering and construction management was pro- vided by both Agrico and Consolidated personnel who formed the Fosfago team. The concentrator was designed for 500,000 tpy of 37-38% P2Oj dried product. The facilities consist of open pit mining, crushing, stockpiling, and concentration. The product is pipelined seven km to a filtering, flash drying, and railroad loadout station. The plant was successfully started in May 1979.

Jan 1, 1980

By J. T. Crawford

The purpose of this paper is two fold. It will: (1) examine leasing analysis as a project evaluation criterion, and (2) compare the cost of leasing with other methods of financing. The use of leasing has grown extensively in recent years as a method of obtaining equipment. The computer industry has been highly dependent upon leasing from its earliest days to dispurse its equipment to the customer, while airlines and railroads acquire large segments of their aircraft and rolling stock by leasing. Over the last few years the mining industry has leased haulage trucks, bulldozers and other equipment of similar nature.

Jan 1, 1974

By Samuel M. Brock

Problems related to strip and auger coal mining have grown with the development of the industry and the economy. New technology has produced equipment that has made mining by surface methods not only highly productive, but potentially highly destructive of water resources and natural environments. On the other hand, growth of the economy has produced an increased demand for clean water, and created new demands for amenity values that natural environments provide. Thus, opposing forces have created conflicts in resource use. And these conflicts have made surface mining highly controversial. Resolving the controversy will require the solving of complex economic and social problems. The essence of the economic problem created by surface mining is that, in the absence of proper regulation, substantial costs resulting from the process are borne by the public rather than the mine operator.

Jan 1, 1968

By J. A. Boyle

In the Frick District of U, So Steel Corporation, we have had more than 37 years of experience in the use of multiple-fan ventilation systems, in our coal mines. In our Colonial field, with a long belt installation, we have mined 85 million tons of coal with the use of the multiple fan system of ventilation. In our Palmer field, with the use of the same arrangement, we have mined 90 million tons of coal--a total of 175 million tons without one accident attributable to improper mine ventilation. The same system, fundamentally, has been installed in our expanding Robena operations and at its present stage of development we are using eight fans to ventilate this area. To date we have mined 55 million tons of coal with very encouraging results and again without any accidents attributable to ventilation.

Jan 1, 1961

By A. G. Kim

Increasing transportation costs, clean air regulations and the decreasing availability of landfill space are factors in the increased interest in the utilization of low cost disposal sites for coal combustion residues (CCR). Inactive surface and underground coal mines can satisfy the conditions for stable CCR disposal sites, and subsurface CCR injection can be beneficial in reducing the amount of acid mine drainage (AMD) often produced at such sites. The material is expected to add alkalinity to the subsurface environment and to decrease the permeability and porosity of the buried spoil. Both mechanisms can reduce the amount of acid normally generated at a mine site. The Bureau of Mines is cooperating with an independent coal company in a test of subsurface injection of a mixture of fly ash, from conventional power plants or from fluidized bed combustion (FBC) , with AMD sludge into a reclaimed surface mine. Changes in water quality parameters and the concentration of heavy metals in water samples from wells and seeps are being used to assess the effect of CCR injection. The preliminary results discussed here indicate that improvement in subsurface water quality was related to fly ash injection and that components of the fly ash were stable in the acid environment.

Jan 1, 1994

By Armine F. Banfield

Selection of a plant site is becoming increasingly more difficult and important, mainly due to advances in technology, antipollution laws and changing economic, social and community conditions. Discussion falls naturally under three headings: economic considerations, terrain considerations and environmental considerations. Aside from acquisition of surface rights, problems having to do with terrain, or topography, usually can be dealt with by management alone. Economic considerations largely involve decision-making by management plus negotiations with government regulatory agencies acting under set rules. Environmental considerations, such as air and water pollution, townsites, housing, schools, noise abatement, appearance, surface rehabilitation and the like usually are under the control of federal, state or municipal bodies with a large degree of decision-making. Successful solution of environmental problems often requires lengthy negotiations, during which public relations by the mining company play an important part. Existing union regulations or customs may confine decision- making and the establishment of wage rates, working conditions and regulations. These usually require considerable planning and negotiation. Initial production often is delayed by formal negotiations involving environmental considerations. Surface facilities usually can be divided into two broad categories: those for concentrating ores--such as gold, silver, base metals, low-grade iron ore and potash-which should be close to the mine to reduce ore-transportation costs to a minimum, and those where the ore is shipped elsewhere for treatment, such as direct-shipping iron ores, complex high-value ores requiring specialized treatment and ores from which special products are derived for local markets. The long-term aspects of plant-site selection too often are given no or insufficient consideration because of immediate financial limitations. As a result, additional capital expenditures may be required later for relocation of townsites, roads, railroads and plants to provide additional room for extension of open-pit operations, tailings disposal, storage, or danger to foundations through underground subsidence or open-pit mining. In the past, hillside sites for concentrating plants were preferred to take advantage of gravity-feed methods The modern trend, however, is to place as much equipment as possible on approximately the same level. Some costs relating to plant sites are included in this section. They are ranges as of the year 1970, and are offered only as general guides. Such costs will vary widely with geographical location and, of course, are subject to escalation due to increases in wage rates and cost of materials. Items in the bibliography contain more detailed and comprehensive data on specific subjects. Most contain bibliographies of their own.

Jan 1, 1973

By C. Cigna, M. Patrucco, D. Savoca, E. Lovera

The paper deals with the activity program and the preliminary results of a research work commissioned by IReR Research Centre and Regione Lombardia to the Department of Land, Environment and Geotechnologies of Politecnico di Torino. The aim is to define measurement, analysis and control criteria for the emission of chemical and physical pollutants from non-metal mining industries, with particular reference to noise and airborne particulates. Such emissions are related to health risks and annoyance problems, both for the working crews and the neighbouring population, and so, in order to get an effective sustainability of the industry, suitable reduction methods and assessment tools are required. A simple technique for the evaluation and forecasting of both the emission levels and deriving impact has been tested at different mining and quarrying sites, considering their differences in terms of layout and exploitation method, the latter ascribed to a series of main typologies as present in Lombardia region.

Jan 1, 2005