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By N. A. Eilertsen

Mining operations were in progress at the Shawangunk mine near Summitville, Sullivan County, N. Y. as early as 1843 and again as late as 1918. Difficulty in effecting mechanical separation of sphalerite and galena was the primary reason for abandonment by various operators. The Bureau of Mines investigated this mine by diamond drilling, sampling, and performing beneficiation tests. The investigation included the construction of 1.25 miles of access road and the completion of 6,526 feet of core drilling in 24 holes. In addition, 151 samples were taken in the mine. The investigation proved an extension of ore contiguous to the old mine workings and resulted in the discovery of another ore shoot at depth. The ore occurs as fissure filling in a fault zone and contains concentrations of zinc and lead sulfides with minor dissemination of chalcopyrite in a quartz gangue. Metallurgical tests indicate that the ore can be concentrated by selective flotation.

Jan 1, 1950

By T. E. Howard

The western phosphate field, comprising parts of Idaho, Montana, Wyoming, and Utah, contains one of the world's largest known reserves of phosphate rock. Although phosphate-rock deposits of good-grade have been known since before the turn of the century and production has been recorded since 1906, real development of this important field did not begin until immediately after World War II. Since then fertilizer-manufacturing facilities using western phosphate rock have been expanded, and three electric-furnace plants for producing elemental phosphorus have been installed, resulting in a rise in mine production from 323,955 long tons2/ in 1945 to 1,653,916 long tons3/ in 1953. Interest in the field is increasing, and it is reasonable to expect that the western phosphate industry will continue to expand. Before 1945 all western production was from underground mines. In that year the first strip mine in the field was started near Montpelier, Idaho,~ and in sub-sequent years a number of other open-pit mines were opened in southeast Idaho and western Wyoming. At present the major part of the production comes from surface mines. Underground mining has continued, and new underground mines have been opened in the field, but recent exploration by operating companies has been aimed primarily at developing additional deposits suitable for low-cost surface mining. Preliminary reserve estimates by the Federal Geological Survey5/ indicate that only a very small part of the total resource may be recovered by surface methods and that the industry eventually must depend largely on underground mining. Because one function of the Bureau of Mines is promoting the conservation and development of the Nation's mineral resources, it is appropriate that research be conducted to develop low-cost maximum-recovery underground mining methods applicable to western phosphate-rock deposits.

Jan 1, 1956

The Bureau of Mines studied available information on the nature and occurrence of potential sources of aluminum in the United States, its Pacific island possessions, and Puerto Rico to obtain data for use in evaluating the production capability and costs of extracting the aluminum from such materials. The quantity, type, and grade of the materials range from 4 billion tons of bauxite, bauxitic clay, and kaolin averaging 33 to 42 percent Al2O3 to nearly 600 billion tons of anorthosite containing only 27 percent Al2O3. Principal deposits of bauxite, bauxitic clay, and kaolin occur in Arkansas, Georgia, Hawaii, and Oregon. Major anorthosite deposits are located in New York, Wyoming, California, Idaho, and Montana. About 11 billion tons of material in deposits of various types of clay, the kyanite group of minerals, laterites, and shales averaging 27 to 30 percent Al2O3 comprise additional resource's from which aluminum some day may be extracted. Material meeting specifications of the study was found in only 22 States and the Pacific island possessions. Utilization of these large low-grade sources of aluminum awaits development of processes that are economically competitive with the Bayer process for extracting alumina from baxuite, which is at present the only commercial ore of aluminum. Changes in economic and political conditions also may play important roles in the eventual development of the potential sources of aluminum.

Jan 1, 1967

By Tom Setterfield

Conclusions ?Canada is a prospective place to explore for IOCG deposits ?Time distribution of IOCG mineralization in Canada mimics that in the rest of the world ?Canada may have been the first country to start mining IOCG deposits ?Production from newly discovered IOCG deposits in Canada may start soon

May 1, 2006

By A. H. Shoemaker

This paper describing the mining practices at the Old Dominion mine, Globe, Ariz., is one of a series being prepared by the United States Bureau of Mines on mining practices, methods, and costs in the various minim districts in the United States. The Old Dominion mine is situated in the eastern port of the Globe-Miami district, about 1-1/2 miles north from the center of the town of Globe. An average of nearly: 1,200 tons per day was mined during 1928. The prevent production is about 1,500 tons per day; of this amount,, approximately 100 tons is direct-smelting ore that is shipped to the smelter at Miami and 1,400 tons milling ore which is treated in the company?s concentrator at Globe. About 600 men are employed at the mine.

Jan 1, 1930

By Pengfu Tan

A thermo-chemical model of the copper P-S converter and a viscosity model for the converter slag have been developed to predict the behavior of magnetite in the converter slag, amounts of slag and matte, compositions of slag and matte, volume of the bath, bath temperature, slag blow endpoint determination, SEMTECH OPC signals, and the viscosity of converter slags. The predictions of bath temperature, slag and matte compositions, and magnetite content in the slag have been validated by the industrial data. The effects of fluxing strategy, returns and skim charges, oxygen enrichment, and temperature on the magnetite formation in the slag have been predicted and discussed. The effect of oxygen potential, SiO2/Fe in slag, detection of slag blow endpoint, and temperature on Fe3O4 content in converter slag, slag viscosity, liquidus temperature of converter slag and skimming operation has been modeled and discussed as well. Some applications of the industrial operations have been presented.

Jan 1, 2009

By Andrew St. Amant

This report reviews the first three "investigative and concept generation" phases of the referenced contract, and details task performance of Phase IV. This last phase integrated the most promising concepts from Phases I, II, and III into a prototype detailed design which was manufactured, and then tested on a mine locomotive. The concepts developed during the first three phases provided "Improved Pole Tracking," automatic "Rapid Pole Retraction" in the event of dewirement, and servo-operated "Remote Pole Repositioning" on the trolley wire. The Appendix of this report supplies detailed information for the design and construction of the prototype system which is comprised of an RCB (Remotely Controlled Base subassembly), an RCL (Remote Control Lever subassembly) and an SAU (Servo Amplifier Unit) subassembly.

Jan 1, 1980

By Henderson, Robert

A GOOD idea of the magnitude of the underground operations at Climax can be gained from the following figures. A little more than 43,000,000 tons has been drawn from the mine and of this amount, 40,500,000 tons has been drawn in the past ten years and 12,000,000 tons was drawn in two of the war years. The maximum daily average output over a period of one month was slightly more than 20,000 tons but during this period, production on certain days was 24,000 tons, and 9000 tons was produced in a single eight-hour shift. This production came chiefly from 260 draw points although all of them were never in operation at one time. The haulage system for these draw points is made up of 7.5 miles of 36-in.-gauge track, and 131,000 ft. of subsidiary drifts and 44,000 ft. of raises have been driven to develop the necessary broken ore reserves for this high production. Power consumption is often considered an index of operating efficiency. In 1943, the year of maximum production, the mine power consumption was 19,223,000 kw.-hr. or 3 kw.-hr. per ton; in 1945 it was 3.5 kw.-hr. per ton. To handle this amount of power, there are four transformer stations and one switch station in the mine. Mr. Garrabrant, the chief electrician, describes the electrical installation in this issue.

Jan 1, 1946

By T Trott, M Lewis, G Lumley

The analysis of equipment trends in The AusIMMÆs revision of Monograph 19 - Australasian Mining and Metallurgical Operating Practices (AMMOP) (in prep) in the paper by Graham Lumley raised some interesting, and in parts disturbing, trends in the Australian open cut mining industry. According to the Australian Bureau of Statistics (2011) the productivity of the whole mining industry is down by 34 per cent since 2001. In terms of open cut equipment, median output for draglines is down by 15 per cent since 2003, electric rope shovels are down by 41 per cent since 2003, hydraulic excavators are down by 39 per cent since 2008, front-end loaders are down by 39 per cent since 2007 and trucks are down by 41 per cent since 2006. Clearly e boom has not been good for the efficiency of the mines. During this same time, best practice (defined as the average of the top ten per cent by annual output per unit of input) has declined, but not by as much as the median (eg shovels down by eight per cent, excavators down by 19 per cent and FELs down by five per cent). This paper will build on the analysis of AMMOP to understand the differences occurring between median and best practice and identify the factors contributing to the decline in performance. As the industry enters a period of potentially lower prices for commodities and reduced margins, pressure will be brought to bear on mine sites to start moving more with the equipment they have. An understanding of where efficiency has been lost will be a key component in that. The information contained in AMMOP, and the subsequent analysis of that information in papers such as this one, will be crucial to reversing the decline in open cut equipment performance.CITATION:Lumley, G, Trott, T and Lewis, M, 2012. Reversing the trend in open pit mining equipment output, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 75-82 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By Ramana G. Reddy, M. R. Bogala

Transition metal silicides have good potential for converting waste heat into electrical energy at higher temperatures. Transition metal silicides are used as thermoelectric alloys at higher temperatures because of their low toxicity, high natural abundance, good transport properties, and better thermal stabilities. In this article, thermodynamic, and thermoelectric properties of promising metal silicides are reviewed, calculated, and compared for waste heat recovery application. Higher manganese silicide (Mn4Si7) was produced from easy one-step self-propagating high-temperature synthesis (SHS) procedure of arc-melting technique. Characterization of the alloy phases were done using X-ray diffraction (XRD). In this study, lattice constants, Vickers microindentation hardness, and thermoelectric (TE) properties (Seebeck coefficient, electrical conductivity, thermal conductivity, and figure of merit) of Mn4Si7 alloy were experimentally determined, and compared with the reported literature values.

Mar 1, 2017

By V. Rajaram

Rock reinforcement systems are used in open pit and underground mines to stabilize the rock mass in-situ and provide safe working conditions. Significant progress has been made to date in the design and implementation of rock reinforcement systems to accommodate bad rock conditions and larger excavations. However, the rationale for the design of rock reinforcement systems remains essentially the same and can be categorized into three groups, namely 1. to create a beam of competent rock in stratified formations, 2. to resist sliding motion in jointed rock, 3. to passively support the superincumbent loads in highly stressed ground. Case histories of the rock reinforcement sys¬tems that illustrate these design approaches will be presented in this paper.

Jan 1, 1983

By Mario Teruo Enju

Soluções flexíveis, com baixo custo de implantação e manutenção, de sistemas de controle de processos e informação utilizando tecnologias de ponta desenvolvidas em plataforma .Net Framework. Focadas inicialmente em área Metalúrgica, onde eficiência em custos e alta confiabilidade tem relevância fundamental para sua viabilização econômica, estas soluções podem também ser aplicadas em áreas Siderúrgica, Petroquímica e demais segmentos. Integração das informações do chão de fábrica com o sistema de gestão da empresa com objetivo de facilitar a tomada de decisões estratégicas. Banco de dados relacional é o principal repositório de dados para compartilhar informações com a rede corporativa, gerenciado por uma ferramenta de software em tempo real para as lógicas de negócios e camada de apresentação. Maior performance, facilidade de operação, disponibilidade de dados, OEE, manutenção simplificada, acesso e ações remotas são viabilizados, permitindo menor custo e maior eficiência.

Jul 30, 2018

By Karl E. Starch

This Bureau of Mines report is a background study of severance taxes on mineral production. The rates, bases, and other features of State severance tax legislation as of March 1978 are presented, as are the amounts of State severance tax collections for fiscal year 1977, Some statistical comparisons between severance tax collections, total State tax collections, and total value of mineral production in the States involved are presented to portray the relative importance of severance taxes both in State tax revenue systems and in mineral industry revenues. A general discussion of the purposes and principles of taxation, the unique nature of a mining enterprise, the various types of taxes imposed on mineral production, and the character and rationale of the severance tax and its impacts on mining firms sets the severance tax in perspective. A bibliography of materials on the severance tax is included.

Jan 1, 1979

By Ying Gu

Automated mineralogy methods and tools, such as the Mineral Liberation Analyzer (MLA) and the QEMSCAN, are now widely used for ore characterization, process design and optimization. Several case studies published recently demonstrate that large gains can be obtained through grinding and flotation optimization guided by automated mineralogy data. However, since automated mineralogy can only provide the information pointing to where the process gains can be made, it does not directly impact the production gain. Thus, a question is often asked: how to value the contribution of automated mineralogy to process improvement of a particular plant. This appears to be a difficult question. On close examination however, it is found that this is essentially a question of the value of information and it is reasonably well documented in various other industries. Hubbard (2010), in chapter 7 ?Measuring the Value of Information?, dealt with exactly this type of problem. The value of information is the reduced risk of an investment and opportunity loss. The methods Hubbard developed can be applied to estimate the value of automated mineralogy, as well as metallurgical test work, which also produces information that reduces the risk of investment. This paper first introduces Hubbard?s theory on the value of information and how to measure it. It then applies his methods to estimate the value of automated mineralogy, using Anglo Platinum?s fine grinding project as an example. In this case, the value of automated mineralogy includes the reduction in investment risk worth US$ 62.5million, in project rejection worth US$197 million and in opportunity loss worth US$320 million. In the end, a general model is developed to allow the simulation of the value of automated mineralogy in different mining operations constrained by different parameters.

Sep 1, 2012

By Samuel S. Wyer

THE installation of the gas-producer power-plant in America has been so unusual that all engineers have viewed it with in¬terest; a large majority, however, regard it with a lack of con-fidence and many with positive distrust. Despite the fact that European engineers have usually been less inclined to take the initiative along experimental lines than are Americans, they have, nevertheless, developed the gas-producer plant to a very high state of efficiency to which they were forced by the neces¬sity of economy in fuel-consumption. The gas-producer power-plant is so common in Europe that engineers as well as the general public regard it with the same degree of confidence that is now universally placed in steam¬plants. Gas-engines, both small and large, are in general use there, and central stations, aggregating several thousand horse¬power, are quite numerous. The fact that gas-producer power-plants have received so little attention in America may be attributed to five conditions:-1', ignorance and prejudice; 2, newness of work; 3, in-

Mar 1, 1905

By Jr. Boyle

This report analyzes the availability of chromium in the form of ferroalloy products (high-carbon and low-carbon ferrochromium and ferrochromium-silicon) and chromite products (metallurgical, chemical, refractory, and foundry sands) in market economy countries (MEC's). A total of 873.5 Mmt of in situ material, containing 202.5 Mmt of chromium, in 10 MEC countries was analyzed for availability as of the January 1989 study date. Extraction and beneficiation of this in situ material would result in 475.4 Mmt of marketable chromite products. As analyzed, 288.5 Mmt of these chromite products would be available for export or for internal chemical and refractory use and 186.9 Mmt would be smelted in-country to produce 74.3 Mmt of high-carbon ferrochromium, 3.9 Mmt of low-carbon ferrochromium, and 2.0 Mmt of ferrochromium-silicon, all available for export. A network flow model, which includes centrally planned economy countries (CPEC's), was also constructed to analyze world chromium supply and demand interactions for the period 1986 through 1994 and to address a hypothetical North American embargo on direct imports of all South African chromium products beginning in mid-1990. The model shows capacity constraints developing in the MEC high-carbon ferro chromium industry in 1987 and a possible subsequent overreaction by the industry in terms of new capacity additions. The results suggest that sufficient chromium is available to North America should an embargo on direct imports from South Africa be imposed by its governments. However, the effect on export revenues in South Africa is relatively small, and timely increases to world ferrochromium, chemical chromite, and foundry sand chromite capacities would be required.

Jan 1, 1993

By R. K. Sinha, B. S. Choudhary, Desh Deepak, A. K. Mishra, Hemant Agrawal, Shankar Kumar

Despite several methods (empirical, statistical and machine-learning tools) to calculate blast-induced ground vibration, it is not easy to predict and simulate blast vibration precisely under varying blasting loads and strata conditions due to complications in the blasting procedure. In this study, field blast data were simulated in Ansys software using explicit dynamics, and ground vibrations for 20 single-hole blasts were monitored. The densities of emulsion explosives were in the range of 0.9 to 1.15 g/cm3. In the laboratory, rock properties were determined from rock samples collected from the mine site before blasting. The in-hole velocity of detonation (VoD) and density of the emulsion explosive were also determined and used in numerical analysis to know the ground vibrations at specific points. The results of ground vibrations predicted by the model were validated using field data.

By Stanley J. LeFond

Brazil is one of the most outstanding examples of economic development of our time. Its amazing growth record is substantiated by a GNP which has increased at an average rate of 92% for the period 1968-1970 and estimates for 1971 range from 11.7-12.5%. Hence, this growth, coupled with a more relaxed attitude of the Brazilian government towards foreign participation in business opportunities and the remittance of profits out of the country, has caused many exploration companies to reevaluate the potential of Brazil. Despite recent press notices and publicity, Brazil is still not a mining country in the tradition of Canada or Australia. It is still basically an agriculture and manufacturing country.

Jan 11, 1973

By Deniz Akbay

The strength of rocks and soil is a crucial design parameter in engineering projects, and it can be determined through various test methods such as uniaxial compressive strength, tensile strength, and shear strength. The point load index test is a popular indirect test method for predicting the uniaxial compressive strength of rocks. However, the reliability of the point load index’s estimation of uniaxial compressive strength of rocks is questioned due to the wide range of coefficients that are used to predict uniaxial compressive strength of rocks using point load index values. Factors such as the shape and type of rock specimen, practitioner, and test apparatus used can affect the accuracy of the point load index test. This study investigated the effect of four different specimen shapes used in point load index test (diametral, axial, block, and irregular lump tests) in predicting the uniaxial compressive strength. The rock samples were tested using four test procedures which are called diametral, axial, block, and irregular lump tests. The results showed that the irregular lump test was the most accurate in predicting uniaxial compressive strength, with the highest correlation coefficients and lowest mean absolute percentage errors. The point load index test can be used as a reliable predictor of uniaxial compressive strength of rocks when the irregular lump test is preferred.

Oct 18, 2023

By Wei Sun, Xiangsong Meng, Xiaodong Li, Weisheng Huang, Yuehua Hu, Chonggao Cao, Haisheng Han, Wensheng Chen, Runqing Liu, Central South University

"The similar flotability of scheelite, fluorite, and calcite resulted in the difficult separation by flotation. This work revealed the effect of water glass on the flotation of scheelite by FTIR and the wettability change of the usual cleavage plane, and proved that water glass inevitably influenced the flotation of tungsten minerals to a large extend in traditional fatty acid flotation process. A new collector, benzohydroxamic acid complexes, was found to be selective for the separation of scheelite and calcium minerals with little water glass. Hence a novel flotation process was developed for the recovery of tungsten minerals in shizhuyuan mine in China. Normal temperature flotation of tungsten minerals was developed to instead of the classical “Petrov's process” for scheelite-calcite-fluorite type ores. Compared with the traditional process, the recovery was improved by 10% and the grade of scheelite concentrate was above 55%. The disappearance or decreasing of water glass contributed to improving the recovery of tungsten and fluorite and the circulation of water and reagents.INTRODUCTIONChina is rich in tungsten resources and the proved reserves accounted for 60% of the world's reserves (Cai Gaipin et al., 2009). However the wolframite has been dried up and the scheelite resource has become the main resource of the tungsten metal. Scheelite deposits were classified to scheelite-silicate type and scheelite-calcite-fluorite type based on the associated gangue minerals. Scheelite was easy to separate from the silicate minerals. Flotation separation of scheelite from calcium minerals creates difficulties because of the existence of the same cation in the minerals and similar physicochemical characteristics such as solubility, hardness, specific gravity, PZC (point of zero charge) etc.(Arnold & Warren, 1974; Yongxin & Changgen, 1983; Ozcan & Bulutcu, 1993a; Deng et al., 2015, 2016;). The conventional collectors used in the flotation of scheelite ores are generally fatty acids or fatty acid derivatives ( Yongxin & Changgen, 1983; Oliveira & Sampaio, 1988; Sivamohan, 1988; Shi et al., 2014; Bo et al., 2015). It is difficult to separate scheelite especially from calcite with these reagents because the adsorption mechanism of these collectors occurs through chemisorption of the oleate ion onto the mineral surface (Atademir et al., 1979; Changgen and Yongxin, 1983; Hiçyìlmaz et al., 1993; Hu et al., 2011). Therefore, it is almost impossible to separate them by fatty acid flotation without using any selective depressant. Although oleoyl sarcosine was used as a selective collector in the flotation of fluorite and siliceous scheelite ores (Ozcan & Bulutcu, 1993b; Ozcan et al., 1994), this selectivity is not adequate for a low-grade calcitic scheelite ore. Unfortunately, the reagents such as organic colloids (dextrine, starch), quebracho, sodium phosphates, sodium silicate solutions containing polyvalent cations (hydrosols), etc. (Yongxin and Changgen, 1983; Schubert et al., 1990; Shi et al., 2014; Bo et al., 2015) used for calcite depression also depress scheelite to a large extent."

Jan 1, 2016