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By R. Duncan Gardner

This paper describing the mining practice at the Harmony mine, Baker, daho, is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts in the United States. About 150 tons of copper ore containing 4 per cent copper, 0.001 ounce gold, and 0.1 ounce silver, is being produced daily from the Harmony mine by the shrinkage method of mining. The ore is taken by an aerial tramway 1/3 mile long to the mill, where it is concentrated. The concentrate is shipped 8 miles by truck to the railroad and thence by rail to Utah for smelting.

Jan 1, 1930

By Richard H. Johnson

White Pine Copper Company began operating a plant designed to recover copper matte particles from its discarded reverberatory furnace slags in April, 1972. Seasonal operation, generally the months of April through November, continued through October, 1974, shutting down due to feed exhaustion. White Pine reverberatory furnace slags contained economically recoverable amounts of copper for a variety of reasons. Among them: 1. White Pine concentrates yield extremely high matte grades (65+% Cu) and viscous slags. The viscous slags hinder matte settling causing matte "prill" entrapment in the slag 2. White Pine's total refined copper output is accomplished through fire refining requiring special techniques for impurity removal, especially small amounts of nickel introduced from purchased pyrite and chalcopyrite fluxes. These special techniques result in high-copper slags, refractory to smelting, being reintroduced into the reverberatory furnace. 3. Furnace bottom build-ups resulting in mechanical matte entrapment through the formation of "dams" hindering matte flow. 4. Occasional concentrate fluxing and furnace atmosphere control problems.

Jan 1, 1975

By Paul Hatmaker

Pumice and pumicite are siliceous volcanic substances quite similar in chemical composition , but somewhat different in physical properties , manner of formation , and mode of occurrence . Production in the United States has increased from 23,271 tons valued at $ 94,943 in 1910 , to 56,843 tons valued at $336,099 in 1930. Both pumice and pumicite are included in these figures as it has been impractical to collect statistical data on the separate commodities .

Mar 1, 1932

By Lulie H. Crump

Salient historical data on consumption of fuels and energy have been summarized by State and census district for the years 1960 through 1972. This Information Circular covers States east of the Mississippi, and Information Circular 8705 covers States west of the Mississippi. These data replace previously published compilations of energy consumption statistics by States and districts. Future annual studies are planned using the same Btu conversion factors applied in these two. Information Circulars.

Jan 1, 1976

By B. W. Gandrud, G. T. Bator

The recent introduction of small coal jigs in Alabama to meet the needs of truck - mine operators for cheap and economical cleaning equipment marks another step in Alabama's pioneering record in the mechanical cleaning and preparation of coal . During the past 4 or 5 years a number of these small jigs , with capacity of 5 to 10 tons per hour , have been installed at Alabama truck mines and at a few truck mines in Illinois , Tennessee , and Pennsylvania . Most of the installations have been at mines that specialize in the production of domestic , stoker coal . This report describes three models of small jigs and includes performance data obtained recently on one of the models by the Bureau of Mines, United States Department of the Interior , in cooperation with the University of Alabama, Tuscaloosa , Ala . , for the purpose of comparing it with fullsize jigs on a performance basis . With literally hundreds of truck mines now in operation throughout the country , it has been assumed in preparing this report that there is widespread interest in the availability of small - scale inexpensive preparation equipment for use at such mines in the production of steam and domestic coal and in some instances coal for manufacture of coke . Practically none of the coal from Alabama truck mines is scld to coke - oven plants ; but in some sections of the country truck mines supply a considerable amount of coking coal, and the use of small, inexpensive washers at some of them might be very advantageous during the present war emergency from the standpoint of increasing pig - iron production through improvements in coke quality .

Aug 1, 1943

By Greg Sanders, Michael Gilbert, James G. Shaughnessy

"A new raw water intake from the South Holston River to the Kingsport water treatment plant is under construction. The exploration for the 335 meter long horseshoe shaped tunnel design took advantage of the site topography along the alignment to better define the complex geology consisting of Knox Limestone and Sevier Shale formations separated by a fault zone. To assess the geological conditions and to determine the extent of the fault zone, a 183 meter long horizontal boring and geophysical investigation was performed along a portion of the tunnel’s horizontal alignment. Explorations defined the fault zone width at approximately 5 meters and packer testing along the alignment provided a means of estimating groundwater inflows. As the tunnel excavation advances, comparisons of exploratory data versus encountered conditions will be made. This paper provides details on the geotechnical investigation, lessons learned, and the influence of the geology on the tunnel design. PROJECT OVERVIEW The Kingsport WTP is supplied with raw water via the South Holston River. The City of Kingsport (City) owns and operates the Kingsport Water Treatment Plant (WTP). The existing raw water intake system, consisting of pumps, power supply, raw water piping and appurtenant facilities has been determined to be vulnerable to failure. The original Raw Water Pump Station (RWPS) was constructed in 1928 as part of the original Kingsport WTP project. The 1928 RWPS operated until 1970 when it was replaced by the existing RWPS. This existing system still utilizes the 1928 piping and piping tunnel. Improvements to the RWPS hydraulics and capacity are required to meet the City’s future water treatment needs. The system extracts water from the South Fork of the Holsten River and coveys it via three pressure pipelines to the WTP. The conveyance piping exits the RWPS, ascends approximately 23 m up a near vertical rock outcropping then enters a 120 m long tunnel. Upon exiting the tunnel the piping continues underground to the WTP. The drill and blast tunnel is horseshoe shaped and nominally 3.3 m high by 3.3 m wide. The easternmost 62.3 m of the tunnel is without any type of support. The remainder is lined with concrete. According to the City of Kingsport, the concrete lining was installed in the 1970’s as part of upgrades to the facility. An evaluation of the current facilities concluded that the conveyance piping was in poor condition and required replacement."

Jan 1, 2016

By Andrew Chegwidden, Tara Wilk

Shaft 18B-1 is the second shaft to be constructed as a part of contract C547A along the New York City water supply system Tunnel No. 3. More complex than Shaft 17B-1, this site has an additional 30 m (100 ft) of overburden for a total excavation depth of approximately 78 m (256 ft) through water-bearing overburden soil and 145 m (475 feet) of gneiss bedrock to connect to the underlying Water Tunnel No. 3. round freeing was specied as the method to provide temporary earth support and ground water control for the overburden material. An extensive supplemental geotechnical investigation (SGI) and frozen soil testing program was performed to develop the design of a temporary ground freezing system, consisting of over 7,315 m (24,000 ft or 4.5 miles) of drilling for the installation of 95 freeze pipes. At the start of shaft excavation, the upper sandy silts strata was found to have an unprecedented low thermal conductivity, leaving the frozen soil face approximately 0.6 to 1 m (2–3 ft) behind the cutline. The ground freezing earth support needed to be augmented with ring beams and liner plates to support this soil face and allow for the excavation to proceed and be completed safely.

Jun 23, 2024

By M. A. T. Cocquerel, J. G. Eacott

"Simulation techniques may be used to optimize existing processes and plant operations, and in plant design at the engineering study stage of a project . This paper describes the latter application, using a computer, to optimize the concentrate stockpile requirements of a modern copper smelter.A large open-pit mining operation is envisaged and it is assumed that copper concentrate is smelted in two flash furnaces. The proposed mining plan gives rise to metaffurgical considerations in smelting which dictate that concentrate blending is carried out in the early years of operation in order to eliminate wide variations in the grade of concentrate charged to the furnaces . Stockpiling facilities are therefore necessary for blending purposes and also to provide a strategic reserve of concentrate to ensure continuity of concentrator and smelting operations.The objective of the study is to determine the optimum size of concentrate stockpile required to take account of both metaffurgical and strategic considerations. Two separate simulation models are developed to achieve this objective. The first model is used to determine the minimum size of stockpile necessary for blending purposes to smooth out variations in concentrate grade between 15 - 60% Cu, with associated 34 6% Fe, respectively, and ensure that the concentrate fed to the furnaces does not faff below 12% Fe, which is considered a minimum for good smeltability.The second simulation model covers a projected three-year operating period and indicates the maximum size of stockpile which is likely to develop during scheduled and unscheduled shutdown periods in the concentrator and smelter.Covered storage volume and conveying facilities for the optimum size of concentrate stockpile can be designed based on the results generated by the simulation models."

Jan 1, 1980

By Thomas C. Ruhe

The Bureau of Mines conducted research to determine the safe operating conditions for using recycled (used) lubricating oil from mining equipment as a partial replacement for diesel fuel to make ANFO-type blasting agents. The use of recycled oil (RO) saves energy, reduces oil imports, and reduces mining costs. Low ambient temperatures may cause these recycled oils to become too viscous for proper absorption by ammonium nitrate (AN) prills and result in poor blast performance, safety hazards, and environmental problems. To help quantify and resolve these issues, viscosity, mixing, and performance tests were conducted at various temperatures. Diesel fuels No. 1 and No. 2 were studied separately and in blends with 25,50, and 75% RO. Good quality ANFO mixes (94-6) were produced with dry absorbent prills and blended fuel (No. 1 diesel plus RO) at temperatures as low as -40° F (-40°C) with 75% No. 1125% RO, and at -20°F (-29°C) with 50/50. Diesel fuel No. 2 also made good mixes as low as -30" F (-34" C) with 75% No. 2/25% RO, and at 0° F(-18° C)with 50/50. Reference detonation velocity tests were conducted in 1.4" (3.6 cm) diameter steel pipe at 70°F (21°C) on No. 1 diesel ANFO (94-6), giving an average value of 9722 ft/s (2964 m/s). Comparison tests showed good ANFO performance at low temperatures. Blended fuel ANFO (75% No. 1/25% RO) mixed, loaded, and tested at -40°F (-40°C), produced an average velocity of 9247 Ws (281 8 m/s). A 50/50 blend gave a velocity of 8083 Ws (2464 ds) at -20°F (-29°C). Based on these results, a practical field method has been developed to help evaluate whether a specific oil blend will mix properly with AN at a low ambient temperature. This method will help to promote the safe and reliable use of RO ANFO at low temperatures, with adequate performance.

Jan 1, 2008

By H. Shafick Hanna

The major problems are identified the high phosphorus content and the fine dissemination or encapsulation of mineral impurities, in, ,the iron bearing minerals, A process which combined extreme fine grinding techniques with magnetizing roasting or flotation separation methods, is suggested. By these methods concentrates assaying 60-61 percent Fe exceeding the widely accepted upper limit of 56 percent Fe set for these ores, were produced with 75-90 percent iron recovery. Moreover it was shown that the phosphorus content of these concentrates could be reduced from 0.25 to 0.03 percent phosphorus by acid leaching. A brief discussion on production costs based on current and future developments in iron ore processing is given.

Jan 1, 1980

By J. L. Ellenberger, T. Miller

"A limestone mine in Ohio has had roof instability problems that have led to massive roof falls extending to the surface. This paper describes a collaborative study of these events undertaken by the National Institute for Occupational Safety and Health and the mine owners. The study focuses on the roles that weak, moisture-sensitive floor and weak bands in pillars play in a general instability that led to roof falls at this mine. The NIOSH Stone Mine Pillar Design software (S-Pillar) does not include analysis for weak floor or weak bands and recommends that when such issues arise they should be investigated further using a more advanced analysis. It is important to recognize that without the impact of the floor or weak bands, the calculated inherent stability factor for these pillars is within the recommended design range. Therefore, to further investigate the observed instability occurring on a large scale at the Ohio mine, FLAC3D numerical models were employed to help determine the failure mechanism. Roof-to-floor extensometers were also installed in the areas predicted to have further instability. This case study will provide important information to limestone mine operators regarding the impact of weak floor causing the potential for roof collapse, pillar failure, and subsequent subsidence of the ground surface. This recent case demonstrates that weak floor can be a significant factor in pillar stability and should be assessed during the design stage of the mine.To an area-wide failure (Zipf, 2001). In that case, it appears that the pillars had actually remained intact. However, moisture-related yield of the weak floor caused deformations which passed through pillars and into the roof, triggering roof collapse around the intact pillars (Esterhuizen et al., 2011). This previous case and the case presented in this study, while not identical, both demonstrate that weak floor and/or bands within pillars can be a significant factor leading to instability."

Jan 1, 2015

By Francisco de Assis Altera

Os custos com reparos e substituições de peças, que são submetidas a trabalhos que proporcionam desgastes dos mesmos significam elevadíssimos gastos para as empresas. Os testes de campo geralmente são caros, além de necessitarem de um longo tempo para serem completados. A partir do momento que se notou a necessidade do desenvolvimento de materiais com maiores resistências ao desgaste começou a ser feitas várias pesquisas na área de desgaste abrasivo. De acordo com trabalhos realizados, pode-se concluir que existe uma grande variedade de parâmetros que influenciam os mecanismos de desgaste de maneira geral. Neste trabalho estudou-se o coeficiente de atrito bem como a resistência ao desgaste por abrasão em dois tipos de materiais, sendo uma amostra com revestimento de níquel e uma amostra revestida com liga binária de níquel com 7,3% de cobalto. O enfoque principal foi centrado na taxa de desgaste por abrasão, caracterizado pelo atrito de partículas entre dois corpos em contato. Como material abrasivo foi utilizado uma suspensão de diamante com diferentes granulometrias e foram aplicadas cargas diferentes, totalizando oito ensaios. Nestes, foi possível observar que maiores desgastes estão diretamente relacionados com material de maior dureza, abrasivo de maior granulometria e menor carga aplicada.

Aug 16, 2017

Workers in underground stone mines have a high fatality rate caused by falls of ground from the mine roof or rib. NIOSH recommendations to reduce ground fall injuries and deaths address baskets, mechanical scalers, mechanical bolters, drill steel changing, personal protective equipment, and training. Description of Exposure An informal National Institute for Occupational Safety and Health (NIOSH) review in 1998 identified approximately 17 new underground limestone operations in vari¬ous stages of planning; as many as 35 new underground stone mines are expected by 2005. Many of these new underground stone mines will employ new or inexperienced workers with minimal knowledge of the hazardous conditions that exist underground. Workers in underground stone mines have a fatality rate nearly 20 times that of workers in the manufacturing sector. Three quarters of the fatalities in underground stone mines are caused by falls of ground from the mine roof or rib (Figure 1) [Statistical Abstract of the United States 1985-1999; MSHA 1983-1999]. During 1983-1999, nonfatal ground falls resulted in 140 injuries, or 15% of all underground, lost time stone mine injuries. These nonfatal ground fall injuries resulted in more than 13,800 lost workdays (one third of all lost workdays). Ground falls generate more disabling injuries and time away from work than any other type of incident. [ ]

Jan 11, 2003

By J. D. Forrester

Many have been prone to credit the decline of professional interest in some branches of mineral industry education to the industrialists and other agencies who use our graduates. We hear the cry that industrial salaries are too low, opportunities for advancement do not exist, and the mineral industry specifically and generally is not interested in the engineer's efforts. Perhaps the time now has come when we should "dress-ranks," examine our practices, and publicize and encourage advanced technical training instead of laying all our troubles elsewhere. There can be no doubt but that industry is interested and stands ready and willing to co-operate. This is demonstrated by the numerous grants-in-aid and co-operative industrial projects which have been made available to those relatively few schools which have been encouraging graduate study and research. There is no dearth of research problems in any of the mineral industry fields and the sooner we realize the great opportunities for constructive, technical research in all areas of our profession the sooner we will reap the benefits of our engineering enterprises by closer liaison and broader understanding with industry. An analysis is offered here of the status of graduate work and research in various phases of mineral industry education in the United States. It is

Jan 1, 1949

By D. Q. Cang, G. Duan, H. X. Li, H. Bai

"Life cycle assessment (LCA) is a valid environmental evaluation method and enterprise environmental management tool used in industrial ecology areas. In this paper LCA was newly used to evaluate the environmental impact of manufacturing of alumina by Bayer process in china from two aspects of logistics and energy flow, GaBi software acted as analysis tools with evaluation model established, and several environmental impact assessment criteria were selected based on the actually typical date of Bayer alumina producing process. Evaluation results show that alumina manufacturing by the Bayer process has a great impact on the global warming and human health of respiration, even roasting process gives rise to the greatest impact of winter fog index. Scenario analysis proposed ways of reducing environmental load caused by Bayer process including: (1) the economic and efficient use of mineral processing technology; (2) optimization of energy use, saving power consumption or the use of new more economical source of energy; (3) actively promote the use of innovated technology and equipment in alumina manufacturing and waste such as red mud utilization process.1 IntroductionSince 2002, China is already the world's biggest producer of aluminium, in 2007, China aluminum production has accounted for above 1/3 all over the world, 2009 for 13 million tons and to the end of 2010, China aluminum production is expected increased to be over 15 million ton [1,2,3]. While as the raw material for producing aluminum the alumina production in china has up to 19.46 million tons of the world's total quarter in 2007, by the end of 2009 China alumina production has achieve to 23.78 million tons [4,5]. China has rich bauxite resources with proven reserves about 23 million tons, but the great majority of china bauxite is hard monohydrate diaspore type with low ratio of aluminium silicon, high impurity content and poor aluminum dissolution performance, that cause high energy consumption, long and complex process, high production costs and heavy environment load[6,7]. Before most used alumina production was sintering process rather than Bayer method in china, over the past decade Bayer method has been widely applied instead of sintering process or combination both forming joint process, premise is improving bauxite quality by mineral processing or adding imported rich bauxite mineral[6,8]. In general each ton production of alumina needs bauxite 1.6~2.20t, limestone 0.7~1.7t, soda 0.250kg, fresh water 12.30 cubic meters, in addition to consume large amounts of energy, and emission waste water over 8.0 cubic meters, dust 2.3~5.7 kg, red mud 0.8-1.5 tons. In china Red mud yield nearly 30.0 million tons every year, accumulated stock is approximately 0.2 billion tons, by 2015 accumulative total red mud is expected to reach 0.35 billion tons [9-13].We know aluminium industry and alumina production have produced large waste, make large energy consumption and its environmental impact could not be ignored. Expecting to optimize production processes and achieve resource recycling for this industrial process the proper environmental assessment is very necessary. Currently Life Cycle Assessment (LCA) is generally recognized as the approved tool to achieve the purpose. The essence of LCA tool is to examine, identify and evaluate a kind of materials, product, process, or a system of environmental impact in their whole life cycle. The life cycle of materials or products includes whole process from raw materials obtained to the final disposal, or more ideal with original or other forms of the whole process of recycling [14-17]."

Jan 1, 2011

By O. M. Bishop

The Douglas fluorite property is in the Empire district of eastern Pope County, Ill., which lies near the west boundary of the productive Southern Illinois fluorspar field in Hardin and Pope Countios. Production from mines on the Douglas property accounts for about one-half of the 72,000 tons of fluorspar with which the Empire district is credited. This output was from the Sycamore, Pierce, Slapout, and Empire veins, which are normal fissure veins of little displacement along which there has been local wall-rock replacement by fluorite.

Jan 1, 1949

By Dennis A. Hansen

As part of a U.S. Bureau of Mines program to develop a more continuous titanium metal extraction process that uses domestic resources, a study was made to determine the extraction of titanium (Ti) and iron (Fe) from New York rock ilmenite using fluosilicic acid (H2SiF6). The effects of leach temperature, acid concentration, and particle size were investigated for the rate at which Ti and Fe are extracted from the ilmenite. Within the leach time studied, the extraction data fit a shrinking-core model; the rate-controlling step was diffusion of H2SiF6 through an ash layer resulting from a heterogeneous leaching reaction. The rate is linearly dependent on the H2SiF6 concentration and is inversely proportional to the square of the particle diameter. Using 2.6M H2SiF6 at 85°C, 49% of the Ti and 53% of the Fe in 44-to 74-µm New York rock ilmenite were extracted in 3 h.

Jan 1, 2010

By Christopher R. Winter

Mining companies have sharpened their refocus on their tailings management strategies in recent years. Mining companies with tailings storage facilities that use the upstream construction method have been challenged to track the evolution of industry standards, assess risks, revise design, and communicate design revisions with regulators. While many aspects of best practices and industry standards have evolved in recent years as an attribute of continual improvement, the controlling standard in the design of many upstream dams is understanding the foundational strengths of hydraulically deposited tailings. Following best practices and industry standards, Hibbing Taconite Company managed by Cleveland-Cliffs, began the re-evaluation of foundation strengths underlying a system of upstream dams at the company’s iron ore mine tailings storage facility in northern Minnesota. Initial steps in the re-evaluation require reanalysis of design parameters and recommendations by the Engineer of Record to the Owner, which was followed by a series of meetings with the Technical Review Board to determine an initial path forward. Once a path forward and preliminary design parameters were determined, the Owner engaged with the State Dam Safety Engineer to discuss and seek approval of the plan. With continuous regulatory engagement throughout the process, further refinement of the design parameters for the hydraulically-placed tailings foundations underlying upstream dams began with field and lab geotechnical investigations. Following a review of risk assessments and trigger actions response plans, Hibbing Taconite revised its tailings storage facility operating plans and budget for the coming years. Based on the findings of the re-evaluation, reanalysis, and refinement of parameters, a paradigm shift was realized with the hydraulically placed tailings foundation strengths underlying the upstream system of dams. This paper explores the path that the Hibbing Taconite Company followed to understand the paradigm shift and construct downstream improvements. The plan involved tailings re-characterization, dam design revisions, operating plan reconciliation, budget revisions, wetland permitting, dam safety permit amendments, storm water prevention plans, borrow materials studies, new concrete decant structures and the pursuit to recognize and be consistent with industry standards.

Feb 1, 2024

By Sidney Katell

Continuing the series of cost bibliographies which was initiated with the publication of Information Circular 7516 in October 1949, the present report covers the period from January 1959 through December 1959. The abstracted articles, concerned with all facets of cost engineering in the field of petroleum and chemical plants and related facilities, were obtained from the following sources: 1. Bureau of Mines Information Circulars. 2. Bureau of Mines Report of Investigations. 3. Chemical Engineering. 4. Chemical Engineering Progress. 5. Chemical Week. 6. Coal Age. 7. Coal Utilization. 8. Cost Engineering. 9. Industrial and Engineering Chemistry. 10. Nucleonics. 11. Oil and Gas Journal. 12. Petroleum Engineering. 13. Petroleum Refiner. 14. World Oil. On Oct. 16, 1959 a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers became effective. This agreement provides for the publication of the annual bibliography under the sponsorship of both groups with the work load involved in the preparation divided equally between the two. As a result, the present report partially reflects the efforts of the members of the Association.

Jan 1, 1960

By R. C. Temps, G. E. Aiken

Compania de Acero del Pacifico, S.A., the sole Chilean steel producer, is adding to the expanding Chilean economy with development of the El Algarrobo mine. Expected to go on stream early in 1962, Algarrobo is a conventional open pit mine that will include facilities for ore extraction, crushing and screening, rail transport to the harbor at Huasco, modern ship-loading equipment and maintenance shops. CAP anticipates producing 1.38 mil- lion tons annually of high-grade ore for national and world market consumption. Chilean and North American management and engineering teams combined more than a decade ago in the financing and building of CAP'S Huachipato integrated steel plant. A similar performance is being achieved in northern Chile near the town of Vallenar with the opening of a 50-year supply of iron ore from the Algarrobo deposit. This successful intra-American undertaking deserves special mention in these times when some U.S. foreign assistance programs must be defended, particularly with respect to Latin America. North American financial participation in Algarrobo, through the Export-Import Bank of Washington, represents the greatest portion of the $24 million being invested.

Jan 3, 1962