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By R. Laird Auchmuty

A NUMBER of factors, of varying importance, should be considered in assessing mineral land-here specifically coal land -for tax purposes. (1) Is the coal developed or un- developed'! (2) If undeveloped, is it surrounded by active development in adjoining properties? (3) Accessibility of railroad facilities to the property. Sometimes the railroad itself is of importance. (4) Cost of development of the seam under consideration, whether it can be developed by a drift from the outcrop or whether it will require deep and costly shafts or slopes. (5) Is it definitely known that the coal seam being assessed is of minable thickness and quality on the property? (6) Thickness of recoverable coal from the seam. (7) Quality of the coal. (8) Is the seam being assessed likely to be more costly to mine than other seams in the same district? (9) Is there an active market demand for coal from the seam being assessed? (10) Is the coal held only as protection to surface structures and in such location that it can never be mined? (11) Is the coal in a solid piece or is it in pillars that have been standing for some years as a result of incomplete mining in an old operation? (12) Expected percentage of recovery from the seam being assessed as determined by present mining practice in similar properties. (13) Value of the seam as indicated by sales of similar mineral rights in the immediate district. (14) Current royalty rates of leases for coal in the seam under consideration.

Jan 1, 1939

By J. J. deBarbadillo

This Bureau of Mines report describes a process for recovering chromium and other metals from superalloy scrap. Laboratory-scale experiments were conducted to test a complex flowsheet utilizing a wide range of extractive metallurgical operations. The novel basis for the process is the fonnation of a sulfide matte in which chromium is concentrated in a discrete chromium sulfide phase. Mineral processing and hydrometallurgical procedures are used to separate chromium sulfide from the other matte constituents. The products of the process are a chromium-nickel alloy suitable for reuse in the superalloy industry, electrolytic nickel, electrolytic cobalt, and iron-molybdenum residue. Recovery of the principal elements contained in the scrap is chromium--93 percent, nickel--99 percent, cobalt--96 percent, and molybdenum--92 percent.

Jan 1, 1981

By George Filz, Morales, Carlos, Bertero, Filippo Maria, Alessandro, Leoni

"The Deep Mixing Method (DMM) represents a viable solution to improve adverse geotechnical properties of foundation soils for many practical applications. A pre-construction soil investigation campaign is necessary to assess soil properties and to retrieve samples of different soil layers for a laboratory Bench Scale Testing program (BST). The BST has to be designed using various binder types, binder contents, and water/cement ratios in each of the soil types. Following the laboratory program, a full scale Field Test (FT) is typically necessary to verify the results of the BST. This paper will highlight the differences and the importance of performing both pre-construction laboratory tests and field tests to ascertain the proper mixing parameters in the different soil layers. Comparative analyses and interpretations between the lab and field stages, along with accumulated information about soil properties and quality control (QC) results, allow fine-tuning the production parameters throughout a project. Three Deep Mixing Method projects, where both laboratory and field tests were executed, are illustrated: (1) The LPV 111 Project (New Orleans, LA, USA): DMM was used for ground improvement/foundation strengthening to stabilize and support the burden of a new levee raise; (2) The Rio Puerto Nuevo Project (San Juan, PR, USA): DMM was applied to improve the soils adjacent to a 90"" forced sewer main relocation and to improve the soils for the base of a new drainage channel; and (3) State Road 83 (US 331) over Choctawhatchee Bay project (Walton County, FL, USA): DMM was applied to stabilize the causeway sections of the bridge enhancement project. Data recorded during laboratory and field tests for these projects were analyzed and interpreted to select the most appropriate construction parameters to provide a final high-quality product.INTRODUCTIONThe Deep Mixing Method (DMM) represents a viable solution to improve adverse geotechnical properties of foundation soils in many situations. The effectiveness of working parameters depends largely on the physical and mechanical properties of the soil to be treated. Therefore, well designed laboratory and field test programs, aimed to disclose the interaction between the site-specific soils and the mixing parameters, are essential to achieve the desired end product.Generally a pre-construction soil investigation campaign has to be performed to assess soil properties and to retrieve samples of different soil layers for the laboratory Bench Scale Testing programme (BST). The BST has to be designed using various binder types, binder contents (or cement factors - CF), and grout water/cement ratios (W/C) in each of the soil types; the selection of the different combinations and dosages for the BST is based on past extensive experiences on similar materials. Following the laboratory programme results, a full scale Field Test (FT) has to be designed and executed, installing several DMM elements to verify the results of the BST and fine tune the construction parameters, with the appropriate binder type and dosage and the most effective equipment and tool configuration."

Jan 1, 2015

By J. H. East

Potash is one of the essential chemicals used in fertilizing soil deficient in natural minerals . Europe uses a large tonnage of potash in the form of easily soluble salts , and this is particularly true of those countries where the natural minerals in the soil have been exhausted owing to intensive cropping of the land . The application of potash to the soil in these countries is essential if normal crops are to be obtained ; during the war , some European countries were unable to obtain sufficient potash , and productivity of the farming areas declined seriously . • The largest -known deposits of potash in the world ; with the possible. exception of Russia , occur in Germany , and the German output of processed salts constituted about 65 percent of world production prior to the war . The German potash-plant installations are large , modern , brick and steel construction and apparently built for a planned operation of many years . Two districts produced approximately 80 percent of the German potash; the Werra -Fulda district , near Vacha , had the largest production , and the Sudharz district , near Nordhausen and Sonderhausen , was second . (Fig . 1. ) Hannover and Stassfurt were two smaller producers . Potash fertilizers are rated in terms of potassium oxide (K20 ) . The usual basis for calculation of production or application of the salt is to reduce the potash content to 40 percent K₂0 .

May 1, 1947

By M. J. Gavin

Within the past three years numerous inquiries for information on oil shale have been received by the Bureau of Manes. These inquiries have been increasing to such an extent that it has seemed advisable to issue a short paper prior to the publication of a bulletin on the subject, giving a, general discussion of the subject and a comprehensive list of references, so that those interested in the details of obtaining oil from shale can find additional information without much difficulty. Some of those who desire information are interested only in a general discussion of the subject, or are not in a position to refer to books and' articles describing the industry. The material for this paper is largely derived from published information on oil shale. Much of the information is obtained-from the books and articles mentioned in the list of references, and has been compiled with the intent of furnishing information to those not interested in all the details.

Jan 1, 1921

By Dilip Banerjee

"This paper discusses the Advanced Technology Program (ATP)'s support over the last decade to the development and use of process modeling as a tool to address some of the challenges faced by the U.S. metal casting industries. A particular focus will be given to highlight how process modeling can be used to improve the manufacturability of components needed for high performance and critical applications. The challenges associated with the design and production of thin-walled, cast parts with intricate and complex internal geometries will be discussed. Modeling issues associated with the control of the final grain structure in the solidified parts will also be addressed. This paper will describe the advantages of using appropriate mathematical models for designing new alloys for use in various applications.Finally, the role that ATP has played in uplifting the U.S. technological base through partnerships with industry and academia in high-risk research in order to bring to market new and improved products for the broader benefit of the nation will be discussed.ATP's BackgroundIn the 1980s, U.S. industries were losing market share to low-cost, high-quality manufacturers from Asian countries. Corporate leaders and policy makers determined that in order to sustain and grow market share, U.S. industries needed to improve their competitiveness and productivity through product and process innovation. There was evidence that companies were systematically under-investing in leading-edgetechnologies and failing to complete the development of new technologies [l]. There were also arguments in academic circles that pointed to a potential market failure in the area of early-stage technological developments. These concerns provided impetus for creation of the Advanced Technology Program (ATP) within the National Institute of Standards and Technology through the Omnibus Trade and Competitiveness Act of 1988. Through a rigorously competitive, cost-shared partnership with industry, ATP fosters the development and broad dissemination of high-risk technologies that offer the potential for significant broad-based economic benefits to the United States."

Jan 1, 2004

By F. Chachula, A. Molinaro

"Sulphide mineral flotation operations continuously strive for a balance between mineralogy, mineral liberation, circuit conditions and reagent solutions to maximize the production rate and recovery of payable metals. The Taseko Gibraltar copper – molybdenum mill operations underwent an extensive project focusing on the fundamentals to identify the effects of process conditions and mineral liberation to improve the bulk circuit copper – molybdenum recovery efficiencies in the bulk flotation circuits. This discussion will provide process data that demonstrates; 1) fundamental relationship between mineral liberation to recovery and grade, 2) flotation circuit condition testing and optimization, 3) reagent combinations resulting in efficient/economical mineral recovery, and 4) the development of a xanthate free reagent solution. The data presented and discussed will also touch on flotation parameters including pH, retention time, kinetics and the effect on bulk circuit recovery performance.INTRODUCTION Taseko's is the owner (75%) and operator of the Gibraltar copper-molybdenum mine, located in south-central British Columbia, the second largest open pit copper mine in Canada and the largest employer in the Cariboo region. Taseko restarted Gibraltar in 2004. From 2006 until 2012, the company invested ~$700 million to expand and modernize the operation which was originally scheduled for demolition when the company acquired it in 1999. In the spring of 2011, construction commenced for Gibraltar Development Plan 3 (GDP3). GDP3 included the construction of a standalone 30,000 ton per day concentrator, built adjacent to the existing 55,000 ton per day facility. The new design capacity of Gibraltar was designed to be 85,000 tons per day. An integral part of the project was a new molybdenum recovery facility. In addition to the new concentrator, the mining fleet was upgraded with a new mining shovel, production drill and ten haul trucks (Taseko, May 2015). In May of 2015, the Company completed an updated mine plan for Gibraltar featuring a 50% decrease in strip ratio. This new mine plan was a result of a detailed, six-month engineering study and forms the basis of an updated NI 43-101 compliant reserve (Taseko Announces Improved Economics At Its Gibraltar Copper Mine, 2015). The new mine plan took into account lower milling costs as a result of the modernized processing facilities (Taseko, May 2015)."

Jan 1, 2018

By Joseph Cervik, Gerald L. Finfinger

This Bureau of Mines publication reviews underground methane drainage pro- grams being conducted in various coalbeds. Equipment used in drainage programs such as drills, underground pipelines, and methane monitoring systems is described.

Jan 1, 1980

By E. W. Felegy

Since 1920, the Bureau of Mines and, other agencies have conducted numerous investigations of methods of communication for use in mines in times of disaster or emergency. The results of these investigations have been reported in various publications (3, 4; 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16). In November 1944, the Bureau of Mines resumed the study of emergency underground communications. Until March 1946, the program was directed toward reexamining methods of underground communication that indicated possibilities of success. Since April 1946, the principal interest of this investigation has been in methods of application of radio to communication in mines, low-frequency radio seeming to offer the most promise as a successful method of emergency mine communication. Results achieved in reexamining other methods and in the investigation or the application of low-frequency radio between November 1944 and September 1946 were reported previously in a publication entitled "Some Studies on Emergency Mine Communications".

Jan 1, 1948

By D Hillier, A Giblett, K Parker, V Ramsell

Kalgoorlie Consolidation Gold Mines (KCGM) operates the Kalgoorlie Super Pit open cut, Mt Charlotte underground mine, Fimiston process plant and Gidji Roaster facility for joint venture partners Newmont Mining Corporation and Barrick Gold. In 2004, the Fimiston plant was upgraded by the addition of gravity concentration to the Fimiston and Mt Charlotte grinding circuits, including the installation of a central intensive cyanidation reactor to process the gravity concentrates. The gravity project was justified after detailed analysis demonstrating an expected increase in overall gold recovery of approximately one per cent, in addition to reduced elution costs and reduced gold inventory in flotation concentrate stockpiles. The gravity circuits were commissioned in August 2004, and have since consistently recovered 10 to 20 per cent of the gold present in the KCGM ore, delivering a reduction in coarse gold losses equivalent to 0.45 per cent additional metal recovery and contributing to improved metal accountability.CITATION:Giblett, A, Hillier, D, Parker, K and Ramsell, V, 2012. The impact of gravity gold recovery at Kalgoorlie Consolidated Gold Mines, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 199-206 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By Jr. Watts, B. K. Cantrell, D. H. Carlson, K. L. Rubow, S. T. Bagley

"Permissible exposure limits (PELs) have been established for gaseous pollutants, carbon monoxide (CO), carbon dioxide (CO), nitric oxide (NO), nitrogen dioxide (NO2), and some gas-phase hydrocarbons emitted in diesel exhaust. There is, as yet, no PEL recommended for diesel exhaust aerosol (DEA), nor is there a standard method for sampling this aerosol.The University of Minnesota and the U.S. Bureau of Mines have collaborated to develop a personal diesel exhaust aerosol sampler (PDEAS) which utilizes size-selective inertial impaction and gravimetric analysis. During the field tests of this sampler, numerous air quality measurements were made in underground coal mines that use diesel equipment.The mine mean DEA concentrations for the five mines surveyed, determined with the PDEAS in the haulageway, was 0.89 mg/m3, with a standard deviation of 0.44 mg/m3. DEA contributed 52 % of the respirable aerosol at this location.In three of the mines filter samples were collected for DEA-associated polynuclear aromatic hydrocarbons (PAHs) and biological activity determinations. Two of the mines were also monitored for the major gaseous constituents found in diesel exhaust. In general, the PAH and biological activity levels were similar for all three mines, and indicate that up to 25 % of the haulageway concentrations may be contributed by outby diesel vehicles. Measured concentrations of CO, CO2. NO, NO2, and SO2, were well below regulated levels.INTRODUCTIONDiesel exhaust contains pollutant gases, such as carbon monoxide, carbon dioxide, nitric oxide, nitrogen dioxide, and gas-phase hydrocarbons, as well as DEA. Much of the health-related concern focuses on DEA and associated organic compounds (Watts, 1992a). A wide variety of these PAHs have been identified and some are known carcinogens and/or mutagens. The U.S. Mine Safety and Health Administration (MSHA) has proposed new PELs for these and other contaminants (MSHA, 1989). MSHA has also published an advance notice of proposed rulemaking to establish a separate PEL for diesel particulate (MSHA, 1992)."

Nov 1, 1995

By Y Lanwin

The Australian mining industry, a cornerstone of the nation’s economy, is on a journey towards greater equity and inclusion. Th paper introduces a comprehensive exploration of how universal design principles, stemming from architectural roots, have evolved through automation and digital technology into the more encompassing frameworks of inclusive design and equitable design. The paper proposes a practical framework for those involved in work, facilities and equipment design in the mining industry to identify and assess for equity and inclusion. Universal Design emerged in the 1960s with a primary focus on architecture, aiming to create spaces accessible to people of all abilities. Its foundational principles sought to ensure equitable use, flexibility, simplicity, perceptibility, tolerance for error, low physical effort and optimal spatial considerations. Over time, these principles evolved and expanded beyond physical spaces, finding applications in various fields, including technology, education and transportation. In response to advancements in technology and a growing understanding of the multifaceted nature of diversity, Universal Design evolved into Inclusive Design. Inclusive Design goes further than mere accessibility, considering a broader spectrum of users with varying cognitive, sensory, cultural and socio-economic backgrounds. It emphasises user centred design, customisation options, diverse user research and continuous iteration. Equitable Design emerged as a framework that addresses not only the diversity of needs but also systemic disparities. It emphasises fairness, justice and the elimination of structural inequities. Equitable Design encompasses accessibility and affordability, representation and diversity, ethical considerations and community engagement. This paper will explore the applications of these design principles through a series of case studies including village and on-site facilities, remote operations and office based work design and technology design. By applying these frameworks in a mining context, the paper proposes that mining companies and suppliers can improve diversity, equity and inclusion leading to safer, more engaged and productive workplaces.

Apr 16, 2024

By Denis Dwyer

[This paper describing mining, treatment methods, and costs at Plant No. 1 of the Western Indiana, Gravel Co. at Lafayette, Ind., is one of a series on gravel and sand mining being prepared for and published by the U. S. Bureau of Mines. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total costs. It is recognized that publication of total costs might in many instances cause embarrassment to individual producers, as well as to industry as a whole. On the other hand, operating costs are essential to e technical discussion and study of the methods employed, The attention of the reader is specifically called to this differentiation in order that no Misunderstanding of the scope of the cost tabulations shall ensue.]

Jan 1, 1933

By S. Zhao, S. P. He, M. Y. Zhu, Y. Tao

"The effect of two refining slags (A: 1.0–1.8 CaO/Al2O3 ratio, 11–20 wt% SiO2; and B: 1.0–1.2 CaO/SiO2 ratio, 25–35 wt% Al2O3) on the inclusion morphology of a carbon structural steel (Q235B) was studied by controlling the balance between the steel and the refining slag at 1600ºC in a Si–Mo resistance laboratory furnace. The results showed that most of the inclusions in the molten steel balanced with slag A were formed by a lowmelting CaO–MgO–Al2O3–SiO2 system with a total oxygen content (T[O]) being fixed at 6–13 ppm. The inclusions in liquid steel balanced with the slag B were mostly formed by the CaO–MnO–Al2O3–SiO2 system, with T[O] controlled to 19–26 ppm. The overall size of the inclusions under balance conditions was higher in the steel reacted with the slag B than that reacted with slag A, with the latter showing more inclusions smaller than 3 um. In order to generate a large number of spherical CaO–MgO–Al2O3–SiO2 inclusions smaller than 3 ??m while decreasing the T[O] in the resulting steel, the composition of slag A should be used. This composition allowed improving the cleanliness of the slab, and is also advantageous for the castability of the molten steel. IntroductionThe sample used in this study was a typical carbon steel manufactured by CQ Steel. The galvanized, tinned, and plastic composite steel plates made of the original plates are used extensively for decorative panels, general dust pipes, drums, instrument cases, switchboxes, and train cars, among other uses. The target control composition is shown in Table I. The S and P contents are usually fixed during production below 0.020 and 0.025 wt%, respectively, with the aim of reducing longitudinal cracks on the slab surface."

Jan 1, 2017

By W. W. Adams

Coal mining in the United States, had a somewhat higher death rate per million man-hours of exposure among the employees in 1937 than in 1933 to 1936. However, the rate in 1937 was lower and therefore more favorable than that in any year since 1921 but previous to 1933. The nonfatal injury record, which began in 1930, was lower and therefore better in 1937 than in any other year since 1930. Separate figures covering bituminous-coal mines in all States showed a lower fatality rate in 1937 than in any year since 1920 but before 1933, and a lower nonfatal injury rate than that of any year since 1930 except 1933 and 1936. Reports for anthracite mines in Pennsylvania revealed a better safety record for fatal accidents in 1937 than in any year since 1930 except 1933, 1934, and 1936 and a better record for nonfatal injuries than in any year since 1930 except 1933.

Jan 1, 1940

By R. V. Higgins

The results of two separate but related studies are given. In the first study, four equations were tested; the object was to determine which would produce a curve that would best fit data points that represent a trend of declining oil production in 90 California fields. Two conventional equations (the Arps and semilog) and two novel equations (extreme-c and double semilog) were tested. The curves were first fitted to the initial 9 years of the 15-year production data and then extrapolated for 6 years to determine how well the extrapolated curve would fit the data points. The generated curves were also extrapolated beyond the last data point to predict rates of future production. The results of the first study showed that no equation was clearly superior to the others in all respects. The semilog equation resulted in the best fit to production data for the first 9 years, but the Arps and extreme-c equations produced a better fit for the extrapolated data for the period of 9 to 15 years. The Arps and extreme-c also gave more realistic production rates when extended to the point where cumulative production equaled reserves. A second study was made to determine if the least-squares technique applied to the Arps equation would result in more accurate extrapolations. The merits of the logarithmic and the nonlogarithmic forms of the Arps hyperbolic equation were also tested. For the logarithmic expression, it was found that one of the constants of the Arps equation reached a value so small or so large that the equation was not applicable to the data of 40 of the 90 California fields. The nonlogarithmic form of the Arps equation was applicable to neither the same 40 fields nor to a few additional ones. When the data and the Arps equation were compatible, the use of the least-squares technique as compared with other methods improved the extrapolation accuracy somewhat.

Jan 1, 1971

By Nina Bianco, Diana Drinkwater

MetSkill is a professional development program for metallurgical engineers that integrates with normal duties in their first one or two years of service. Graduates work together on a structured technical project, facilitated by specialists and supported by formal learning, and ultimately reported to their technical managers. The program enables graduates to “fill the gaps” in their undergraduate education, which is increasingly pertinent as engineering degrees become more general. Participants report that they enjoy the focus on more challenging (rewarding) aspects of their jobs and feel more confident about problem solving. Sponsor companies add that the relationships developed with external technical specialists enhances opportunities for innovation and development. MetSkill was delivered to two major resource companies in Australia in 2012. This paper provides an outline of the program and the reasons for its success, and demonstrates how the learning model could be applied to groups of graduates in other engineering disciplines.

Jan 1, 2014

By Beatrice Pierre, Juan Carrasco

Altonorte began as a concentrate roasting operation in 1988 under the name of Refimet. In 1993, a copper smelter was built with a design capacity of 203,000 tonnes per annum of concentrate. Since 2001, many technological advances have been made in Altonorte, where the biggest Noranda Reactor in the world is installed being the first Noranda Reactor reaching above one million tonnes of copper concentrates processed per annum. In 2013, Altonorte was acquired by Glencore. Recently due to various new environmental regulations in Chile, Altonorte has evolved to new standards of operation in order to reach the vision of becoming a World Class Smelter. This paper describes the path followed to improve safety, environmental performance, process capacity, reliability, and productivity. The foundation for the growth and success in Altonorte is our People. Employee engagement and branding of our cultural journey is what allows Altonorte to face the future with the certainty of becoming a World Class Smelter. INTRODUCTION Altonorte is located in Antofagasta, the mining capital in the north of Chile and is the last smelter built in Chile practically completed with second hand equipment. The biggest technological change in Altonorte occurred during the phase 3 expansion in 2003, where the old Reverberatory furnace was shut down and replaced by the biggest Noranda Reactor installed in the world. The vessel measures 5.3 m × 26m. ºAdditionally, this project contemplated a new rotary dryer, three (3) new Peirce Smith converters, new anode furnaces and a new Acid plant. The nominal capacity was to treat 816.000 tons of new concentrate per year. In 2008, a new expansion phase was implemented where a new double absorption acid plant replaced the oldest acid plant. Bottlenecks such as blowing capacity and oxygen availability were solved installing a new air blower and a new contract was negotiated with our oxygen supplier to increase oxygen availability up to 683 tpd. This improvement defined the current nominal capacity of 1.100.000 ton of new concentrate per year. Current process description All concentrates are received by trucks directly from domestic mines or from the Antofagasta international port in cases of imported concentrates; the concentrate warehouse has a capacity of 25 kt where the blend is prepared to feed the smelter.

Jan 1, 2019

By T. A. Lloyd

The use of tank cells over the years has provided a means for low cost, space efficient, extra capacity in existing flotation circuits. In some cases, new plants have selected tank cells as the machine of choice. Typical tank cells use high efficiency impellers for mixing, which results in low power draw. Unfortunately, these mixers have poor aerating characteristics that compromise metallurgical performance. This has all changed with Outokumpu's new flotation concepts. Outokumpu has recently developed the HG or High Grade flotation cell that can provide higher recovery with better selectivity while maintaining the simple operation of conventional cells.

Jan 1, 1993

By James R. Boyle

The value of Alabama's nonfuel mineral production in 1987 was $446.6 million, an increase over that of 1986 and the first increase in 3 years. Alabama was second in the Nation in production of bauxite and ferroalloys; third in bentonite, crushed dolomite, crushed marble, and fire clay; and fourth in masonry cement. Trends and Developments.-Employment in the minerals industry remained relatively low for the second year even though the overall unemployment rate dropped to 7.9% by December. Employment in mining and primary metals dropped about 10% and 2%, respectively.

Jan 1, 1989