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By James Gibbs

In order to provide an initial approach to the deposits of oil shale, nahcolite, and dawsonite in the central area of the Piceance Creek Basin in northwestern Colorado, the U.S.B.M. and associated contractor personnel drilled and cased a 96-inch ID shaft to a depth of 2,371 feet. The shaft was constructed using "big hole" drilling techniques and succeeded in giving access to previously inaccessible deposits of the above minerals. This report documents the construction from its beginning in January 1977 to its completion in January 1978. Procedures used and problems encountered are discussed in derail.

Jan 1, 1978

By B. K. Shibler, A. O. Ipsen, W. W. Agey

"INTRODUCTION As a part of the program of investigation of domestic sources of manganese ore, mining engineers of the Bureau of Mines obtained and examined samples of ore from six properties in the vicinity of Pioche, Lincoln County, Nev., and from one property near Caliente, Lincoln County, Nev. As the ores were too low-grade to be acceptable for the direct production of ferromanganese, their amenability to concentration by ore-dressing methods was investigated.In general, the Pioche ores had a low manganese content and, owing to extremely intimate association of manganese minerals with iron oxide and nonmetallic gangue, were refractory to concentration by ore-dressing methods. Only two samples (Zero Gap and Wheeler ores) were amenable to the production of concentrates that would sinter to a marketable plus 35-percent manganese grade. The Prince Consolidated and Ely Valley No. 1.ores were roasted and sintered to produce lead-silver-zinc fumes. The residues were of possible value as manganiferous iron ore. No marketable manganese products were made from Calton semi-oxidized ore, but over 80 percent recoveries of lead, silver, and zinc were made by bulk sulfide flotation followed by Diming of the sulfide concentrate. No satisfactory results were obtained by treatment of Golden Eagle and Ely Valley No. 2 ores.The Cudverwell ore was amenable to the production of high-grade manganese concentrates by ore-drssing methods. However, fine grinding was required to effect mineral liberation, and loss of manganese as slime limited the mangenese recoveries obtainable.In the coarse of the investigations, many data were obtained and compiled, but for the sake of brevity, several data, of secondary importance have been omitted or condensed, and only the tests giving the more promising results are discussed in detail. For convenience, the report has been divided into two parts, one opertaining to the Pioche ores and the other summarzing results obtained by testing Culverwell ore."

Aug 1, 1947

By D. Argyriades, G. Derge, G. M. Pound

The electrical conductance of molten FeS was studied as a function of temperature and composition. It was found that stoi-chiometric FeS (36.5 pct S) shows a minimum specific conductance of 400 ohm-1 cm-1. For the Fe-rich melts the conductivity increases with increasing amount of iron to about 4850 ohm-1' cm-I at 26 pct sulfur. For the sulfur-rich melts the conductivity increases with increasing amount of sulfur until it reaches a maximum of 1300 ohm1 cm-1 for 37.4 pct S and decreases to 800 ohm-1 cm-1 for 38.3 pct sulfur. It is concluded that molten stoichiometric FeS is an intrinsic semiconductor in which the forbidden gap in the electron energy level diagram is quite narrow. Excess sulfur acts as an acceptor impurity in providing a component of positive hole conduction, while excess iron acts as a donor impurity to increase the n-type conduction. K. Bornemann and G. von Ftauschenplatl used a four-terminal, direct-current cell to study the electrical conductance of molten copper sulfide. Their measurements showed a high conductivity, of the order of 100 ohm-1 cm-" and a positive temperature coefficient. From electrolysis studies, Savelsberg2 concluded that molten Cu2S and molten FeS are electronic conductors. Further. he found that molten FeS has a high specific conductance, of the order of 1500 ohm-' cm-', and a small negative temperature coefficient. Pound, Derge, and Osuch,3 using an ac Kelvin circuit and a four-terminal cell, measured the specific conductance of molten Cu,S, molten FeS, and various mixtures. They found that the specific conductance of the solutions followed a roughly additive rule of mixtures. Yang, Pound, and Derge4 showed from electrolysis measurements that the mechanism of electrical conduction in molten Cu2S, FeS, and mattes is primarily electronic. Further, they observed that small additions of CuCl suppress the electronic conduction whereupon the system behaves ionically.

Jan 1, 1960

By Anderson Lúcio de Souza

Foram realizados testes completos de pelotamento para avaliar os efeitos da adição de uma solução de cal hidratada ao pellet feed na etapa de pelotamento. Foram preparadas soluções com diferentes concentrações de cal hidratada e após a mistura das mesmas no pellet feed foram realizados testes de pelotamento onde os principais parâmetros de qualidade das pelotas cruas geradas foram avaliados. O diâmetro médio final das pelotas foi o principal parâmetro influenciado pela adição de cal hidratada. A presença dos íons Ca2+ e CaOH+, em função da dosagem de cal, altera o estado de dispersão do minério de ferro, afetando assim o processo de formação das pelotas. Ainda, os cátions Ca2+ presentes no pellet feed interagem com o aglomerante orgânico e com a bentonita, reduzindo a capacidade desses agentes em controlar o crescimento das pelotas.

Aug 1, 2018

By G. Duncan, K. Winther, R. Ericsson

Distinct trends in grinding mill technology have emerged in recent years. In an effort to optimize overall mill performance for the needs of the End User, broad measures of logistical speed, process flexibility, operational risk, and overall costs now exert greater influence on the specification of grinding equipment. As a result, innovative alternatives to conventional grinding mill structures, supports, drives, feed, and discharge configurations are now being offered and selected with greater frequency. This paper investigates these trends in grinding mill technology, utilizing optimization and decision-theory techniques. In particular, the paper considers how specific advances in process design, product engineering, manufacturing techniques, and mining operations continue to relax technological constraints, enabling further mill innovation. In this context, a methodology is presented, illustrating how proper selection and specification of grinding mill components and configuration can target an optimization of the four End-User performance measures listed above.

Jan 1, 1999

By B L. Coulter, E Wightman, A S. Burrows

With their commitment to sustainable development in an increasingly carbon-constrained world, many resources companies are focused on reducing the energy required to create their final products. In particular, the comminution and smelting of metal-bearing ores are both highly energy-intensive processes. If resource companies can optimise the energy efficiency across these two processing stages, they can directly reduce their overall energy consumption per unit mass of metal produced and thus reduce their greenhouse gas footprint. Traditional grinding and flotation models seek to improve the efficiency of mineral processing, but they do not consider the energy used by downstream metal production, eg smelting and refining. Concentrators and smelters individually may be running efficiently, but are they optimising energy consumption of the overall system? A key step towards answering this question is to understand whether it takes less energy to remove an impurity in the concentrator or the smelter. Analysis of the complete concentrator û smelter process chain may show that there are times when the concentrator should use more energy to reduce the overall energy requirements across the mill and smelter. The new methodology discussed here will integrate downstream processing energy with mineral processing energy, to find the overall most energy efficient circuit design and operating strategy. The proposed methodology includes: determining what grade and recovery positions can be achieved in the concentrator by using different combinations and amounts of grinding and regrinding, thermodynamic calculations of the energy used to process the different concentrate grades to metal, and integrating the concentrating and smelting models to find the lowest total energy for the system. A case study which investigates the effect of increasing regrinding energy on the overall mineral processing û smelting energy consumption is presented. For the copper-nickel sulfide ore investigated the addition of regrinding results in 11 per cent less energy being used in the overall concentrator û smelter process chain per tonne of metal produced. Although regrinding is often seen as an energy-intensive process, in this case study the use of 1 kWh of energy for regrinding reduces the overall energy consumption by 12 kWh. The new mill to melt methodology will allow companies to model energy consumption from mill to smelter with a view to reducing the energy-intensity and greenhouse gas footprint of their processing and smelting operations.

Jan 1, 2009

By E. O. Afreh, R. J. Bowell, E. Hanssen, D. Pohl, S. Abe, R. K. Yao, N. d'A. Laffoley

In the largely preserved laterite profiles at Syama mine, in the savanna region of southern Mali, element geochemistry in the mottled-clay horizon and below can be related directly back to the protolith, but above this, in the ferricrete and cuirasse horizons, the hypogene signature is much modified by pedogenic processes. In tropical rainforest terrains extensive remobilisation can result in wide but weak geochemical targets for gold and pathfinder elements. At the Hire concession in central Ivory Coast, intense recent alteration of the largely intact laterite sequences has modified soil-geochemical dispersion patterns extensively, producing Fe-rich nodular stone lines and obliterating previous patterns and features. Where the upper horizons of the laterite profile have been removed or reworked, as at the Senoufo concession in northern Ivory Coast (savanna) or the Kubi prospect in Ghana (rainforest), all soil horizons can be related directly to hypogene geochemistry. In these truncated profiles, gold and base metal anomalies are essentially those of the lower weathering profile and form narrow but strong dispersion haloes. A good understanding of the geochemical processes active in deeply weathered profiles is required if targets are to be recognised effectively

Apr 1, 1996

By H. P. Rue

The Bureau of Mines has recently collected two samples of crude oil from wells in the Greasewood Flat area of northeastern Colorado. Sample 31310 was taken from the Continental Oil Co.'s well Briggs No. 1 which care in or September 27, 1931, with a maximum production of 940 barrels per day. Sample 31311 was taken from tie Reiter-Foster Oil Co. Is well Ida Johnson No. 1 which came in on August 24, 1931 with a maximum production of approximately 1000 barrels per day.

Jan 1, 1932

By K. Moxham, R. G. B. Pickering

Over the last few years Lonmin Platinum and Sandvik have embarked on a unique partnership of collaboration through a systematic approach to developing equipment to mechanize and automate narrow reef platinum mining. After the initial design and manufacture of the equipment the key aspect is the integrating equipment, people and method into a mining system. Another key a spec of mechanization is the optimization of equipment utilization and this philosophy has ensured continual evolvement of mining methods. This paper describes the trials and development that have resulted in the mining method described as Lonmin mechanized breast.

Jan 1, 2006

By G. W. Jones

One of the major activities of the Bureau of Mines is the promotion of safety in mining and other industries, In this connection, the Bureau determines the explosion hazards' of combustible gases, vapors, and solids and investigates means of controlling and preventing explosions. Many dangers are likely to confront men who must enter a building immediately after it has been damaged. Rescue workers must watch constantly for common gases and vapors that may be present in dangerous concentrations in and about demolished, buildings. Fuel gas is the most common source of danger, although refrigerants, gases from furnaces, flues, fires, sewers, and industrial processes, and gas from bomb, explosions in confined places also constitute definite hazards. To rescuers and trapped casualties, these gases offer the hazards of (1) explosion, (2) toxic effects, including asphyxiation and death, and (3) displacement of air so that the oxygen content of the atmosphere is reduced to or below the danger level.

Jan 1, 1944

In July 1982 the Committee on Underground Coal Mine Safety completed its study of safety in U.S. underground coal mines; the results of the study were published in the National Research Council report entitled Toward Safer Underground Coal Mines. One of the findings of this study was: THERE IS A STRONG CORRELATION BETWEEN MINE SIZE AND FATAL INJURIES. THE FATALITY RATE IN MINES WITH 50 OR FEWER EMPLOYEES IS NEARLY THREE TIMES THAT OF LARGE MINES (WITH OVER 250 EMPLOYEES), AND ABOUT TWICE THAT OF INTERMEDIATE-SIZED MINES (WITH 51-250 EMPLOYEES). Although the Committee explored possible reasons for the higher fatality rate in the smaller mines, it was not able to explain this phenomenon fully. Therefore the Bureau of mines requested that the Committee undertake a supplementary study of fatalities in small underground coal mines. The Committee met in the fall of 1982, discussed the problem, developed an approach to it, approved a program of statistical analyses, and authorized a panel of four committee members to explore the problem in greater depth. The panel, in turn, reviewed the results of the statistical analyses and met with the president of the National Independent Coal Operators Association and with several owners of small underground coal mines for a detailed discussion of the unique problems of small mines. Panel members examined 66 individual fatality reports prepared by Mine Safety and Health Administration (MSHA) inspectors who investigated fatal accidents that occurred in small underground coal mines in 1979 and 1980. This report is the result of those studies, analyses, and deliberations. The first draft was prepared by the panel, but the report has been reviewed and approved by the entire Committee.

Jan 1, 2011

By M. J. Latva-Kokko, CA Snyders, J. R. Peltola, M. K. Kostiainen

It is well known that carbon management is essential for minimising soluble gold losses in carbonin- leach (CIL) and carbon-in-pulp (CIP) circuits. Even so, carbon measurements remain predominantly a manual operation with a low amount of control and automation around CIL and CIP reactors. Carbon inventory, i.e. knowing the carbon concentration in each reactor, is crucial for good carbon management. CarbonSense, a novel in-situ measurement system, was therefore developed for continuous monitoring of the carbon concentration in each reactor and paves the way for more advanced control in gold operations. The carbon management and optimisation system is based on Outotec® HSC Sim dynamic process simulations where each process component is modelled in detail. Generated models are validated with real data from a particular operation. The simulator will allow for the carbon control sequence to be realistically tested and the efficiency optimised by controlling the feed and discharge pumps in a hazard- and risk-free process environment. Furthermore, by combining CarbonSense and Outotec® gold courier (online soluble gold measurements) continuous feed-forward and feedback information can be obtained. The optimiser will then define the best running parameters based on the cost function of gold production versus intrinsic factors such as utility costs and adsorption time. Eventually, the application can be installed parallel with a real process island and it can be continuously calibrated with real-time process data. The dynamic model will then create future predictions for the entire process island. The example case presents a CIL circuit, which is simulated using Outotec® HSC Chemistry Sim and operated through Outotec® ACT (Advanced Control Tool) application. Keywords: Carbon-in-leach, CIL, CarbonSense, carbon management, automated control, simulation

Jan 1, 2020

By R. Stefanko

This Final Report covers the work performed for Contract No. H0377043, "Cables for Face Equipment" from August 1, 1977 to April 1, 1981. It reports the findings in three areas of research: cable protection, circuit-breakers, and high-voltage cable couplers. Laboratory and analytical studies have been conducted in the three areas to determine proper circuit-breaker settings, cable sizes, and coupler performance. Also, an extensive field-monitoring program was established to relate in-mine epxerience to laboratory findings. Further, various pieces of equipment was designed for laboratory testing, particularly in the area of cable reeling and unreeling.

Jan 1, 1981

By Frank R. Corwin, Selden S. Rodgers

PAGE I. Introduction,........... 383 11. Brief History of Present MacDoUgall Plant,.... 384 III. First Experimental Work on Increasing Capacity of Furnaces, 385 IV. Effect On MacDouRall Plant of IncreaBed Draft from New Smelter Stack,,.......... V. Increasing the Capacity of the MacDouGall FurnaceS,.. 391 (A). Test of Arthur Crowfoot on Increasing Capacity,.... (a). Description of Test,........ (6). Discussion of Results Obtained from Test,... 393 (B). Investigation Carried Out by John A. Church, Jr.,... 395 (a). Advantages of High Speed,......398 (C). Effect on Regular Operation of Department by Applying Results Obtained from Experimental Work ..... 399 (D). Fundamental Principles Involved in Increasing the Tonnage, . 400 VI. Treatment of an INcreased Amount of Ore Screenings,.. 401 VII. Maximum Percentage oF Ore Screenings in a MacDoUGall Feed, 403 VIII. Tests to Further Increase Capacity of Furnaces,... 406 IX. Tests to Decrease PercentaGe of Flue Dust made by MacDouGall Furnaces,............. (A). Repath-Marcy Furnace......... 408 (B). Modified Hepath-Marcy Furnace,....... (C). Crouse Furnace Designed for Dust Prevention,.... 413 (a). Tests on Crouse Furnace,....... X. Concrete Hearths,.......... 419 XI. Conclusion,............ I. Introduction. Since the first installation of MacDougall roasters at the Great Falls smelter of the Anaconda Copper Mining Co., the capacity of the furnaces.has been more than doubled. During the first nine or ten years of the operation of the MacDougall department the tonnage treated by the furnaces remained practically unchanged. Experimental work carried out in 1906, however, showed that increasing the draft of the furnaces would bring about an increase in capacity. In 1909 the MacDougall department was connected to the new smelter stack and

Jan 1, 1914

This study was conducted to determine the feasibility of using large tractor dozers in land reclamation of strip-mined areas. The procedures used are patterned after engineering models developed for evaluation of military ground vehicles in cross-country operations. Tractor dozer manufacturers furnished information on capabilities of existing equipment and ideas on the practicability of using dozers larger than those currently available Generally, they believe that current dozers in the 500? to 700-horsepower range are about as large as can be built and remain economically feasible. However, one manufacturer has a wheeled dozer rated at 1200 horsepower, and another is testing a tracked dozer of about the same horse-power.

Jan 1, 1975

By Lawrence Williamson, Randall J. Essex, David P. Field

As part of a $2.2 Billion bridge project that will link Indiana and Kentucky, an interchange project northeast of Louisville will require the mining of a 6-lane tunnel system about 2,000 ft long in order to cross beneath the historic Drumanard Estate. This paper will discuss preliminary engineering that has been undertaken to compare two-bore and three-bore layouts, the planning of an exploratory tunnel facility, and the potential for including a test chamber to investigate the ability of high capacity roadheaders to mine the 22,000 psi limestones.

Jan 1, 2005

By Marc C. Bétournay

A mine production locomotive, the world?s first applied industrial fuelcell vehicle, has been designed and tested in the context of a number of proof-of-concept projects supported by the Fuelcell Propulsion Institute, an international consortium of stakeholders dedicated to facilitate the commercialization of fuelcell vehicles. The locomotive?s simple electric-powered motor and controller system was ideal to study a number of requirements related to fuelcell power application: hydrogen power plant operation, underground hydrogen use, risk and regulatory requirements, production performance versus the conventional battery-powered locomotive version under measured duty cycles and production requirements, power plant design improvements for other fuelcell vehicles, and cost-benefit aspects. This article will focus on the design and testing aspects of this project which has led to successful performance demonstrations of the vehicle under surface and underground conditions at two mines. It will also present information on the creation of a safe, reliable and efficient power plant which fulfilled its design objectives, including longer productivity time for a given vehicle fill-up.

May 1, 2003

By William A. Hustrulid

An overall summary and the individual reports of eight workshops to determine research and development needs in western mining ore presented. Problem areas are identified, and recommendations regarding priorities, funding sources, and prime movers are made. The objective of this contract was to identify research and development needs for advancing mining technology as well as health and safety measures for western U.S. Surface and underground mining. This was accomplished by convening a series of workshops where problems could be thrashed out by producers of trona, uranium, open pit copper, underground salt (from the Midwest and New York), underground metal and nonmetal, etc. In addition to problems, future priorities, funding, and the desicion as to who should be the prime mover on R & D were discussed.

Jan 1, 1976

By Qing Wang, H. Sevim

Belt network simulators are the most widely used models in the design of belt networks. The simulators developed in the past two decades are reviewed and their limitations are discussed. To overcome these limitations and to provide a design model that can be used efficiently in real-life applications, a comprehensive non-simulation model has been developed. The features of this model are briefly discussed. A real example is used to demonstrate the model's superiority over belt simulators

Sep 1, 1991

By K-H. Frohne

This report presents a study of the Cooper sand of the Fork Run pool of Warren and McKean Counties, Pa., and a prediction of the secondary oil recovery by gasflooding the reservoir. A computer program employing a modification of the Craig, Geffen, and Morse secondary recovery calculation was used to make the gas flood performance forecast and is presented in the appendix. The Cooper sand reservoir in the Fork Run pool lies at a depth of about 1,900 feet and covers an area 1/2 mile wide by 2-1/4 miles long. Original oil in place is estimated to have been 8,266,000 STB. The primary recovery mechanism is solution gas drive, and ultimate primary recovery may reach 20 percent over a well life of 90 years. Two computer predictions were made for gas flooding the Cooper reservoir. The first was for a 25-acre pilot five-spot utilizing existing wells, but project economics were poor since only 25 percent of injection gas is utilized for pilot oil recovery. Recovery was 71,000 STB, or 22 percent of oil in place at flood initiation, but required 25,700 scf gas injected per STB of oil recovered. In the second prediction, pilot area performance was projected for the entire Fork Run pool, and economics became good. Recovery was 1,753,000 STB from 25 five-spots after the injection of only 6,400 scf per STB of oil recovered.

Jan 1, 1969