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By Catherine C. Kilgore

The Bureau of Mines investigated the availability of lead and zinc from 104 domestic mines and deposits. Fourteen primary lead and fifty-three primary zinc operations with in situ demonstrated resources containing 27.3 million metric tons (t) of lead and 53 million t of zinc were subsequently evaluated. Potentially 17.5 million t of lead and 2.4 million t of byproduct zinc could be recovered from 14 primary lead operations. Economic evaluations performed in constant January 1982 dollars determined a long-run total cost per pound of recoverable commodity. Including a 15-pct discounted-cash-flow rate of return (DCFROR), 59 pct of primary lead was potentially available at or below $0.32 per pound of lead. Potentially 40 million t of zinc and 5.6 million t of byproduct lead could be recovered from 53 primary zinc operations. Ninety percent of the recoverable zinc is potentially available from currently nonproducing mines and deposits, and a weighted average of their long-run total costs was determined at $0.98 per pound of zinc. At a breakeven (0-pct) DCFROR, these non producing operations had a weighted average long-run total cost of $0.58 per pound of zinc. Sensitivity analyses illustrated that operations that recover byproducts were most sensitive to fluctuating metal prices, producing operations were more sensitive to increased smelter treatment charges, and nonproducing operations were impacted most by the DCFROR.

Jan 1, 1983

By Gordon T. McKenna

"Syncrude Canada Ltd. is developing new concepts in lease-closure landscape design for its Oil Sands Leases 17 and 22 in northeastern Alberta. Closure planning is becoming an integral part of the planning cycles and of the lease operation. By incorporating closure planning into the day-to-day operation, the company will achieve acceptable lease closure in an economical manner. Ultimately, Syncrude will achieve lower operating costs through innovation in mine planning and a reduction in residual liabilities.New concepts being evaluated for lease-closure landscape design include: designing for closure, use of landforms and natural analogs, self-armouring bouldery ground, robustness in design, landform grading, terrain analysis of reclaimed land, geotechnical hazard assessments, choices in closure design timeframes, passive maintenance, determining post-closure monitoring goals, engineering tailings, engineering other substrates, use of test plots and field demonstrations, geomorphologic monitoring of reclaimed lands, defining closure goals, and visiting other mines. These concepts are being formalized under the new discipline of Landscape Engineering."

Jan 1, 1996

By Brian M. Harney

The technique of remote sensing, used for many years by earth scientists, is being applied to the detection and monitoring of air pollution. Instrumentation being developed is of a very diverse nature and is effective, Fn varying degrees, at ranges from 1,000 meters to the altitude of a space satellite. This paper describes a number of the recent developments in this new field. Instruments based on spectroscopic, laser, and photographic systems are discussed. Sensors are being developed which utilize correlation spectrometry, interferometry, Raman scattering, Mie scattering, laser line absorption, and simple photographic detection.

Jan 1, 1973

By K Vallo, T Haimi, J Pihlasalo, J Hamuyuni, M Lindgren, F Tesfaye

Decarbonisation of the steel industry has recently attracted a lot of research and technological development. Most of the technological developments are centred around the replacement of blast furnace (BF), which has been the main primary smelting furnace in the ironmaking step of steel production. Replacement of the BF is not an easy task because of BF’s many established capabilities over the years, especially its ability to use low-grade iron feed. In this regard, Metso has developed its own technology, Metso’s Outotec direct reduced iron (DRI) smelting furnace, to tackle this problem. The recently developed six-in line electric furnace for DRI smelting can be used for primary smelting of DRI from blast furnace grade iron ore. Unlike the electric arc furnace (EAF), the DRI smelting furnace can handle larger slag volumes that emanate from the high gangue in BF grade DRI. Therefore, fluxing plays an important role in operating the DRI smelting furnace. This paper presents fluxing options and proposes slag quality and operating windows for the DRI smelting furnace. Also, the effect of slag on refractory durability will be discussed.

Jun 19, 2024

By Lloyd R. Nelson

Selective carbothermic reduction is the preferred method of treatment of electric arc furnace (EAF) dust (listed hazardous waste, K061). The process maximizes the recovery of recyclable constituents by concurrent production of saleable zinc metal (directly condensed from the furnace off-gases), an innocuous, disposable iron oxide-rich slag, and some metallic iron. Results of a mineralogical investigation of a foaming slag produced during selective carbothermic reduction treatment of EAF dusts are presented. Wiistite and tricalcium silicate were identified by reflected light microscopy as the primary crystalline phases contained in a glassy matrix, but this technique failed to reveal any solid phases that could have significantly contributed to foam stability. It was concluded therefore, that the foam had been unstable, and had been primarily generated by copious gas evolution associated with the sudden reduction of the slag by an inadvertent addition of carbonaceous reductant. This is consistent with the susceptibility to foaming, when subjected to sudden excesses of carbon, of the slags produced by selective carbothermic reduction, because they still contain unreduced components such as iron oxide.

Jan 1, 1994

By H. C. Cooke

Those who have followed the geological developments in connection with the copper deposits of Quebec will recall that on many properties the sulphide bodies occur as replacements of fault breccias or tuff breccias, and exhibit a pronounced distaste for the more massive lavas. At the same time the rocks around the ore-bodies are profundly altered, first by addition of silica and sericite, later by conversion of these minerals into chlorite. It has been known for some years that at the Amulet and Waite-Ackerman Montgomery mines these conditions do not prevail. At both mines the ore-bodies are replacements of massive lavas, and at the Amulet they are associated with a very peculiar rock christened ?spotted dog', or 'dalmatianite'. Accordingly, when in 1929 the writer had the opportunity to make a further examination of these properties, two problems presented themselves for solution. The first was to determine, if possible, the conditions under which massive lava, rather than breccia, is replaced by the sulphide masses; the second, to find out the exact nature of dalmatianite and its relations to the sulphide bodies. The first of these problems is believed to have been solved; the second has been found very complex, and will require further work before it is satisfactorily settled.

Jan 1, 1930

By I. Peerawattuk

Growing demand for Li-based battery technologies is leading to an unprecedented growth in the lithium industry. Although innovation in battery technologies has pushed lithium into the spotlight, lithium was not always known for its application in batteries. The primary use of lithium—prior to the introduction of commercial lithium-ion batteries in the early 2000s—was in the ceramics, glass, grease, and the medical industry. Before being converted into usable forms, lithium products must be upgraded from the raw material. Processes for recovering lithium may involve: thermal treatment, water leaching, solar evaporation, ion exchange, carbonation, and electrodialysis. Presented, is a historical review of lithium applications and the different techniques of converting lithium-rich minerals and brines into usable products with additional discussion on future lithium extraction processes.

By Zhigang Liang

A carbon free precast block was prepared by using high-alumina fused corundum as aggregate and fused magnesia, and ultra-fine Al2O3 and ultra-fine SiO2 powders as matrix materials. A small linear expansion for the precast block was achieved through spinel formation from the reaction of MgO with Al2O3. The precast block showed a lower apparent porosity, higher hot modulus of rupture and better slag corrosion resistance compared to the traditional Al2O3-MgO-C brick. Moreover, the practical application of the precast block to the ladle lining proved it to possess a better thermal insulation which could effectively prevent the temperature drop of molten steel during the refining process. It can be predicted that the carbon free precast block could possibly be accepted as a new type of ladle lining material for the production of low-carbon and ultra-low-carbon steel.

Jan 1, 2009

By He De-wen

Based on the principle of life cycle assessment (LCA), municipal solid waste management (MSWM) was analyzed by life cycle inventory method. According to the system expansion and substitution method, the content and frame of life cycle analysis is summarized and applied to municipal solid waste. On the basic of feasibility research of life cycle analysis on MSWM, the paper put forwards complete and concrete ?three changes? measures under life cycle analysis on MSWM. Some aims of MSWM can be achieved under above conditions of LCA on MSWM: to improve the current system efficiency of MSWM; to enhance the serve quality of MSWM, to increase recycle garbage from MSW; to reduce waste amount and reach minimization and innocuity aim of MSWM; to help the departments of MSWM to get over all difficulties to realize their ideal goals.

Jan 1, 2009

By John J. Sammarco

This U.S. Bureau of Mines report describes the research effort and results for a computer-assisted appendage control system of a Joy 14CM continuous mining machine. The cutter head (shear), gathering head, conveyor, and stabilizer jack are the appendages. Positional control of each appendage is accomplished by specifying the desired position to the appendage control computer, which uses appendage position sensor data. Appendage movement is actuated until the desired position is attained as determined by control algorithms. A description of the sensors, mechanical and electrical interfaces, data acquisition and control (DAC) system, experimental method to determine appendage response characteristics (range of motion, start and stop delay times, and movement rates), and their application to the position control loop algorithms are presented. Also, the test results for the shear in an unloaded (free space) and loaded (cutting) condition of the shear are presented.

Jan 1, 1991

By Douglas D. Reynolds

Intense vibration can be transmitted to the hands and arms of workers who use hand-held percussive or vibrating devices, tools, and work pieces. Continued habitual exposure to vibration directed to the hands can cause patterns of various symptoms associated with hand-arm vibration syndrome (HVAS). The International Organization for Standardization (ISO) first published ISO 5349 in 1986.3 This standard specified methods for measuring and evaluating vibration directed into the hands from hand-held vibrating devices, tools, and work pieces. The American National Standards Institute (ANSI) published ANSI S3.34 the same year.1 This standard was modeled after ISO 5349-1986 and specified methods for assessing exposure to hand-arm vibration. The Parliament of the European Union has issued the European Union Human Vibration Directive-2002/44/EC, which specifies vibration daily exposure action values (DEAV) of 2.5 m/s2 and daily exposure limit values (DELV) of 5.0 m/s2. These values have generally been accepted by medical experts, scientists, and engineers in governmental agencies, research institutions, and industry in the USA and other countries.2 When they are achieved, they will reduce the potential for the development of symptoms related to HAVS among workers exposed to hand-arm vibration. Significant improvements in measurement and analysis instrumentation, miniature and subminiature accelerometers, and medical diagnostic and assessment protocols have being introduced since 1986 when ANSI S3.34 was first published. In response to these improvements and the introduction of the EU Human Vibration Directive, ANSI Working Group S2.39 developed the revision to ANSI S3.34, which has now been published as ANSI S2.70-2006.2 Method ANSI S2.70 specifies the use of the hand-arm vibration measurement procedures outlined in ISO 5349, Parts 1 and 2.2,4,5 It requires the measurement of ISO frequency-weighted acceleration values in three mutually orthogonal axes of vibration. These values are then vectorially added to obtain the vibration total value, ahv: [ ] where ahwx, ahwy, and ahwz are the measured r.m.s. ISO frequency-weighted acceleration values in the x, y, and z directions, respectively. If multiple vibration exposure events are experienced during a work day, the overall vibration total value is obtained from: [ ] where ahvi is the vibration total value of the ith operation, Ti is time duration in hours of the ith operation, n is the total number of operations, and T is total time in hours associated with the n

Jan 6, 2006

By J. H. East

THE RIFLE, COLO., oil-shale project of the Bureau of Mines was a facet of the re-search and development activities conducted under the Synthetic Liquid Fuels Act (Public Law 78-290) of April 5, 1944. The principal objectives were to devise efficient methods to mine and retort oil shale and to refine shale oil into usable products, at a total cost low enough that shale oil could supplement the domestic supply of petroleum at competitive prices. The Rifle project included three major divisions: (1) Mining, (2) retorting, and (3) refining. The major functions of the mining program were to supply oil shale to the retorts, to devise mining procedures, and to develop an under-ground-mining method by which oil shale could be produced safely at an unusually low cost per ton. The selected mining procedures and direct mining costs were demonstrated by sustained test runs.

Jan 1, 1964

By J. V. Atwood

The U.S. Bureau of Mines has developed a novel Double Membrane Electrolytic Cell (DMEC) that exhibits unique features for recycling contaminated metals and metal alloys. The DMEC incorporates two anionic ion exchange membranes, separating anodic and cathodic regions of the cell. The ion exchange membranes prevent significant transport of unwanted cationic impurities to the catholyte from the impure anolyte while the anion/cation balance in cell compartments is maintained through the free movement of anions between compartments. The membrane barrier makes it possible to electro refine highly contaminated materials or to electrowin from solution while utilizing alternate anode reactions. Sinceanolyte and catholyte cross contamination has been eliminated, premium cathode products are produced. The DMEC has been tested at bench, pilot, and commercial scales. Configuration of the DMEC, cell operation, scale, up efforts, and significant design factors are discussed. Two separate recycling investigations utilizing DMEC technology are presented. The first investigation examines recovery of high purity cobalt and nickel from severely contaminated super aIloy scrap. The second involves? upgrading contaminated cobalt in the U.S. Government's National Defense Stockpile. Capital and operating costs for both potential applications are presented.

Jan 1, 1995

This Workshop was held at the Doubletree Inn, Seattle, Washington from September 26 to 28, 1997. Run under the auspices of the Deep Foundations Institute (DFI), it was co-funded by the newly formed Japanese Association of Micropiles (JAMP), and the Federal Highway Administration (FHWA). The Workshop was jointly organized and facilitated by Fujita Research Corporation and ECO Geosystems, Inc., with close support by Donald B. Murphy Contractors, Inc. DFI kindly consented to publish these Proceedings. As is clear from the list of attendees, 42 specially invited engineers from all aspects of micropile technology were present, representing Japanese, European and American practice. This proved to be a most friendly and interactive group of people, who freely exchanged ideas, views and close comradeship, not only during the technical sessions, but (and especially!) during the numerous social events. Perhaps the best illustration of this came in Day 2 when the attendees were divided into five competing teams, each comprising representatives from the different geographic groupings. These teams had to quickly devise solutions to two technical problems (using standard data previously provided. A team of "referees" (who also acted as "coaches") later determined the most apposite response, based on constructability design concept, cost, schedule and so on. Not only were the winning team very liberal in distributing the prize (vintage California champagne) among themselves, but the whole Workshop soon benefited from their generous division of the spoils of victory.

Jan 1, 1997

By George E. Roberts

THE gains of society from the state of primitive conditions in the past to the standard of living which prevails in the advanced countries today have been accomplished mainly by the increasing productive capacity of the population under the leadership and services of the engineer. Without improvements in the arts and industries the growth of population tends to place succeeding generations always at a disadvantage. In this country we have been exploiting with reckless prodigality a wealth of soil and minerals and timber that has been in preparation for thousands of years. We know that the prices of all national products have been advancing, and were on a rising scale even before the phenomenal increases resulting from the war. Over against this depletion of natural wealth we have the influence of improvements made in the methods of production and distribution-and the accumulation of wealth in the form of productive equipment. The net result of these opposing influences determines whether society moves forward or backward.

Jan 1, 1926

By Marcie A. Greenberg

The Fence Lake Project is located in the Salt Lake coal field, an extension of the San Juan Basin. Geologic formations exposed in the Project area range in age from late Cretaceous to Quaternary. Coal is encountered in the Moreno Hill Formation (upper Cretaceous). Salt River Project (SRP) followed the basic textbook approach for the exploration, regional appraisal, detailed reconnaissance, detailed surface appraisal and three dimensional sampling (physical exploration). SRP is exploring this property as a potential fuel source for the Coronado Generating Station. Therefore, for the physical exploration stage, the quality sampling program was designed from a utility company viewpoint to determine possible impacts to the Station. Exploration drilling was completed in spring, 1982; September, 1982, and summer, 1984. Engineering, environmental, and land acquisition studies were added in the Summer, 1984 Program to more closely evaluate the potential Fence Lake Project coal supply option for the Coronado Generating Station. Studies, including drilling, are ongoing-at this time.

Jan 1, 1984

By C Roche, G M. Mudd

The Morobe Province of central Papua New Guinea (PNG) has been mined for gold for nearly a century, although it is only in the past decade that large-scale modern mining commenced. The Hidden Valley gold-silver project began construction in mid-2006 and production by August 2009, and is located in the mountains above Wau in the headwaters of the Watut River. The mine is owned and operated by the Morobe Mining Joint Venture (MMJV), which also owns the Wafi-Golpu project, comprising the Wafi gold deposit and Golpu copper-gold deposit, situated in the Watut River Valley. Together they represent a potential mine of the scale of Ok Tedi or Bougainville or bigger. The MMJV is owned in equal shares by Newcrest Mining from Australia and Harmony Gold from South Africa. Although Hidden Valley was the first large-scale mine in PNG to engineer and build a tailings storage facility, poor environmental management during construction and early operations led to significant erosion of waste rock and sedimentation impacts throughout the ~200 km length of the Watut River. Since then, substantial efforts have been made to improve environmental management, especially waste rock placement and storage and water quality management. While the impacts from the Hidden Valley project appear to be reducing, the saga has heightened concerns by many along the Watut River and across PNG about ongoing impacts from mining.This paper presents the results of an ongoing project in the Morobe Province conducted by the Mineral Policy Institute examining the historical, current and future impacts of mining, including community views, social and environmental impacts and the monitoring and regulation of mining. Overall, there is a clear need to more fully integrate social and environmental issues into life-of-mine planning and go above and beyond regulatory requirements. In this way, some of the lessons learnt – by the community, MMJV and government – can be incorporated before, during and long after mining.CITATION:Mudd, G M and Roche, C, ?2014. Mining in Morobe, Papua New Guinea – impacts, assurance and self-determination, in Proceedings Life-of-Mine 2014 , pp 313–336 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By Kirk Ellison, Sherif Elfass, Ramin Motamed, Kevin V. Stanton

"The determination of accurate load transfer curves are essential for estimating deep foundation loadsettlement response using t-z style analyses. While recently developed semi-empirical methods from Ashour et al. (2010) and Ashour & Helal (2012) have shown promise in preliminary studies, they have not yet been thoroughly benchmarked against a more widely accepted approach. To address this issue, these recent procedures are implemented in the computer program CGI-DFSAP to predict the results of four Osterberg-cell (O-Cell) load tests. These predictions are compared to outcomes obtained following the recommendations from Reese & O’Neill (1988) for t-z analyses of drilled shafts in sand and clay which are carried out with the program TZ-PILE. Overall, the results suggest that the new approach offers improved accuracy regarding predictions of drilled shaft response to axial loading.INTRODUCTIONThe behavior of axially loaded deep foundations is often analyzed using a technique known as the t-z method. In this method, deep foundation elements are broken into multiple segments which are supported by discrete nonlinear springs to capture the contribution of both side-friction (t-z springs) and end-bearing (Q-z springs). Hence, the t-z and Q-z relationships dictate the predicted load-settlement response. A number of different approaches have been developed to estimate load-transfer curves with some relying solely on empirical data from laboratory and field experiments (i.e. Coyle & Reese, 1966; Vijayvergiya, 1977) and others based mainly on analytical frameworks (i.e. Kraft et al., 1981; Randolph, 1994). Reese & O’Neill (1988) provide recommendations which are widely used for developing t-z and Q-z curves for analyzing drilled shafts. This method is hereafter referred to as Method 1 (M1). It should be noted that these empirically derived relationships are only applicable for problems associated with drilled shafts and are therefore not appropriate for developing load-transfer curves for other types of deep foundations (i.e. driven piles). This is because of the difference in the frictional resistance which can be developed between a circular concrete-soil interface as opposed to that of other materials (i.e. steel) and/or different cross sectional geometries.The M1 load-transfer curves form the basis for the t-z analysis of drilled shafts implemented in the computer program TZ-PILE (Ensoft, 2014). In light of this, TZ-PILE is employed herein as a reference to compare against the capabilities of another method of implementing t-z style analyses. This method is based on a semi-empirical framework for soil behavior developed by Norris (1986) and is implemented using the program CGI-DFSAP (Computers & GeoEngineering Inc., 2011). More information concerning this approach, hereafter referred to as Method 2 (M2), is given in subsequent sections."

Jan 1, 2017

By J. A. du Plessis, C. Dorfling

Selenium, tellurium and other precious metals (OPMs, namely Rh, Ru and Ir) dissolve in the final leaching stage of base metal refineries. Se and Te are typically removed from the copper sulphate leach solution by precipitation with sulphurous acid. Recovery of dissolved OPMs is desirable because it will reduce OPM inventory and losses. Thiourea is an effective OPM precipitation reagent, but yields insufficient Te removal. Copper is known to enhance Te precipitation when using sulphurous acid as precipitation reagent. The primary objective of this project was to evaluate whether simultaneous precipitation of Se, Te and OPMs using thiourea with metallic copper as precipitation reagents is possible. Batch precipitation tests were performed to evaluate the effect of temperature (50 – 70°C), thiourea addition (160 – 430% excess) and copper addition (2 – 8 g/L) on Se, Te and OPM precipitation. Increasing the temperature from 50°C to 70°C resulted in an average increase of 55.6 percentage points for Se precipitation and 13.5 – 23.5 percentage points for OPM precipitation. The copper addition did not have a significant impact on the precipitation behaviour. Increasing the thiourea addition increased the precipitation of Se and Te, especially when the copper addition was low; Rh and Ru precipitation also increased with up to 10 and 12 percentage points, respectively. Despite these observations, the precipitation of Se was significantly faster when no thiourea was added. It is not currently clear why thiourea appears to inhibit the Se precipitation by reaction with metallic copper. In general, Te precipitation was low (less than 30%) at the conditions investigated. Simultaneous precipitation of Se, Te and OPMs at temperatures below 80°C does not appear to be a viable option; a multiple stage operation for sequential removal of Se and Te with copper followed by OPM precipitation with thiourea would be required.

Jan 1, 2016

By L. Nahai

In two decades Turkey has emerged from the debacle of the Ottoman Empire to become one of the most modern nations in the Middle East. The numerous achievements of this period were remarkable in that they affected human and social, as well as economic, fields. Most of this progress was achieved by Turkey's unaided efforts and the utilization of domestic resources; however, since 1948 various United States aid programs3/ have made significant contributions to increased agricultural and industrial output. Turkey's singleness of purpose in favor of a strong, independent, and prosperous republic has evoked universal admiration and encouraged the hope of stability in the Middle East. Much of the development of the Turkish economy to date has been fostered by the State; however, with growing strength the leaders in 1950 considered the time appro¬priate to relax the nationalistic economic policy and permit private enterprise to play a larger role in increasing domestic output and raising the tempo of industrialization. In pursuance! Of this policy, laws encouraging investment of foreign capital in Turkey and others stimulating development of mining and petroleum enterprises were enacted in 1954. This new legislation, plus the cooperative attitude of the Turkish Government, have encouraged wide interest in the mineral resources of the country.

Jan 1, 1958