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By Tassos Grammatikopoulos, Gary Pearse, Massoud Aghamirian, Charlotte Forstner, Stephen Mackie

"SGS Minerals Services (Lakefield, Ontario site) has conducted a number of developmental and pilot programs that examined methods for the beneficiation, extraction and recovery of lithium from a variety of spodumene containing hard rock sources. An overview of the beneficiation programs is presented separately by Aghamirian, Mohns, Grammatikopoulos, Imeson & Pearse (2011). The focus of this discussion will be the hydrometallurgical steps involved in producing a high grade lithium carbonate (Li2CO3) sample from the spodumene concentrate. SGS has applied the standard Li2CO3 hydrometallurgical flow sheet to a number of spodumene concentrates and has determined that all of these samples respond in a similar manner to the process and produce a final product having a Li2CO3 grade of >99.5%. The standard process is sufficiently robust to accommodate the observed variability in the concentrates that have been tested. Advantage of one spodumene deposit over another will thus be gained through process optimization and innovation. Optimization at the beneficiation stage and at the hydrometallurgical stage must be considered. Some aspects of the process optimization of the hydrometallurgical flow sheet will be presented.INTRODUCTION The current activity in the exploration, development, and mining of lithium based minerals is due in large part to the key role that this metal plays in the rechargeable battery industry (U.S. Geological Survey, 2011). Lithium battery technologies are widely applied in a range of portable electronic consumer products. The expanding development and production of hybrid and fully electric vehicles has contributed to the increased interest in finding and developing new lithium sources in order to meet the expected demand from the lithium battery industry. Lithium may be sourced from continental brines (sub-surface salars), hard rock minerals (pegmatite, spodumene), hectorite clay deposits, geothermal brines and oilfield brines. Currently the majority of the lithium products are produced from Li brines. The four major lithium producing countries are Chile, Australia, China, and Argentina (U.S. Geological Survey, 2009; Roskill, 2009). These countries accounted for 97.6% of the total lithium produced in 2010."

Jan 1, 2012

There is a lack of information concerning the movements of water on the continental shelf, particularly with regard to data obtained regularly over significant periods of time. The Horace Lamb Centre for Oceanographic Research has recently deployed data acquisition systems on the sea bed off the coast of South Australia to record tides, swell, and ocean temperatures. Some of these early records are described. The swell data are pertinent to future offshore operations with drilling rigs, barges, and other equipment, while the temperature variations give evidence of significant bottom currents, apart from those due to swell.

Jan 1, 1971

By Tiezheng Li

Keywords: Laminate Composites; Mechanical Behavior; Damage Evolution The mechanical performance of Ti-6-4-Al3Ti metal-intermetallic laminate (MIL) composites synthesized by a reactive foil sintering technique was evaluated. Crack morphology of untested Ti-6-4-Al3Ti MIL composites has been characterized by optical microscopy. Mechanical tests were performed on Ti-Al3Ti metal-intermetallic laminate (MIL) composites and pure Al3Ti, and the principal mechanisms of damage initiation and accumulation were identified experimentally. The elastic properties and anisotropy of the laminates were calculated and successfully compared with Resonant Ultrasonic Spectroscopy (RUS) measurements. The effect of residual stress on the fracture toughness of the Ti-6-4-Al3Ti MIL composites was analyzed.

Jan 1, 2005

Despite the wealth of information available on phase equilibria of oxide systems there remainmany gaps and inconsistencies in our knowledge base. From an industry perspective there is anongoing need to adequately describe the phase chemistry of slag systems in order to optimizeprocess performance and improve productivity. Since this chemical behaviour cannot be predictedfrom first principles it follows there is also an ongoing need for accurate experimental data. The advances made in recent years in the capabilities of sophisticated analytical and measurement equipment have made it possible to develop new experimental techniques for the direct determination of phase equilibria in low order and complex multi-component slag systems. In addition the development of powerful computer modelling tools makes it possible to provide more comprehensive descriptions of the phase chemistry, to present the information in a range of perspectives, and to critically analyse the various types of related thermodynamic and structural information available. This review provides an overview of the types of information that can be used to determine phase equilibria in slags systems, analyses the influence of uncertainty and the relative importance of these types of data, and describes the advantages and limitations of the various experimental techniques that can be employed to obtain this information. Examples of recent studies are provided that demonstrate how an integrated approach to the determination of phase equilibria in complex systems, involving the use of targeted experimental studies and systematic thermodynamic model development, can lead to a better utilization of our current research capabilities and resources and more accurate descriptions of these systems. Keywords: slags, phase equilibria, experimental techniques

Jan 1, 2004

By S. J. Schatzel, W. P. Diamond

High methane emissions originating from the active face areas and from the fractured formations overlying and underlying the mined coalbed can adversely affect both safety and productivity in underground coal mines. Since ventilation alone may not be sufficient to control the methane levels in the longwall mining environment, gob gas ventholes have become a standard supplementary methane control option in many mines. As mines progress into deeper and gassier coalbeds, or as longwall panel size increases, ventilation and gob gas ventholes together may not be sufficient to maintain methane levels within statutory limits. To decrease the risk associated with methane emissions under these circumstances, in-seam horizontal methane drainage is often used to reduce the gas content of the coalbed prior to mining. Horizontal methane drainage borehole completion designs, drilling strategies, and degasification lead times may need to be adjusted for site-specific conditions due to mine design, geology, and the gas content of the coalbed. This study investigates different horizontal methane drainage borehole patterns, borehole lengths, and degasification times prior to and during panel extraction to evaluate their effectiveness in reducing methane emissions using a "dynamic" 3D reservoir modeling of a 38 1-m wide longwall panel operating in the Pittsburgh coalbed. Results of this study showed that dual and tri-lateral boreholes are more effective in decreasing emissions and in shielding the entries compared to fewer shorter, cross-panel, horizontal boreholes parallel to the longwall face. Modeling results showed that after 12 months of pre-mining methane drainage, the average longwall face emission rates can be reduced by as much as 10.3 m3/min and 6.8 m3/min using tri- and dual-lateral boreholes, respectively. It was also shown that if pre-mining methane drainage time is short, it is important to continue methane drainage during the panel extraction to maximize reductions in longwall face emissions since additional face emission reductions achieved during this period can be comparable to pre-mining degasification.

By Kenneth Eltschlager, Jim Ratcliff, Michael Mann, Edward Sheehan

The Appalachian Blaster Certification Delegation initiated a study to compare the consistency of measurements from blasting seismographs. Six blasts were monitored at surface coal mines in West Virginia, Maryland, and Ohio. A total of seven different makes were deployed during the tests, with as many as seven models from five different manufacturers compared during any one blast. Great care was taken to bury the geophones in identical fashion. The variations in seismograph readings were compared to the International Society of Explosives Engineers’ Performance Specifications for Blasting Seismographs. Between 4 and 125 Hertz, the ground vibration amplitudes should be within ±5% and airblast amplitudes should be ±1 decibel. For each of the three mutually perpendicular ground vibration channels and the acoustic channel, the median value of all the units was used as a baseline for comparison. The six blasts monitored had median peak particle velocities ranging from 0.42 to 3.47 inches per second (in/s) (10.7 – 88.1 mm/s) and median airblasts ranging from 124 to 135 decibels (dB). There were 46 seismograph recordings for the six blasts. Eighteen (39%) of the 46 maximum peak particle velocities varied more than ±5% from the median. A total of 138 (3 × 46) component particle velocities were recorded, with 50 (36%) of the readings varying more than ±5% from the median. For airblast comparison, 43 recordings were obtained, with seven (16%) varying more than ±1 dB of the median. Variances may be attributable to blasting seismograph differences, variations in field deployment, and relative locations of the geophones. Full waveform seismic and acoustic overlays for individual blasts showed encouraging conformity with some slight anomalies

Jan 1, 2015

By Ulrich Paschedag

The WESTFALIA group of companies developer and manufactures underground mining machinery for complete high-performance longwalls. WESTFALIA uses a state of the art electrohydraulic system as the most important component for the realisation of today's fully automated plow or shearer longwall. The shield control unit (SCU) allows maximum custom designed software flexiblity as well as maximum hardware reliability. The master control unit (MCU) monitors shield support data as well as the plow/shearer position. By using an industry standard PC in an explosion-proof box with an intransically safe keyboard nearly unlimited software capabilities can be obtained with inexpensive hardware. Among various other modes of operation this MCU allows the monitoring and recording of data which can be transmitted to a surface computer. Production and operational adjustments can be made by the mine management based on the MCU information. Statistical analysis of the distribution of roof pressure under various conditions is also possible. The WESTFALIA automation system PM-4 gives the operator maximum flexibility and helps the mine management to run their longwall more efficiently and safely.

Jan 1, 1994

This paper examines the issues involved in the technical audit and valuation of exploration prospects. Certain methodologies are more appropriate to use depending upon whether the mineral property valuation is of an exploration area, a project under development, or an operating mine. Valuation approaches that are reviewed include the Multiple of Exploration Expenditure, Joint Venture Terms, Rules of Thumb, and particularly the Kilburn Rating Method. The DCF/NPV Financial Simulation Method, even modified by the use of Expected Values, is not considered appropriate for valuing exploration prospects. The choice of the most appropriate methodology and its successful application depends primarily upon the amount of reliable input data available and, more importantly, the experience and judgement of the valuer. It must be remembered that all valuations are time and circumstance specific and will be generally subject to revision as more data becomes available.

Jan 1, 1993

By I M. Turnbull

QMAP (the Quarter Million Mapping Programme, 1:250 000 scale) is a geological mapping programme which will build a digital geological database of the whole country and publish maps and books to document it. The programme was established in 1993, following a recommendation by a review panel appointed by the Ministry of Research, Science & Technology, and is funded by the government, from the Public Good Science Fund. The relevance and fundamental value of QMAP lies in the greatly improved geological knowledge it will provide for researchers and other end-users of geological information.   QMAP research involves assessment of previous work, field and laboratory investigations in key areas, and data storage, manipulation and publication using Geographic Information Systems (GIS) computer technology. The QMAP digital database of New Zealand geology will be completed by 2006, as will the series of 21 full colour printed geological maps and accompanying explanatory texts. Two are already completed and published (Kaitaia and Dunedin), and six other projects are well advanced.   QMAP information will also be available in digital form. Next year we hope to expand the scope of the programme to cover the reconciling and linking of many other earth science databases to QMAP, because we believe this will create a powerful research tool. The intention is to develop internet access to the databases, to make the information publicly available.

Jan 1, 1997

By G. W. Jones

Fires in anthracite refuse banks are troublesome and may become exceedingly costly to combat. Instances are known in which refuse-bank fires have grown to such magnitude that entire mining properties have been endangered. In one instance4/ a refuse-bank fire cost the mine management several hundred thousand dollars to extinguish. The exact number of fires formerly existing or now active in the anthracite region of Pennsylvania is not known. There are hundreds of anthracite refuse banks in this region, some very high and large in area, that have never caught firs, although a few are over 50 years old. This would indicate that spontaneous ignition of the material in these banks is improbable, a conclusion confirmed by recent laboratory research.

Jan 1, 1939

By G. W. Jones

Fires in anthracite refuse banks are troublesome and may become exceedingly costly to combat. Instances are known in which refuse-bank fires have grown to such magnitude that entire mining properties have been endangered. In one instance4/ a refuse-bank fire cost the mine management several hundred thousand dollars to extinguish. The exact number of fires formerly existing or now active in the anthracite region of Pennsylvania is not known, There are hundreds of anthracite refuse banks in this region, some very high and large in area, that have never caught fire, although a few are over 50 years old. This would indicate that spontaneous ignition of the material in these banks is improbable, a conclusion confirmed by recent laboratory research.

Jan 1, 1939

By Khamis Y. Haramy

This Bureau of Mines paper describes the use of the borehole shear tester (BST) In mines. Assembly and procedure sections explain how the equipment is assembled and used properly. Schematics of the BST, limitations, test hole specifications, data recording and calculations are all explained briefly, and an example of the data collecting and calculations is given to assist understanding.

Jan 1, 1981

The purpose of this report is to describe the work accomplished by Mine Safety Appliances Company under Contract No. H0110845. This contract required the design, installation and testing of a permissible mine surveillance and communication system for the USBM Bruceton experimental mine facility. While much of the design and operational detail of this system can be drawn from the instruction manuals delivered with the equipment, some of it will be repeated here in Volume I for the sake of clarity, but the principal objective will be to report on overall system and subsystem performance and to suggest design alternatives for future consideration. Details of the overall system design will be found in Volume II of this report.

Jan 1, 1973

By Arel B. McMahan

The U.S. Bureau of Mines investigated 21 mines, prospects, and mineralized sites in and adjacent to a 38,713-acre portion of the 255,058-acre Kingston Range Wilderness Study Area in 1983. The study area is 35 miles north of Baker, CA in the Mojave Desert. Mineral deposits in and adjacent to the study area are in altered carbonate rocks intruded by diabase sills near monzonite porphyry contacts. Monzonite porphyry forms the core of the Kingston Range and underlies about 70 percent of the study area. Sedimentary carbonate rocks are exposed in bands on the north and east boundaries and as isolated roof pendants in the southeastern portion of the study area.

Jan 1, 1986

By Frank Parrish

History and performance data of 17 water-injection projects in Cooke and Grayson Counties in north Texas are presented for the purpose of studying and comparing operating practices and oil-recovery techniques. Water is injected into Strawn and Canyon sands of Pennsylvanian age. The principal formation flooded is the Strawn, which ranges in depth from 725 to 6,900 ft in the projects covered. Estimated ultimate recoveries range as follows: Primary, 22 to 494 bbl per acre ft; and secondary; 63 to 296 bbl per acre ft. These figures represent the following percentages of original oil in place: Primary, 10 to 46 pct; and secondary, 8 to 23 pct. Shallower projects; 725 to 1,500 ft in depth, had higher average primary and secondary recoveries than did deeper projects. Crude-oil gravity, which ranges from 20° to 45° API, was not relatable to yield of secondary recovery oil. Analysis of the data indicates that five-spot injection patterns will yield the highest percentage of oil remaining at start of flooding; that is, 28.8 pct for five-spot injection patterns, compared with 20.8 pct for line-drive patterns and 11.6 pct for random patterns. Waterflooding in this area appears to be very successful. Secondary recoveries of most projects are expected to nearly equal primary recoveries.

Jan 1, 1963

By Dr. Peter J. Conroy

The current study is part of the U.S. Department of Energy's (DOE) on-going subsidence research program. The long-term objective of the DOE program is to develop analytical methods of subsidence prediction applicable over a broad range of geologic and mining conditions encountered in the United States. The DOE currently has several contracts in progress to develop a sound data base that can be used in the development of predictive models. Dames & Moore is currently under contract to the DOE to collect and analyze detailed subsidence and hydrologic data from a coal mine employing longwall mining methods in the Eastern Coal Province. Work under Contract No. DE-AC22-80PC 30335 began in October of 1980 and will continue through September of 1984. This paper summarizes the work that has been completed through September of 1981 and presents the results that have been achieved during this period. Technical difficulties encountered during both the installation and monitoring phases are discussed, and recommendations for future work are presented.

Jan 1, 1982

By Richard F. Hewlett

Engineers at the Bureau of Mines Denver Mining Research Center have been a research program investigating the theory and application of mine sampling. Part of this program is an investigation of the efficiency of sampling methods that involves development of sampling-method theory through simulating ore-deposit samples and assays, using - electronic digital computer. Theoretical developments are checked against actual ore-deposit sampling, assay, and production data by the commonly used polygonal and triangular methods of computing grade and tonnage of ore reserves. To speed the computing procedures, a program has been developed utilizing a medium-size digital computer for computing ore reserves by the polygonal method. This program calculates nine prismoids per minute at a total cost of $0.21 per prismoid. The complete program, written for an augmented IBM 650 computer, is described in detail; it can be used without change for computing ore reserves for a low-grade deposit. Modifications necessary to convert the program to compute ore reserves for virtually any other type of deposit or grouping of ore horizons also are given; however, the program is limited to using only vertical drill-hole data.

Jan 1, 1962

By Alla D. Mah

The need for more and better basic thermodynamic data for the oxides of many of the rare metals is evident to anyone who attempts thermodynamic calculations involving these substances. In continuation of a Bureau of Mines program to meet this need, this paper reports new experimental values of the heats of formation at 298.15° K. of the hexagonal crystalline variety of germanium dioxide and germanium dioxide glass. The values were obtained by means of combustion calorimetry and sodium hydroxide-solution calorimetry. The calorimetric results also made possible the derivation of values for the heat and entropy of fusion of hexagonal germanium dioxide at its melting point. The newly measured data were combined with previously known entropy and high-temperature heat content values to obtain heats and free energies of formation of germanium dioxide (in the hexagonal crystalline, glassy, and liquid states) over the temperature range from 298.15° to 2,000° K.

Jan 1, 1962

By B. J. Breen, C. S. Mogg

Considerable borehole investigation work has been completed at a proposed site at Sellafield in Cumbria, supplemented by seismic surveys, other geophysical sensing and geological mapping. The focussing of investigation on the rock mass itself will be achieved by means of the planned underground rock characterisation facility, giving access to depths of about 800 m in the strong, low-permeability basement rocks of the Borrowdale Volcanic Group. Characterisation work undertaken during the sinking phase and interaction with continuing surface-based exploration and monitoring should permit a firmer assessment of the long-term safety of a repository. Key considerations in the choice of a design for the repository include the waste handling method, underground inlet cell, underground vaults, vault environment and environmental effects

Aug 1, 1994

By W. K. Overbey

The Bureau of Mines conducted surface joint and stress measurements, airborne remote sensing imagery studies, compass-oriented borehole televiewer surveys, numerical simulation of fractured wells, and well productivity studies in a four-quadrangle study area of Ohio, to determine the effects of earth fracture systems on the deliverability of gas storage fields. The results of these studies indicate that much useful information about a gas storage reservoir can be obtained and put to practical use by studying--(1) oriented cores for fractures and directional permeability, (2) orientation of induced hydraulic fractures for alignment of well patterns, and (3) aerial photos and multispectral scanner imagery for general surface geology comparison and to determine if some, development patterns can be generated by such results. The absence of known tectonic elements associated with flat-lying sediments, such as faults or fracture zones that can be seen on the surface, indicates that the use of remote sensors such as radar or aerial photography is not likely to be useful in picking well locations for drilling. Studies similar to those discussed here should be conducted in gently folded and strongly folded sedimentary formation areas to determine if the increased knowledge of earth fracture systems under these conditions might be beneficial in gasfield and gas storage reservoir development.

Jan 1, 1974