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By James L. Ash

This report contains the results of a technical and economic evaluation of conceptual systems for the underground mining, rubblization, and in situ retorting of deep oil shale deposits. Study efforts were first directed towards evaluation of the applicable geology, associated minerals, rock mechanics, in situ retorting, access mining, ventilation, rubblization, safety, and environmental impact factors. Conceptual systems were synthesized and then evaluated against these factors from both a technical and limited economic viewpoint. The results of these evaluations were then analyzed and, based upon this analysis, the following two systems were selected for further study: System II: Room and Pillar-Vertical Drill and Blast System IV: Tunnel Boring-Horizontal Ring Drill and Blast Due to the large number of variables to be considered, a computer program was developed and utilized to provide data for the cost trade-off studies and economic analysis. Results of the early computer runs indicated the value of the tool available? in the computer program and led to an extension in the contract to determine the sensitivity of the systems to several of the more apparent significant variables. These results in turn led to a refinement in the design assumptions and a better understanding of the technical and economic options available to an owner-operator of a Vertical Modified In Situ Shale Oil Extraction System. This report is submitted in fulfillment of the requirements of Contract Number 50241073 by Fenix & Scisson, Inc. to the Denver Mining Research Center, United States Department of the Interior, Bureau of Mines. Work was completed as of November, 1976.

Jan 1, 1976

By AIME AIME

PLANS for the Semi-centennial Meeting have almost reached completion, although in any undertaking of such magnitude a few changes are always to be expected at the last moment. As worked out up to the time of going to press, the program of the meeting is shown below. The headquarters will be the Irem Temple, in Wilkes-Barre.

Jan 1, 1921

By M. J. Papo, A. Muwila

Hercules? is a low nickel austenitic stainless steel developed at Mintek that has a typical composition of 9 wt% Mn, 0.05 wt% C, 2 wt% Ni, 0.25 wt% N and 16.5 wt% Cr. A more corrosion resistant version of Hercules? (Hercules? B) with 0.5 wt% Mo has also been developed. Potentiodynamic tests performed on Hercules? B in a 5 wt% sulphuric acid solution showed it to have improved corrosion resistance comparable to that of AISI 304. The effect of a varying Mn content on the corrosion resistance of Hercules? B has also been investigated and the results discussed in this paper. From the corrosion test results, it is clear that decreasing the Mn content of Hercules? B increased the corrosion rate while increasing it decreased the corrosion rate. KEYWORDS Austenitic stainless steel, %ferrite, molybdenum, manganese, nitrogen, electrochemical corrosion tests, potentiodynamic scans, microstructure, chemical analysis.

Jan 1, 2006

Recycling of Sludge from the Production of Manganese

Sep 13, 2010

By P. G. Killeen

Proper calibration of portable gammaray spectrometers and spectrometric logging equipment is essential if they are to be used for accurate quantitative determinations of radioelement concentrations. In the case of both types of equipment, it is necessary to determine the system calibration constants (stripping factors and sensitivities). In the case of borehole logging equipment, it is further necessary to determine the system response characteristics if the data are to be computer processed to improve the accuracy and resolution of the logs. Facilities are now available near Ottawa for the complete calibration of portable gamma-ray spectrometers and spectrometric logging equipment, in addition to already existing facilities for calibrating airborne gamma-ray spectrometers. Limited additional facilities are also available or planned in several other areas of Canada.

Jan 1, 1978

By Ziyad Abunada, David O’Connor, Abir Al-Tabbaa

"Abstract Contaminated land remediation using soil mix technology (SMT) is a relatively recent development which has been shown to be a cost effective and versatile system with numerous environmental advantages over other remediation techniques. The added complexities and variability associated with contaminated sites has escalated the need for field trials, field monitoring and specific QC measures to be undertaken for this setting and was the rationale behind project SMiRT (Soil Mix Remediation Technology). The main aim of project SMiRT was field validation, testing and assessment to provide stakeholder confidence in SMT and increase its uptake for land remediation in the UK. The field trials involved the treatment of 800 m3 of soil, through applying six different remediation techniques with four different SMT systems and introducing over thirty binders and binder compositions with a range of installation methodologies. Various issues were faced during the installation process and which were addressed on site. This paper presents some aspects of early age field observations, field monitoring, in-situ testing, coring and laboratory testing of cored samples and highlights some lessons learnt, providing valuable information on the issues that need to be addressed for this application of SMT.IntroductionAlthough soil mix technology (SMT) was developed in the 1960s in Japan and Sweden for geotechnical applications, its potential in geo-environmental applications became evident more recently the 1980s in the US and in the 1990s in Europe, having since increased to provide a range of remediation systems (Al-Tabbaa and Evans, 2003; Al-Tabbaa et al., 2011). The most common applications to date have been (a) the construction of low permeability containment walls or cut-off walls to contain a contaminated site; (b) stabilisation/solidification (S/S) treatment, with cementitious binders, for physical and chemical encapsulation of contaminants in soils and (c) the installation of permeable reactive barriers (RPBs), which are permeable walls that intercept the groundwater flow and remove contaminants from it, by mixing special additives with the native soil. Contaminated land remediation using SMT is a cost effective and versatile approach with numerous technical and environmental advantages over other remediation techniques. These advantages include the use of simple and well established techniques and equipment, speedy implementation, applicability to sites of any size and to multiple contaminants, elimination of off-site disposal, low risk and low emissions. There is a lack of competing alternative technologies that offer the same level of versatility and economic, environmental and social benefits, under current environmental legislation constraints. In addition, most currently available contaminated land remediation techniques are only partially effective, and are relatively contaminant-specific. This makes SMT a promising and timely contender to lead the market place in offering a cost-effective, efficient and low risk solution to contaminated soil and groundwater remediation and has resulted in a range of recent innovations."

Jan 1, 2014

By D G. Randall, R Jivanji, J Nathoo, T Reddy

Paradoxically, the increased emphasis on water treatment in mining has generated a new problem û hypersaline brines. Currently brines are either disposed of into ash systems, lined evaporation ponds or hazardous waste sites. Evaporative crystallisation (EC) is an alternative, but the energy requirements can be prohibitive and the salt product is still a waste that must be disposed of. Eutectic freeze crystallisation (EFC) is an alternative technology that is capable of separating aqueous solutions into pure water (as ice) and pure, solidified solutes. It is highly energy efficient and does not depend on the introduction of any solvents. In addition, the simultaneous production of pure ice and potentially saleable pure salt(s) is a major advantage. Although EFC has been shown to be effective in separating a single salt and water, it is still in the early stages of being applied to the multi-component hypersaline brines that are typical of reverse osmosis retentates generated by mining and extractive metallurgy.This paper presents an EFC brine treatment protocol developed by the Crystallisation and Precipitation Unit at the University of Cape Town. The protocol incorporates brine analysis, thermodynamic modelling to establish which salts will freeze out and at which temperatures, followed by experimental studies to determine the kinetic parameters, such as nucleation temperatures, salt yields and crystal purity.Case studies showing the application of EFC for the purification of typical brines containing high levels of sodium, chlorine, sulfate and ammonia (Brine 1) and a mixture of sodium and magnesium sulfate (Brine 2) are covered. Modelling tools were applied to describe the phase behaviour of the multi-component saline systems under different process conditions. Experimental validation was carried out using synthetic brines of different (and increasingly complex) compositions. The results showed that EFC could be used to selectively recover the sodium as a sodium sulfate salt from both different brines. The simulation tools were useful in the analysis and understanding of the process.A preliminary economic analysis showed that the operating costs for EC were approximately nine times those for EFC, but the capital costs were much less- equipment for EC cost about half that of EFC. However, it is important to note that the capital cost calculations for EC are based on a technology that is already well established and with only relatively marginal future equipment cost savings expected. In contrast, EFC is a new technology, with significant future technology improvements expected.

Jan 1, 2009

By C. W. Goodale

TOMBSTONE, a name not exactly full of cheerful suggestion, has a great record as a mineral producer and a colorful history as a frontier mining camp. The only practical route to Tombstone in the early 80's was by way of San Francisco and Los Angeles. The Southern Pacific was building across Arizona, and a sleeper was attached to a construction and freight train at Los Angeles, and was trailed slowly across the Colorado Desert to Benson in the San Pedro Valley. Thence one staged 26 miles to Tombstone, which is located near the foot of a range of hills at an altitude of about 4500 ft.

Jan 1, 1925

By Derek J. Penrice

The Caltrain Downtown Extension (DTX) project will extend commuter and future statewide high-speed rail service into the Transbay Transit Center, which will be located in the business district in downtown San Francisco. The DTX project includes 1.5 miles of underground construction, comprising complex sections of mined and cut-and-cover tunnel. As part of the DTX preliminary engineering process, development of appropriate contracting practices, including contract packaging, procurement methods and contract terms for the underground construction, has been initiated. This paper provides a summary of the evaluations undertaken, preliminary conclusions reached, and proposed next steps to promote industry interest and maximize bid competition.

By J. R. Thoenen

The enormous and constantly increasing demand for limestone to supply a multitude of uses is a remarkable feature of the mineral industries. As approximately 130,000,000 tons of limestone are produced annually, it is not surprising that deposits at or near the surface are gradually being exhausted and that less advantageous supplies are being worked. Quarries are becoming deeper and wider year by year, and in many places the volume of overburden that must be removed to allow open-pit work has increased alarmingly. Quarrymen are also gradually learning how expensive it is to sort and clean stone from a deposit overlain by poor material. As such conditions confront the limestone industry, the natural tendency is to seek some modification in method whereby the handicaps of increasing cost may be met and overcome. Operators, some of them unwillingly, have been forced to conclude that underground work in drifts and tunnels is the most logical solution of the problem. The unwillingness of some is largely due to unfamiliarity with mining and to the unfounded fear that costs must increase and dangers multiply when mining is undertaken.

Jan 1, 1926

By A Kamkar-Rouhani

The paper describes a mineral potential mapping of gold and other base metals in Mahneshan area, Iran, using geographical information system (GIS), in which, the method of weights of evidence is used to combine spatial data obtained from different sources to make prediction for mineral potential. This is a quantitative tool for mineral resource mapping that can be used to delineate and predict favorable areas for further exploration by using the characteristics of known and similar mineral deposits. In accord with the descriptive model for gold and other base metal deposits, the spatial distribution of 20 known mineral occurrences was used. In addition, digital evidential maps were used in this study. The maps include maps of lithological units, faults and first derivative of total aeromagnetic data, remotely-sensing data of alteration and also geochemical evidential maps produced on the basis of the results of chemical analyses of samples taken from the stream sediments in the area, and analysed for Cu, Pb, Zn, Sb, As, Ag, Au, Ba and Hg elements. The binary maps were produced and then combined with the model of weights of evidence using 20 known mineral occurrences to obtain a final map of the favourable areas for further exploration of gold and other base metals in the study area. The final map is a predictive GIS model of the mineral deposits in the area. An interesting matter about the final predictive GIS model is that the faults are mainly located in favorable areas which possesses the most probability of mineralisation. Therefore, the faults in these areas have priority for further exploration of gold and others base metals.

Jan 1, 2005

By H. Tomlinson

"INTR0DUCTIONThis publication is a third of a series devoted to falls of roof and coal in coal mines of the Western States. It gives the results of examinations of the mines of the Rock Springs coal District of Sweetwater County, Wyo., which represent the principal coal beds therein and approximately 75 percent of total production of the State.A study was made of safety conditions at all the producing mines of the district and suggestions were offered the operators regarding methods and practices which would, in the opinion of the writer, provide additional safeguards to prevent accidents from falls of roof and coal.In presenting the subject, consideration must be given to such features as character of the coal beds, depth of cover. methods of mining, timbering practice, roof testing and supervision, and for comparative purposes to certain statistical matter bearing upon relation of accidents to their causes, tonnage produced, men employed, days worked, and lost days due to accidents during the 3—year period covered by this study.ACKNOWLEDGMENTSThe writer acknowledges the cooperation of the officials of the various coal companies, without whose assistance this work could not have been completed.F0UR REPRESENTATIVE COAL OPERATIONSThis report relates to four representative coal operations in the Rook Springs district of Sweetwater County, Wyo., which are referred to as mines A, B, C, and D. This group employs yearly an average of 993 men, representing 37 percent of the men in coal mines of the county, and has an average annual production of 1,484,373 tons, representing approximately 44 percent of the coal produced in the county. Figure 1 is a map of the Rook Springs coal district."

May 1, 1933

By E. H. Burroughs

This bulletin is the fifth in the series of petroleum bibliographies publis:\:l.ed by the Bure.au of Mines, Bulletins 149, 165, 180, and 189 being compilations for the years 1915, 1916, 1917, and 1918, respectively. In this bulletin the same general plan has been followed in arranging the references, but a few changes and additions have been made in the classification.

Jan 1, 1923

By Richards S. M

The abundances and abundance relationships of lead, zinc, copper and silver in the major sulphide lenses at Broken Hill are examined, and their possible geochemical significance discussed.When expressed as atoms per cent, zinc is the most abundant base metal throughout the whole .group of orebodies, the highest average lead: zinc ratio (No. 2 lens) being about 0·45, the lowest (No. 1 lensZinc Lode group) being in the 0·12-0 ·14 range. Lead and silver are clearly higher in the lower two orebodies, but the abundance of zinc shows no apparent relationship with stratigraphical position. Among the base metals copper is conspicuously low and remarkably uniform, a feature noted in other conformable orebodies.Although, as has been recognised for many years, abundances of silver and lead, and lead and zinc, are sympathetically related, correlation within the pairs is variable and generally of low degree. Silver and lead show distinctly the better correlation, particularly in No. 3 lens. On the basis of lead: zinc ratios, No. 2' and No. 3· lenses, on the one hand, and the No. 1 lenses, Rhodonitic and Siliceous Zinc Lodes on the other, constitute two groups. However on the basis of silver : lead ratios, No. 3 lens stands alone, No. 2 lens showing clear affinities with the higher layers. Ternary relationships between copper-zinc-Iead and silver-zinc-Iead emphasize the very close constitutional relationship between the No. 1 lenses and the two "zinc lodes".The possible implications of these relationships are then discussed in the light of the' two principal theories-hydrothermal replacement or chemical sedimentation-held for the formation of the Broken Hill ores. It is pointed out that the ratios of the four metals in the ores are rather different from those found in most igneous and sedimentary rocks, and in seawater. For 'example, whereas copper and zinc are present in almost equal amounts in most terrestrial materials, copper in the ores is only about one-hundredth of the amount of zinc. Lead has increased somewhat, but the ratio of silver to lead has fallen; in spite of its recognition as a source of silver, the Broken Hill lode is impoverished in silver with respect to lead as compared with most common terrestrial materials.No solutions are offered to these prob'lems of abundance. Rather it has been the aim of the work to provide data, and to demonstrate the...

Jan 1, 1961

By A R. Heath, I Arbuthnot

Feed slurries are typically flocculated in a thickenerÆs feedwell to increase the settling rate, underflow density and overflow clarity. High molecular weight polymeric flocculants are normally used, but present a number of challenges in terms of make up, dilution, delivery and mixing with the feed slurry.Various aspects of the flocculant dilution and delivery system have been studied with a combination of flow visualisation and computational fluid dynamics (CFD). An open topped flocculant dilution/mixing box has been developed to replace a conventional flocculant manifold, with improvements to the mixing, fault diagnosis and ease of determining the flow split to the various dosing points. The addition points to the feedwell have also been studied, both in terms of where the flocculant is added, and how. While conventional multi-hole spargers are effective in dispersing flocculant, they are prone to blocking and have been replaced by open-ended pipes. The required dispersion is provided by an efficient mixing element placed in the dilution port. Adding the flocculant into the feedwell dilution stream prior to mixing with the slurry also provides super-dilution of the flocculant that can further improve the flocculation process and reduce flocculant consumption.CITATION:Heath, A R and Arbuthnot, I, 2013. Advances in thickener flocculant delivery, in Proceedings MetPlant 2013 , pp 86-92 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

"As mine head grades decline and orebodies become more complex, traditional mineral processing techniques and flowsheets to achieve saleable concentrate become more difficult to design and construct. Mines with lower quality concentrates or concentrates with penalty elements are particular under threat. The economics of these operations are far more susceptible to metal price, concentrate treatment terms and the availability of other, cleaner concentrates. Additional value may be realised for these orebodies through improved recovery by producing a low grade middling concentrate for further processing, in conjunction with a saleable concentrate.The most cost effective way to reduce impurity levels is to do so as early as possible in the mining value chain. Technologies such as fine grinding and fine particle flotation are well established as effective methods for impurity rejection in mineral processing. What is normally overlooked is how a hydrometallurgical process could also be integrated in the overall flowsheet to achieve higher overall recovery at the mill. In the base metals environment, this is mainly because hydrometallurgical processes are associated with production of metal or use of expensive and toxic precipitating agents once the minerals of interest are solubilised. These processes can be very expensive, particularly with rising power costs and poor economies of scale in capital costs associated with low production rates from middling streams.Glencore Technology (GT) has recent experience in the treatment of middling and low grade concentrate streams as well as tailings streams to compliment a concentrator flowsheet in a refractory gold and base metals setting. The value proposition is the isolation of a low grade middlings concentrate from the primary circuit or the tailings stream for upgrading to an intermediate product with an equal or higher grade than the primary concentrate to allow blending for sale. This allows plants to operate on a more favourable part grade-recovery curve while avoiding the expense of metal production. For existing operations this is particularly attractive since it can be added on with no process interruptions.Two case studies are examined showing flowsheets and costings to arrive at the value proposition of the GT low grade treatment flowsheet."

Jan 1, 2017

By C. E. Gregory

In terms of a Research Proposals supported by a Grant Agreement dated 30 June 1973, the author was commissioned to prepare an annotated bibliography of mine fires. The main objective was to conduct a comprehensive program of library research and search of official files to prepare a list of articles dealing with actual occurrences of mine fires. This bibliography as now completed includes an annotated reference from each article or report cited, underlining the cause, extent, methods used, procedural errors made, results achieved, ventilation effects, and lessons learned from the operation of subduing the particular fire.

Jan 1, 1974

By Chester M. F. Peters

INTRODUCTION There has been considerable discussion in recent years of the strained relations between owners, engineers and contractors caused by the rapid increase in costly litigation in underground excavation due to construction claims. These time consuming claims are not to the best interests of the industry. It has been a conclusion of some of the concerned parties that there could be a substantial reduction in these claims if a mutual respect for each other's roles could be maintained along with a practical contractual arrangement for sharing the risks of the unforeseen costs inherent in the business. This paper will touch on the overall problem of these relationships, but confine the major discussion to the role of geology in claims and, in particular, changed conditions claims, since they form the base for the bulk of those involving geology. Geologists can make a major contribution to the reduction of these claims if their particular abilities are recognized and used properly. CLAIMS AND GEOLOGICAL RISKS The tunnel contractor is strictly bound by the contract he signs, and the risks he assumes thereby must be priced. The most important variable factor on which he must base his price is the geologic data provided and his interpretation of it. If this data does not give a clear picture of the conditions, making it impossible to price

Jan 1, 1974

By C. Sykes, E. Turner, M. Wyart-Remy

This paper follows that of the Milos Conf, 2002 and examines the collection and reporting of SDIs in the industrial minerals industry in Europe. It compares the characteristics of the GRI Reporting Guidelines, with its Metals and Mining Sector Supplement with those of the EU DG Enterprise Scheme, launched in 2001. The particular issue of SME's and companies which are not publicly traded is examined. The pros and cons of participating in such schemes is a central theme of the paper. The paper concludes that there and many business benefits for these companies in participating and submitting their data. The European Commission Scheme is strongly recommended for companies in the sector which are SME's and not-publicly traded as well as large firms who are listed on European Stock Exchanges.

Jan 1, 2005

By I. Campbell, P. C. Jones, E. G. Potter, R. P. Taylor

"The Cobalt embayment is a large domain of Paleoproterozoic clastic sedimentary rocks that unconformably overlies the Archean Abitibi greenstone belt. Regionally extensive sills and dikes of Nipissing diabase, emplaced circa 2219 Ma, occur throughout the embayment and are the preferential host to gold-bearing polymetallic vein systems on the Merico-Ethel property, near the northeastern margin of the Cobalt embayment. These gold-bearing, polymetallic veins are predominantly east-west-trending, steeply dipping, discordant calcite- quartz vein systems that formed close to the time of crystallization (within ~15 m.y., based on Pb-Pb ages) of the Nipissing diabase. The ore mineralogy is complex in character, typically comprising sulfides, arsenides, native metals (gold and silver), and specular hematite, preferentially concentrated along the interface between silicate and calcite gangue. A simplified sequence of mineral deposition in the veins is: (1) "Early-stage" pyrite ± chalcopyrite hosted in quartz ± chlorite gangue; (2) "Main-stage" polymetallic (Cu + Co + As + Ag + Au + Bi ± Pb ± Ni ± U) sulfides, arsenides, and native metals hosted in calcite gangue; and (3) "Late-stage" calcite flooding ± galena. Wall-rock alteration in Nipissing diabase is restricted to narrow (<5 cm) haloes of calcite-chloriteepidote- bearing assemblages, whereas a weak alteration halo of specular hematite, calcite, and allanite-epidote has been observed in the surrounding sedimentary rocks. In terms of their age, geology, mineralogy, paragenesis, and morphology, the gold-bearing vein systems at Merico-Ethel closely resemble the silver-sulfarsenide vein deposits of the historic Cobalt and Gowganda mining camps. These observations indicate that the Au-bearing veins are variants of the Ag-vein systems and as such, have a common genesis belt. L’Échancrure de Cobalt est un large domaine de roches sédimentaires clastiques d’âge Paléoprotérozoïque qui reposent en discordance sur la ceinture de roches vertes d’Abitibi d’âge Archéen. La Diabase de Nipissing, mise en place vers 2219 Ma et qui constitue un réseau de sills et de dykes d’importance régionale, est présente dans l’ensemble de l’échancrure et constitue la roche-hôte principale des systèmes de veines aurifères-polymétalliques de la propriété Merico-Ethel, près de la bordure nord-est de l’Échancrure de Cobalt. Ces veines à minéralisation aurifère et polymétallique constituent un système de veines de calcite-quartz sécantes d’orientation principalement est-ouest et à pendage fort qui se sont formées peu de temps après la cristallisation de la Diabase de Nipissing (à ~15 Ma près, d’après les âges Pb-Pb). La minéralogie de la minéralisation est complexe; elle consiste typiquement en sulfures, en arséniures, en métaux natifs (or et argent) et en hématite spéculaire, préférentiellement concentrés à l’interface entre les silicates et la gangue de calcite. La séquence de déposition simplifiée des minéraux dans les veines est : (1) «Stade précoce» pyrite ± chalcopyrite encaissés dans une gangue de quartz ± chlorite; (2) "Stade principal" sulfures polymétalliques (Cu + Co + As + Ag + Au + Bi ± Pb ± Ni ± U), arséniures, et métaux natifs dans une gangue de calcite; et (3) "Stade tardif" calcite massive ± galène. L’altération pénétrative de la Diabase de Nipissing est confinée à des halos étroits (<5 cm) présentant des assemblages marquées par la présence de calcite-chlorite-épidote, tandis qu’un faible halo d’altération en hématite spéculaire, calcite et en allanite-épidote est noté dans les roches sédimentaires environnantes. De par leur âge, leur géologie, leur minéralogie leur paragenèse et leur morphologie, les systèmes de veines aurifères de Merico-Ethel ressemblent beaucoup aux gîtes filoniens d’argent-sulfoarséniures des camps miniers historiques de Cobalt et de Gowganda. Ces observations indiquent que ces veines aurifères constituent une variante des systèmes des veines argentifères et qu’elles partagent"

Jan 1, 2009