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By T. A. Rundle, K. Kim, W. M. McCabe, E. C. Gregory

Overcoring tests were conducted at the Near-Surface Test Facility(NSTF) to assess the suitability of five techniques (U.S. Bureau of Mines borehole deformation gauge (BDG), Commonwealth Scientific and Industrial Research Organization (CSIRO) hollow inclusion stress cell, Luleå triaxial gauge (LuH gauge), and Council for Scientific and Industrial Research (CSIR) doorstopper) for in situ stress determination in a closely jointed basalt. This effort is in support of the Basalt Waste Isolation Project, which is studying the feasibility of locating a nuclear waste repository in the basalts of the Hanford Site in southeastern Washington. This paper presents the results from the overcoring study that formed the basis for selection of two techniques to be used during the further exploration of the basalt formations at depth.

Jan 1, 1983

Definir el concepto de exploración minera conlleva un estudio mucho más allá de las actividades minero-geológicas delimitadas por el cálculo de tonelaje del yacimiento. En este sentido, el objetivo del texto, señala una nueva noción, donde la exploración es un juego de azar caro en el que la extensión del yacimiento se mueve no solo en términos cuantitativos, sino que se invierte grandes capitales con un factor de riesgo. A pesar de esto, se continúa con la ejecución del proyecto, al tiempo que se evalua el apoyo del Estado, pequeños mineros, la Sociedad de Ingenieros del Perú, Instituto de Ingenieros del Perú, entre otros organismos interesados en lograr una economía promisora para la industria minera. Otro aspecto importante en su ejecución, son los factores económicos y costos de producción tales como el aumento de jornales y salarios, costo de materiales y métodos más complejos de exploración. En esta perspectiva, la exploración se convierte en una forma de investigación que no requiere una logística compleja para el nuevo producto, aunque el enigma de la certeza persiste. Así, se necesita buen criterio y experiencia para determinar la etapa de exploración en la que los trabajos adicionales no son justificados ni necesarios. Una vez determinada el área a explorar, se necesita la adquisición de los derechos mineros, para la exploración primaria y asi aplicar el levantamiento geológico de la zona, que fijará una tasación aproximada dentro del espacio explorado. Por último, el estudio revisa la eficacia de exploración de las minas de Cerro de Pasco, como en Oyón, Cuajone, Tintaya, Yarabamba y Antamina, concluyendo que es necesario el empleo de las nuevas técnicas de exploración minera que se practican en otros países a base de una mayor liberalidad del Servicio Aereofotográfico Nacional, asi como es urgente promover un inventario minero-histórico en los 1244 distritos que comprende el territorio peruano en sus 1'331,410 Kil6metros cuadrados.

Jul 20, 1959

By Rick Hyndman

? Context: Ø Global action on climate change ? The situation of trade-exposed industry sectors ? The federal government?s draft plan for industry ? CAPP?s position ? Canadian emissions & Canada?s Kyoto target Simple Economic Theory of Dealing with Externalities ? Put cost on emissions Ø Carbon tax Ø Emission trading with auctioned permits ? GHG costs get reflected in the prices of energy alternatives, goods & services Ø Decisions driven by changes in relative prices ? Switching to lower emission fuels ? More energy efficient ways of producing ? More energy efficient appliances, cars, housing ? Reduced demand for energy intensive goods & services ? Anticipation of higher CO2 price drives low CO2 technology Development

Nov 1, 2002

By Walter Knox, J. D. Doherty

IN 1939, at the request of The Koppers Coal Co., the Koppers Company Research Department established a Stoker Coal Research Laboratory for the purpose of investigating the performance characteristics of stoker coals in typical domestic stoker installations. Fig. I is a photograph of part of the laboratory. The material in this paper deals with the performance of one coal in a single installation. Presented are details of this installation, mechanical characteristics of the stoker, and the results of a series of burning tests in which adjustments were systematically varied. SUMMARY OF RESULTS Mechanical Features I. A large percentage of the total power consumed by a domestic stoker is used to operate the gear case and motor (Fig. 3). 2. The power consumption per ton goes down with an increase in rate of coal feed (Fig. 4). 3. The automatic air control in this stoker showed advantages over manual control (Fig. 5). 4. The air velocities through the retort tuyeres were uniform around the retort, but varied between the rows of tuyere rings (Fig. 6). 5. The crushing of coal with this stoker increased the minus 1/8-in. from 1 1.6 per cent to 19.2 per cent. There was a noticeable segregation of coal as it came from the retort and distribution was not uniform (Fig. 7). 6. Measurement of air entering over the fire showed that with some not uncommon adjustments this air may he a high percentage of the total air supply (Fig. 8 and Table I). Operating Performance I. The removal of clinker was shown to give a period of poor performance characterized by a high fuel-bed resistance and a high percentage of carbon monoxide in the flue gases (Fig. 10). 2. The fuel-bed resistance was found to decrease as the fuel bed built up in a normal response to heat demand after a prolonged hold-fire (Fig. II). 3. With intermittent operation the burning rate was almost always less than the feeding rate. The wide variations were found to be greatly dependent upon the length of the On period and the length of the intervals between On periods (Fig. 12). 4. The maintenance of a low furnace draft led to less fly ash, better clinker formation, and higher efficiencies (Fig. I3). 5. The maintenance of a minimum of excess air also resulted in less fly ash, better clinker formation, and higher efficiencies (Fig. 14). GUIDING PRINCIPLES In planning the investigations, the following principles were adopted: Selection of Healing Equipment.-Use only standard models of stokers and furnaces representative of those widely used.

Jan 1, 1942

By W. F. McDermott

The transportation of solids by pipeline is not new. In 1891 a United States patent broadly covering a method of pumping coal with water was granted to W. C. Andrews. His pilot plant was constructed on what is now the site of the New York Public Library in Manhattan. His process was applied to pumping coal mine waste back into the worked out portion of coal mines. On October 26, 1967, the world's first long distance iron ore slurry line was put into service by Savage River Mines. The commissioning of this 5.0 million dollar installation climaxed three years of development, testing, and construction and proved the Company's faith in pioneering this unique transportation method for iron ore. This paper will discuss some of the more pertinent items in connection with that three- year period. Also to be discussed will be the operation of this line during the past eleven months.

Jan 1, 1968

By L. C. IlsLey

The United States Bureau of Mines has been conducting investigations of electrical equipment curing a period of more than 25 years in an endeavor to encourage the development of safer electrical equipment for coal mines. In order to conduct these investigations in an orderly manner they are carried out under a published schedule of tests known as Schedule 20, which specifies detailed requirements for motors, controllers, etc., and fees covering the various inspections and tests made as part of a routine investigation.

Jan 1, 1937

By William M. Schafer

Forage plots were established on agricultural lands contaminated by acid mining waste. The acid produced through oxidation of pyrite and other sulfides caused elevated solubility and plant availability of copper, zinc, and arsenic which killed vegetation and polluted surface and groundwater. Soil amendments including agricultural lime (CaCO3), hydrated lime (Ca(OH)2), phosphorus, and organic matter were used to reduce the toxicity of metals. Several acid-tolerant grasses were used to vegetate the amended soils. Various soil extraction techniques were used to see which best correlated with vegetation performance. The extractions corresponded to three "forms" of metals in soil including soluble (water-saturation extract); plant-available/weakly adsorbed (DTPA extract); and total (HNO3/H202 extract). Of the extractants tested the DTPA levels appeared to correlate best with metal levels in plant tissue. The DTPA soil extractant serves as a useful tool in predicting potential phytotoxicity of mine waste materials.

Jan 1, 1989

By H. Rosenthal, A. L. Jamieson

THE action of mercury on stressed brass to produce cracks was known before Moore, Beckinsale and Mallinson1 showed that actual season cracking did not occur spontaneously but could be induced by ammonia. These investigators studied other substances, including diphenylamine, without finding that anything other than ammonia could cause season cracking. Grimston2 reported season cracking in cartridge cases stored in wooden boxes wetted with dilute sulphuric acid pickling solution. Season cracking associated with sulphur dioxide, water vapor and air has been reported by Johnston,3 although he reported that trimethylamine and pyridine did not cause cracking. Jevons4 has ascribed season cracking of brass in certain instances to trimethylamine, "aldehyde amine," "ketone amine" and pyridine, but no experimental work was done evidently to prove this definitely. Pyridine was investigated by Morris,' who found it to have considerable cracking power. In the present investigation, the object was a qualitative evaluation of a number of representative amines with respect to their ability to cause season cracking. Thus it was desired only that an appreciable vapor pressure of each amine be obtained in order to make the test as severe as possible, without attempting to test equivalent concentrations for comparative purposes. METHODS Specimens Two types of specimen were used: I. Unannealed 70-30 brass cups formed from 0.040-in. thick sheet. Height of cup was 1 3/8 in. and diameter was 1 7/8 inches. 2. First draw pieces of caliber .50 cartridge cases in the unannealed condition (70-30 brass). The cups were representative of a thin wall and thin base specimen, whereas the draw pieces have a thick base (1/4 in.) and a thick wall (approximately 3/32 in.). Both types of specimens contained high residual stress and cracked in less than one minute in a solution of I per cent mercurous nitrate and I per cent nitric acid provided that this was preceded by a 30-sec. pickle in 40 per cent nitric acid. Specimens were prepared as follows: (I) degreased in trichlorethylene, (2) rinsed in H20, (3) pickled 5 min. in 10 per cent by volume H2SO4 (1.84 sp. gr.), (4) rinsed in H2O, and (5) dried. Amines Tested In selecting the amines, representatives of the three series of amines and one series of substituted amines were chosen. The aliphatic series was represented by the methyl and ethyl primary, secondary and tertiary amines. These are the simplest aliphatic amines. For the aromatic series, the phenyl primary, secondary and tertiary amines were selected as being the simplest. The heterocyclic series was represented by pyridine, which is a simple heterocyclic base (tertiary amine).

Jan 1, 1944

The condition of the domestic mining industry is obviously affected by the cycles in general business conditions. This study, the results of which are presented in a series of 78 charts, attempts to examine the interrelationships between the general business indicators and the major statistical measures for the base-metals industries during the cycles in the United States economy following World War II. For these industries the cyclical problem is perhaps less acute than the secular-trend problem. However, short-run fluctuations in production and employment do have very important impacts upon the welfare of the regions which derive a significant portion of their income from base-metals mining and processing industries. Any information concerning the normal patterns of development as the industries enter into a cyclical recession will permit better forecasts and perhaps help promote measures to alleviate the distress that occurs. Also, a systematic study of the comparative movements among the statistical measures during a series of cycles can bring to the fore the economic causation involved, and perhaps, after intensive study, can lead to a better method of short-range forecasting for these industries. This study has not fully achieved these aims. However, observations which significantly aid the interpretation of the current monthly statistics on these commodities are made, and some very general conclusions are drawn. The charts are presented so the interested people can examine them and draw additional conclusions. The charts refer specifically to cyclical analysis. The technique of indexing each cycle to its turning point effectively subordinates the longer term trend movements of the data. Thus, certain general conclusions flowing from this study and from the continuing economic research of the Office of Chief Economist will aid the reader by clarifying the frame of reference within which the charts should be examined.

Jan 1, 1961

By M. K. McMullen

Mineral Development Agreements (MDA?s) are a cooperative mechanism in Canada by which the federal and individual provincial governments can coordinate their scientific, techno- logical and market development resources in order to implement measures designed to stimulate mineral exploration and development by the private sector; the objective, ultimately, being to increase the mineral industry?s contribution to provincial economies. In the latest round of MDA?s, which was initiated in 1984, a significant number of planned activities relate to industrial minerals. This paper will describe the nature and importance of MDA's in Canada and will outline the wide range of activities taking place with respect to industrial minerals.

Jan 1, 1987

Jan 1, 1994

By Wagner Viana Bielefeldt, Felipe Buboltz Ferreira, Antônio Cezar Faria Vilela

The continuous casting machine is one of the most important steel production steps in a melt shop. The tundish, a reservoir between the steelmaking ladle and the mold, has great influence over the steel cleanliness, along with the productivity bid. It must takes into account the quality of the metal and operational safety. Several different variables are related to the tundish process, of inclusionary cleanliness. Some of them are discussed in this paper: the free opening of ladle, tundish inertization, steel temperature in the reservoir and clogging formation, besides a brief topic about castability. Therefore, a critical analysis, with a review from some papers available in literature, is proposed in this study, with its focus on tundish.

Oct 1, 2019

By Levi Guzmán Rivera

El presente trabajo describe la aplicación de la tecnología de floculación hidrofóbica en la recuperación de minerales valiosos contenidas en lamas y menas con minerales finamente diseminados. Inicialmente, se describe el proceso de flotación de minerales, el proceso de floculación hidrofóbica y las bases de esta tecnología de concentración de minerales. Posteriormente, se presenta un ejemplo de su aplicación en el beneficio de minerales -tanto a nivel laboratorio como industrial. Finalmente, se analizan los parámetros principales que afectan la floculación hidrofóbica. En consecuencia, los resultados obtenidos demuestran que la floculación hidrofóbica es un método viable para la recuperación de valores que se encuentran a un tamaño muy fino.

Sep 9, 2007

By Michael J. Messel

OF the various minerals that occur in fibrous form known as asbestos, chrysotile is the variety most in demand for commercial uses, and, last year, over 683,000 tons of the various grades were produced in Canada and United States, exclusive of African and Russian production, which figures are uncertain. Production has not been able to keep up with the increased demand, and an acute shortage exists. Canada, Russia, and Africa are still the most important producers. However, Russia consumes most of its production at home and exports very little. The United States consumes over 60 pct of the total production and produces only about 4 pct of the total from deposits in Vermont and small quantities from Arizona. This paper will review mainly, some of the more recent developments concerned with the extraction and processing of this fibrous mineral for various industrial uses, such as textiles, insulation, building materials and brake linings.

Jan 1, 1949

By Larry M. Southwick

Steel mill electric arc furnace dust is a RCRA listed hazardous waste and its treatment and/or disposal are regulated by a complex set of rules. These regulations were originally established to encourage recovery and recycling of valuable components. For EAF dust, the more valuable constituents include zinc, lead, cadmium and iron. In fact, current trends are in the opposite direction, as the regulations have complicated the ability to commercialize new treatment technologies and created substantial roadblocks and liabilities for processors. As a result, almost half of the EAF dust generated in 1997 will be landfilled. The problems are compounded by difficult processing requirements, less than sterling examples of technology development and mechanical and operating problems. This paper explores some options to simplify the processing requirements and thereby easing difficulties in commercializing new technologies and expediting the recycling of recovered metals. Dust processing usually includes a simple step followed by two complicated steps. The simple step is fuming of heavy metals away from iron and other residues. The complex steps are (1) separating and purifying the heavy metals and (2) upgrading the iron residue. The first complex step can be simplified by producing an intermediate product that is amenable to processing by zinc refiners. This route benefits from the currently underutilized (by dust processors) resource offered by refiners, who have experience in and existing processes for separation and purification of zinc-based heavy metals. Various processes and their associated product options are reviewed and compared. Future directions for dust processing developments are suggested.

Jan 1, 1998

By J. M. Wempen

As development in underground coal mines progresses away from the critical components of the ventilation system, including the main fans and ventilation shafts, resistance within the system is markedly increased. This results in higher pressure and flow requirements from the main fan(s) to maintain adequate face ventilation. Upgrades to the primary ventilation system are often required. The use of booster fans underground is a potentially practical alternative to the addition of shafts and surface fans. This study presents simulations of the use of booster fans in two underground ventilation scenarios, one longwall and one room-and-pillar. The booster fan effects on the power requirements of the ventilation systems are evaluated.

Jan 1, 2011

By John F. Elliott

Six major trends that have had and are continuing to have major effects on the use and supplies of pig iron and scrap in the United States are (a) gradual replacement of the basic open hearth furnace (OH) by the basic oxygen furnace(BOF); (b) use of the electric furnaces for the production of plain-carbon steels, a trend which is closely related to the first; (c) United States changing from being a net exporter to a net importer of steel; (d) replacement of ingot casting by strand casting; (e) increased exportation of scrap; and (f) the lack of growth of the capacity of the U. S. steel industry to produce pig iron in the last 5 to 8 years. This report gives an analysis of the relationships between these trends and the use of processes for the production of raw steel in solidified form.

Jan 1, 1975

The JORC Code contains a mandatory classification system for Mineral Resource and Ore Reserve estimates for public reporting. The classification is a statement of the Competent PersonÆs confidence in the estimate and an attempt to convey that confidence to the various users of the resource estimate. In general the classification process is either largely subjective, relying on the Competent PersonÆs experience, or relies on statistical measures derived from the estimation process, or is derived from an estimated level of confidence in the outcome. However, the statistical measures may not necessarily relate to the overall confidence in the resource or reserve which must take account of the confidence in the geological inputs to the estimation.In addition to the traditional deterministic interpretation and estimations adopted by geologists, semi-quantitative techniques are now available to improve the estimation of confidence while continuing to involve the Competent PersonÆs experience in the process. Methods for quantifying confidence in mineral resource estimates for advanced projects and operating mines have also been developed.Classification is undertaken primarily as a communication tool between the estimators and the other stakeholders in the process. A brief examination of the stakeholdersÆ requirements is included.

Sep 26, 2011

By Dharmendr Kumar, Pradip, Sivakumar Subramanian, Beena Rai, Venugopal Tammishetti

The separation efficiency in a mineral processing plant is generally assessed and reported in terms of elemental assays constituting the minerals of interest. However, different minerals comprising of same elements behave differently under similar process conditions. Thus, it is imperative to track the mineral composition thank elemental composition of different streams in a processing plant. The availability of automated mineral analyzers such as QEMSCAN and TESCAN in recent times has made it possible. However, due to the high cost and expertise required, their adaptation in day to day monitoring of operations is not yet a common place. X-ray diffraction (XRD) profile fitting (Rietveld Refinement) is another technique which can provide estimates of mineral proportions in a sample. The results of Rietveld Refinement however are affected by coating of fines on coarse particles, method of sample preparation, particle size distribution of sample, elemental substitution in mineral crystal lattice. In the present work, we propose a simple and efficient method for quantitative estimation of minerals in iron ores using elemental assays and thermo-gravimetry analysis data. The minerals (hematite, goethite, gibbsite, kaolin and quartz) are identified using powder XRD analysis. It is also observed that goethite contains Al substitution in the crystal lattice. The samples were analyzed for %Fe, %Al2O3 and %Silica using chemical analysis. The measured Loss on Ignition (LOI) in the sample is contributed from goethite, gibbsite and kaolinite phases. LOI from gibbsite and goethite occur in temperature range 250–350°C and LOI from kaolinite occur in temperature range 400–700°C. According, LOI are determined in two different temperature ranges that are 100–400°C and 400–850°C. We have used the data to successfully determine the mineral compositions of iron ore samples. We have also employed a data reconciliation algorithm on the calculated data for further improvement and consistency of our results. Our method is very convenient for quick estimation of mineral proportions in a sample. The proposed method can also be used for quantitative phase estimation in bauxite ores and red muds.

Jan 1, 2016

By P Moswate, D Phillpotts, S M. Mantsho, P Strobos

A challenge on many industrial flotation circuits is controlling concentrate mineral grades using measurements that are provided infrequently. The mineral grades in concentrate streams are a critical performance indicator in any industrial flotation circuit. Failure to achieve concentrate mineral grade targets has significant financial consequences on a flotation operation. A violation of gangue mineral grade limits by the concentrator may also result in significant penalties.Online grade analysers which can provide reliable real time grade measurements are essential for effective grade optimisation. The Blue Cube MQi analyser (by Blue Cube Systems) has recently come to prominence for its ability to rapidly determine mineral concentrate grades online and has the benefit of operating in-stream. This has provided excellent insight into the actual process dynamics in the flotation circuit, and hence enabled real-time control and optimisation of concentrate mineral grades.MintekÆs Measurement and Control division, specialising in advanced control solutions for mineral and metallurgical industries, has had the opportunity to link the FloatStar Grade-Recovery Optimiser to the measurements provided by the Blue Cube system at the BCL nickel concentrator plant in Botswana. The project focused on stabilising the final concentrate grade while ensuring the final tailings are minimised, resulting in an improved nickel recovery. This site already had the FloatStar Grade-Recovery Optimiser for several years, but the original grade measurement device was unreliable and ultimately failed. The system was reactivated once the Blue Cube system was installed, replacing the old analyser. The positive results show the advantages of combining reliable real time measurements with an advanced process control system.CITATION:Mantsho, S M, Moswate, P, Strobos, P and Phillpotts, D, 2013. The implementation of floatstar grade-recovery optimisation control solutions using Blue Cube Online grade analysers on industrial flotation circuits, in Proceedings MetPlant 2013 , pp 575-582 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013