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By Daniel C. Boteler

Five lignites from the northern Great Plains province were carbonized at temperatures from 500° to 1,000° C in a bench-scale unit. A replicated Greco-Latin square experimental design was employed to allow testing of four independent variables at five levels. Independent variables investigated were temperature, source of lignite (mine), weight of charge, and moisture content of charge. Dependent variables were char yield, tar yield, light-oil yield, tar plus light-oil yield, carbonization gas yield, and carbonization gas heat yield. An analysis of variance indicated that, at the 99-percent confidence level, the independent variables of carbonization temperature, source of lignite, and weight of charge were significant for yields of char, tar plus light oil, and carbonization gas, whereas moisture content was only significant for carbonization gas yields. At the 95-percent confidence level, moisture content significantly influenced the carbonization gas heat yield per pound of lignite charge and the yields of dry tar plus light oil. All dependent variables were determined on a moisture- and ash-free basis. Multiple regression equations for predicting seven different factors of carbonization yields as functions of carbonization temperature and initial composition were developed using computer techniques. Equations for yields of char, tar plus light oil, and carbonization gas were compared with equations previously developed by others at the 500° C level.

Jan 1, 1970

By K. L. Ludeke, A. D. Day

For many reasons, it appears that deep rooted, perennial shrubs offer potential for improved stabilization and provide maintenance free vegetative cover to harsh sites where perennial grasses have not been successful. The major objective was to select various shrub species of arid plants for initial soil stabilization of disturbed mining areas. The very fact that a drought-adapted shrub has a massive root system that can use moisture from a greater volume of mineral waste soil materials suggests that arid environment disturbed soils may be vegetatively stabilized using desirable forage shrubs. A secondary effort is underway to assemble information and plant materials of promising species from many arid regions of the world for reclamation of mined lands. Surprisingly, many of the better plants for arid sites are quite high in protein content. With proper management, breeding, and selection, they may prove to be very desirable livestock feed when mined lands are used in range land areas. Advancements in arid land solid waste stabilization hold favorable promise for many industries that mine and mill in arid regions for effective reclamation of disturbed areas. Particularly exciting is the possibility of establishment of high density maintenance free vegetative cover of climax vegetation that reclaims the disturbed area back to its original land use. Due to high shrub productivity, stabilization potential, nutritional quality, and reclamation success, greater use should be made of shrubs in disturbed land reclamation associated with mining and milling operations in harsh aril environments.

Jan 1, 1986

By B. Howerton, M. M. Matlock, D. A. Atwood

In the Gold-Cyanide Process (GCP) the cyanide anions act to solubilize the gold and silver present in the ore, and mercury as well. The resulting mercury and cyanide rich effluent are serious health and environmental problems. Currently, there is no mercury treatment from the ore leach solution since there are no precipitating agents or other technologies which can be used effectively in the pH ~ 10solutions. Recently, however, we have developed a new chelate ligand that is impervious to this level of pH and it can be used to precipitate Hg from NaCN solutions. On an actual sample taken from an active gold mine the chelate selectively reduced the mercury level from 34.5 ppm to 0.008 ppm within 15 minutes. Importantly, the gold and silver levels remained unchanged throughout this process. Thus, the environmental impact of Hg released in the GCP can be drastically reduced. Moreover, with a mercury treatment technology now available it may be possible to change, or reinvent, the entire GCP process.

Jan 1, 2003

There is an alternative theory of the high grade orebodies of the Middleback Group, based on the primary nature of the high grade ores in an area of carbonate deposition, with lesser amounts of siliceous and aluminous sediments. The environment is thought to have been unstable, possibly volcanic, and to have been a subsiding basin, substantially isolated from the open sea.Jaspilites, iron bearing talc rocks and iron bearing carbonate rocks were derived from the primary sediments by metasomatic alteration after metamorphism.The metasomatic agents were carbon dioxide and water vapour which were mobilized from the primary dolomite and reacted with a metamorphically produced group of iron bearing and iron free amphiboles, forming talc and progressively releasing silica and iron oxides from the iron amphiboles.The talc rocks in turn released silica which reconstituted jaspilites into their present 200 ft thick crust or zone.The theory accounts for the present disposition of a jaspilite zone over a talc zone which in turn overlies a carbonate zone, and accounts for the down dip changes found in bores which penetrate these zones.INTRODUCTIONIron Duke (Fig. 1) lies some 34 miles south west of WhyalIa in South Australia, and is the most southerly ore body in the Middleback Ranges.The Middleback Ranges are divided into a northern range and a southern range meridionally disposed and separated by an erosion gap called Kimba Gap.The South Middleback Range contains four orebodies;Iron Duke at the southern extremity, Iron Duchess north of Iron Duke and on the same ridge, Iron Knight also on the same ridge, which has been breached by erosion between theDuchess and Knight orebodies, and north east of Iron Knight, the Iron Chieftain.Cook's Range is the eastern range of the South Middleback Range and no large orebodies are known to occur there.

Jan 1, 1963

By John A. Cordes, John J. Schanz

INTRODUCTION The economic structures of industrialized countries require a continuous supply of reasonably priced and appropriately processed nonfuel minerals. As a result, national policy makers are sensitive to real or perceived threats to the effective operation of these commodity markets. Their most persistent concerns can be subsumed into the related political economy issues of supply availability and marketplace stability. These concerns are not new. For over a century the "global struggle" for mineral resources has influenced national policies and international relations (Eckes, 1979). During the past two decades the complexity of these issues, if not their place on national political agendas, has increased. Dramatic changes in the structure of mineral industries and in the nature of international economic relations have redefined policy needs and response options. This paper focuses on how selected OECD countries have responded to nonfuel mineral industry issues over the past twenty-five years. Particular emphasis is placed on the impact these policy decisions have had on the size and location of productive capacity and its utilization rates. The results, perhaps, are not surprising for this group of market- oriented economics. While individual cases of significant impact are easy to identify at various times in most countries, the overall importance of policy decisions has not been great. This is especially true for the past decade when excess capacity reached unusual highs of magnitude and duration. Macroeconomic forces and market structure changes played much more important roles. PERSPECTIVES ON THE ISSUES OECD nations dominate the international nonfuel minerals marketplace as producers, consumers and traders. In 1986, these twenty-four countries accounted for 75 percent of the Western world's export trade value in minerals, ores and metals. They imported 88 percent of the total value. During 1966, the respective percentages were 70 and 94. Japan was the world's largest importer in 1986 followed by the US, FRG, UK and France. The same five countries led the 1966 list except that, then, Japan was ranked fourth. Table 1 ranks the fifteen largest Western exporting nations in the two specified years. It also indicates the growth in current export dollars earned in 1986 compared to 1966.

Jan 1, 1989

This excellent, concise paper by Dr. Iwasaki on the principles of selective flocculation for iron ores discusses many of the principles and problems which have occurred in our bench and pilot plant test-work. The use of sodium tripolyphosphate in combination with sodium silicate as a dispersant is very effective. However, this may cause a problem with the environmental groups as phosphorous is a nutrient. We have also established that the lower the Ca level in the pulp solutions the greater the dispersion. We have found that ores from the same geological strata, having the same general mineralogy and iron content will sometimes have widely different degrees of dispersion. There was-no difference in the gross mineralogy but the solubility of the Ca and SO ions was much less in the ores most easily dispersed. Research efforts should be directed towards a more practical means which would more easily enable one to predict the amount of dispersant required for the various ores. With regard to water quality we have found that waters having higher contents of SO4 and C1 ions hinder dispersion. This could be a method of controlling too much dispersion by the addition of sulfate or chloride ions. This would require further investigation. We have had no trouble with agitation speeds of up to 925 rpm in conditioning starch with the dispersed pulp prior to selective flocculation. We have found about 0.3Lb/LT of starch to be sufficient for selective flocculation on our ores. The increasing of the starch to 1.25Lb/LT has had no effect on the metallurgy of the selective floccula-

Jan 1, 1979

By Armoo K, Tran T

Cementation has been widely used in several hydrometallurgical processes for recovering gold and silver from process liquors. The process is electrochemical in nature, in which gold and silver are precipitated from the solution using less noble metals such as zinc, iron and copper. This paper summarises the current practice of gold cementation from cyanide liquors using zinc powder. Various developmental studies on the cementation of gold and silver from various systems (chloride and bromide) are also reported.

Jan 1, 1991

A study is presented of the theoretically possible initiation systems for outbursts and the subsequent propagation mechanism.Previous occurrences of outbursts and their correlation to the theoretical system are described. An estimation of the energy release from two energy sources, gas strain energy and rock/coal strain energy, is presented and the relative importance of each source in the severity of outbursts. Summary: The description of mechanisms of outbursting follows the examination of these phenomena at Collinsville in Bowen No. 2 mine and at Leichhardt Colliery, Blackwater. Quantitative material contained in the paper refers to Leichhardt Colliery, Blackwater. Clearly from the work carried out to date gas release has a major part to play in the out- bursting at both of these collieries. In the case of the December 1 1978 outburst at Leichhardt Colliery energy release estimates place gas strain energy release contributing eight times the energy of that from rock/coal strain energy. Even the normal outbursts at Leichhardt Colliery appear to show this trend. Estimates of energy released are for comparative purposes between gas and rock strain energy and the values obtained may be regarded as approximate.

Jan 1, 1980

By D. Brisebois, J. M. Fecteau, S. Poirier

"This paper focusses on new developments regarding thermal rock fragmentation applications. The technology consists of a strong burner powered by diesel fuel and air. The thermal reaction that is created allows for the enlargement of 125 mm to 450 mm holes by breaking the rock in a spalling effect. It has been used for over 30 years in Russian open pit mining. Following an agreement between Dynamitage T.C.G. Inc. and the owner of the technology, major improvements have been brought to this technology, allowing for the fabrication of a prototype suitable for the Canadian industry. In Russia and the Ukraine, thermal rock fragmentation is actually used to drill large diameter holes in surface mining. Upon having acquired a better knowledge of this technology, it seems that it presents a great potential for selective mining in narrow-vein operations, for either surface or underground mining.Rocmec International Inc., a subsidiary of Dynamitage T.C.G. Inc., and Natural Resources Canada are technical partners in the evaluation of the operational parameters and environmental aspects such as gas, heat, dust and fog emissions. Furthermore, Canada Economic Development is a financial partner in this project.This paper presents the technology and its history. It also reports on the changes brought to the equipment to adapt it to North American environments. A summary of the tests carried out since 1995 is provided, along with the main conclusions obtained. The anticipated applications for the use of this technology in both surface and underground environments are described such as open pit mining, bulk sampling and narrow-vein ore extraction. An estimate showing a comparison between the thermal fragmentation mining concept and the long-hole mining method is presented and, finally, the future developments planned are listed."

Jan 1, 2003

By George Petersen G.

El siguiente texto describe la genealogía de la pegmatita, composición, precios y las regiones compuesta de este mineral en el litoral peruano. Las pegmatitas son rocas ígneas que se forman al enfriarse la magma, constituyéndose en un etapa de transición y sistema mixto entre los depósitos líquidos magmáticos. Su textura es de grano grueso y está asociada a las rocas ácidas como el granito y la granodiorita. De acuerdo a su genealogía se dividen en dos grupos: facies pegmatítico-magmática y enumatolítica. Las pegmatitas del litoral peruano contiene minerales no metálicos como ortoclasa, mica y cuarzo. Las zonas que comprenden mica son Matarani. Quilca y Atico (Arequipa), la zona de feldespatos se encuentra en Samanco (Chimbote), y la zona de cristal de roca y minerales radioactivos, en la región de Casma (Ancash).

Jul 20, 1961

By P. J. Lechler

A review of the geology and mineralogy of several of the better known hydrothermal platinum-group metal (PGM) deposits is undertaken. Along with new data from two recently discovered occurrences in Nevada, a number of common characteristics of these deposits are identified. Newly described PGM occurrences in Nevada are the abandoned Gibellini mine workings characterized by limestone-hosted hydrothermal Mn-V-Zn-Ni mineralization and the granite-hosted base-and precious-metal veins of the Gingerload claims.

Jan 1, 1989

By Sudhir Kumar Kashyap

In underground activities ground control is a challenging problem. It affects safety, production, and efficiency. As per statistics of accident data, ?fall of roof/sides? is one of the major causes of mine accidents. In many cases, our experiences and understanding of soil and rock behavior still fall short of being able to predict how the ground will behave. Presently, empirical approaches to design are widely used in estimating mine support parameters. Under these circumstances, expert judgment plays an important role, and such accidents can be obviated with accurate measurement and optimization of data and analysis using the neuro-fuzzy technique of artificial intelligence. Recently, a neuro-fuzzy hybrid approach has become one of the major areas of interest in engineering fields because it gets the benefits of neural networks as well as those of fuzzy logic systems, and it removes the individual disadvantages by combining them on the common features. Neural network and fuzzy logic technologies have common features, such as a distributed representation of knowledge, the ability to handle data with uncertainty and imprecision, etc., like in ground control. Fuzzy logic technique has tolerance for imprecision of data, while neural networks have tolerance for noisy data. In this paper we have focused an intelligent technique, i.e., neuro-fuzzy technique, to approximate the setting load given to the standing support (props) erected for the purpose of supporting freshly exposed roof during underground mining. We have used twelve input variables of rock parameters, and after having trained using a neural network with a sigmoidal function as an activation function, simulation was done to find the output parameter, i.e., the pre-load (setting load)to be applied on props. Outputs of the neural network were again fed to the fuzzy system together with the twelve parameters, incorporating five triangular membership functions for each parameter. Final optimum output was approximated using the MATLAB program, which was found to be satisfactory. Neuro-fuzzy technique has better performance over individual neural networks or fuzzy logic technique.

Jan 1, 2012

E. O?C. Acker Jinzoc Adachi Truman H. Aldrich Walter H. Aldridge Anson W. Allen John H. Allen William R. Appleby W. Lawrence Austin W. S. Ayres David Baker John Henry Banks Henry C. Banon Alonzo F. Bardwell Walter A. Barrows H.C. Bellinger Wm de L. Benedict Robert Bentley John F. Berry Andrew A Blair George D. Blood Charles A. Bohn Walter M. Brodie Elwin F. Brown Fredrick Burbidge H.H. Burden Charles Butters

Jan 1, 1944

By L. Yuan, J. H. Rowland III

"In 1995 and 2003, the Mine Safety Health Administration (MSHA) conducted surveys to determine the number of atmospheric monitoring systems (AMS) being used in underground coal mines in the United States. The survey reports showed data for the different AMS manufacturers, the different types of equipment monitored, and the different type of gas sensors and their locations. Since the last survey in 2003, MSHA has changed the regulation requirements for early fire detection along the belt haulage entries. As of December 31, 2009, point-type heat sensors were prohibited for use for an early fire detection system; instead carbon monoxide (CO) sensors are now required. This report will examine the number of AMS currently used in underground mines in the United States to see if there is a change in their use. The locations and parameters monitored by AMS are also discussed. INTRODUCTION The last survey conducted by the Mine Safety and Health Administration (MSHA) on atmospheric monitoring systems (AMS) used in underground coal mines in the United States (US) was in 2003 [1]. The survey report states that since 1995 there had been a steady increase in the use of AMS in underground coal mines as the technology of CO sensors was improved by manufacturers. AMS had become more reliable and some CO sensors could be purchased with the capability to discriminate between the CO produced from a fire versus CO produced from diesel equipment. This increase in reliability had reduced the number of false alarms and the response time. The faster response time to a developing fire allowed for the miners to take the necessary action to put out the fire or exit the mine. It should also be noted that at the time of last MSHA survey, some mines still used point-type heat sensors to detect the presence of a fire on conveyor belts. This detection method works by measuring the temperature of the air around the sensor. As a fire starts to develop, smoke and hot gases are produced from the combustion process, and the air is heated up. Once the air and gases reach a designated temperature detected by the point-type heat sensor, a fire alarm signal is generated. Studies have shown that the response times for detecting the presence of a fire using CO sensors are much shorter than using point-type heat sensors [2]. Finally, since the last MSHA survey, regulations have changed on the type of automatic fire detection systems permitted to be used in conveyor belt entries. As of December 31, 2009, point-type heat sensors are not permitted to be used for fire detection in underground coal mines in the US; instead CO sensors are required as a replacement (30 CFR 75.1103-4). This study will examine how the changing of the above regulations has impacted the use of CO sensors in underground coal mines in the US compared to their use based on the last MSHA survey. Importantly, in the previous MSHA survey, the data was recorded for producing and non-producing coal mines. In this study, only the data from the producing coal mines was recorded. Data was collected from a total of 235 coal mines for this study with the help of the MSHA district offices."

Jan 1, 2017

By L J. Ingle, K L. McPhee, A G. Hunt

Iron Road Limited (IRD) is currently developing the Central Eyre Iron Project (CEIP) at Warramboo on the Eyre Peninsula, South Australia. The project consists of a 30 year open pit mine, magnetite processing facilities, standard-gauge railway and deep water, Cape class capable port. Major South Australian government approvals have been received and funding arrangements confirmed.The 4.5 Bt Mineral Resource (3.7 Bt Ore Reserve), the largest in Australia and among the largest globally, is to be mined to produce 24 Mt/a high-grade, 67 per cent Fe, magnetite concentrate. This in-demand, premium product has a P80 of ~100 µm, suitable for both direct sinter feed and an additive in pelletising.The extensively drilled, homogeneous orebody is unique in both geology and mineralogy; only averaging 15 per cent Fe yet coarse-grained with almost negligible phosphorus and sulfur content. This has allowed significant opportunities to tailor the mining method to the orebody, utilising both optimised blasting as first stage comminution, as well as in-pit crushing and conveying (IPCC) to reduce the heavy haulage diesel fleet and optimise the pit shell.Approximately 1 Mt/d of total material, ore and waste, is required to be moved from the pit daily, introducing materials handling challenges, overcome by a flexible IPCC set-up, multiple overland conveyors and an exacting mine plan. Non-conventional waste and tailings storage is utilised to allow for significant water savings, progressive rehabilitation and minimisation of land impact.The processing facilities utilise both the magnetic and density properties of the magnetite to beneficiate the ore. The coarse-grained nature of the ore is exploited to minimise comminution yet still liberate a high quality product. Utilisation of modular construction methods allows risk reduction during construction and reduced pumping requirements during operation.This paper highlights the uniqueness of the CEIP, with focus on the mineralisation of the orebody, and the beneficial impacts this has on both the proposed mining method and processing. Magnetite mining is not new and IRD has used the learnings of others, and input from various vendors and industry experts, utilising knowledge and expertise to engineer an innovative, yet supported, project design.CITATION:McPhee, K L, Hunt, A G and Ingle, L J, 2017. The Central Eyre Iron Project – developing a new iron ore mine in a challenging climate, in Proceedings Iron Ore 2017, pp 613–620 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By R. N. Roby

In the course of the Bureau of Mines investigations for suitable sources of high-aluminum clay for the production of alumina, the Whiteware clay deposit was examined in August 1942 by G.N. Bennett, mining engineer, Bureau of Mines, Montana District Office. This report presents the factual data obtained by the investigation, which also includes data on trenching and drilling, and the results of some refractory tests and chemical analyses of representative samples of the clay later taken from some of the best trench exposures and from adit dumps.

Jan 1, 1949

By Wilbur A. Haley

One of the purposes of the investigation was to determine and report on how coal augers are used to mine bituminous coal that is near outcrops and may not be mined otherwise by any other present-day method. Such increased overall recovery results in the conservation of coal resources. Other reasons for the investigation were to determine and report the production rates of such operations and the types of equipment used. Auger mining of coal as a means of coal recovery supplementary to strip mining has been introduced and developed since World War II. This type of coal mining has grown rapidly, and bituminous-coal production by auger mining has been estimated at 6,000,000 tons in 1955. Mines were selected for study to give reasonably representative information on auger mining in different types and thicknesses of coal beds in different geographic areas and on different types and sizes of equipment operated under various conditions. This report is based on field studies of 8 auger-miming operations in Pennsylvania, West Virginia, and Ohio and in 5 different coal beds. Operations were observed in active strip mines, in strip mines reopened for auger mining, and along benched coal-bed outcrops. At the time of this study, no augers were reported to be operating in underground mines. The diameters of holes drilled ranged from 26 to 52 inches, and the lengths of holes ranged up to 208 feet. At some operations auger holes often penetrated abandoned underground mine workings.

Jan 1, 1957

Jan 1, 1947

By Z. D. Hora, W. N. Hamilton

Evaporite units of the Western Canadian Sedimentary Basin are known to host native sulfur. In British Columbia, a large number of oil and gas exploration drilling holes reported intersections with native sulfur. The most important ones include 6 meters (20 feet) and 27 meters (90 feet) of native sulfur among 23 occurrences in Devonian Muskeg evaporite or adjacent Slave Point reef facies carbonates. A small Frasch sulfur deposit is known from Devonian Wabamun Group sediments near Camrose in South Central Alberta. Occurrences of native sulfur are common also in association with presently mined gypsum of Devonian Burnais Formation in southeastern British Columbia. Triassic sediments with evaporite members in British Columbia are also known to contain native sulfur showings. A widespread presence of anhydrite in many sedimentary units of Alberta and British Columbia together with oil and gas fields in the same areas and associated native sulfur occurrences point to a possibility for Frasch sulfur deposits in this part of western Canada.

Jan 1, 1992

By S. Nikolic, G. M. Stieper, D. P. Mallah, B. J. Hogg, P. B. Voigt

Copper feed materials processing is becoming more challenging, due to an incremental increase in the mineralogical and compositional complexity of these feeds. These complex and polymetallic feeds are now becoming more common and many sites have been forced to re-evaluate their operating strategies to process these materials at cost competitive rates, whilst meeting ever more stringent environmental regulations. Most operations must first evaluate the merits of pyrometallurgical and hydrometallurgical treatment routes. Although there are multiple copper smelting technologies available, only top-submerged lance (TSL) technology, supplied by Glencore Technology as ISASMELT™, has been applied in the real world to consistently and successfully smelt complex materials in integrated metallurgical facilities such as Glencore’s Kazzinc Ltd. operation in Kazakhstan, Umicore Precious Metals Refining in Belgium and Aurubis AG in Germany. Glencore Technology also offers hydrometallurgical processing, through the Albion Process™ technology, opening up viable flowsheet options previously not possible for these complex feeds. This paper describes a number of real world process flowsheets at global operations and Glencore’s own operations at Mount Isa and Kazzinc Ltd., which process complex feeds. These flowsheets integrate the ISASMELT™, Albion Process™, ISACONVERT™, ISAKIDD™ Tank house, and bottom blown oxygen cupel (BBOC™) technologies to provide an effective process solution for the treatment of complex polymetallic feeds to produce metallic copper and associated by-products. INTRODUCTION Traditional smelters and those built in recent times within the bulk smelting hubs of the world have been designed to treat standard/clean concentrates. In recent years the processing of complex polymetallic sulfide concentrates and the recycling of secondary copper and derivatives of waste electrical and electronic equipment, such as e-scrap, have become a focus for numerous companies (Alvear & Nikolic, 2013). Processing of these complex feeds, characterized by relatively high levels of minor elements (over 5% of elements such as arsenic, antimony, bismuth, lead and zinc) is more challenging. Facilities not designed for these types of materials may require significant modifications or a change in smelting technology to treat them. Often operations find themselves re-evaluating the merits of pyrometallurgical and hydrometallurgical treatment routes for their sites through a number of factors:

Jan 1, 2019