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By J. J. Forbes

This publication is a revision of the first of a series of four Miners' Circulars originally prepared and issued in 19'29 for use in a course of training designed to prepare mine officials to organize men for rescue and recovery operations. These circulars were revised in 1937 and 1938 and again in 1948. This circular (Miners' Circular 33) discusses mine gases and methods for detecting them. The second of this series (Miners' Circular 34) gives instruction in Bureau of Mines methods of sampling and analysis of mine gases; the third (Miners' Circular 35) describes methods and equipment used for protection against mine gases; and the fourth (Miners' Circular 36) explains procedures used in sealing and unsealing mine fires and in recovery operations after mine fires or mine explosions.

Jan 1, 1954

By Robert B. Hopler

The history of the first twenty years of the high explosives industry in the United States begins as an illustration of the free enterprise system at its best and ends with the industry virtually taken over by a single company: a company which strongly opposed the new explosive material at the beginning of the period. In the world of the late Twentieth Century we could almost compare this history to the opposition of the mainframe computer manufacturers to the introduction of the personal computer, and their later entry into, and attempted dominance of, that market. With computers in the twentieth century the attempt to dominate the market has not been particularly successful: with dynamite in the nineteenth century it was.

Jan 1, 1994

Geologists in some underground gold mines collect grab samples from broken ore piles or trucks as a method of grade control. It is often known as muck sampling. Generally, the goal of grab sampling is to try and reconcile the mined grade at the ore source to the predicted grade and/or predict the mill feed grade. The mass of the sample collected is limited by health and safety issues, as well as by the capacity of the laboratory to process the samples within a given time frame. In general terms, grab sampling is known to be problematic because samplers tend to oversample the fines, and/or pick out high-grade fragments; surface sampling of piles does not test material within the pile; muck piles in development drives/faces are likely to be zoned due to the blasting sequence; high or low-grade material may preferentially segregate in the pile during mucking; the five per cent mass reject size of the material in muck piles is very large from underground blasting; some correlation usually exists whereby the larger fragments are enriched or depleted in the critical component of value; and the average error made in estimating the true stockpile grade is likely to be high. The method is prone to chronic fundamental sampling, grouping and segregation, delimitation, and extraction errors. Substantial warnings must be given about the use of grab sampling for grade control in gold mines. The method may appear to work sometimes, which can be attributed to a fine gold particle sizing and more disseminated distribution. As with all sampling methods, its appropriateness must be determined by ore characterization and heterogeneity testing to ensure the method suits the ore type.

Jan 1, 2010

By Q. M. Huang

In 1979 our company undertook the project of infra-structural work of White Swan Lake Hotel, (International class ) Guangzhou. Visit to the site showed that it was situated at the riverside, covering an area of 54,000 M2 with 30,000 M2 of which reclaimed from Pearl River. The material used for reclamation was black sand which was dredged from the nearby riverbed. The sand had the properties of high permeability and very low internal friction. The basement of the building was 6.2 m below ground level and 3 m lower than the riverbed. Apart from the pile foundation, a diaphragm wall was to be constructed prior to the commencement of excavation work for basement. A feasibility study was carried out to determine the method of construction which would maximize utilization of the plants and equipment that were available in the execution of the aforesaid foundation works. This report concerns only the construction of the diaphragm wall and the performance of the plants employed. A detailed delineation of the construction method is herein discussed

Jan 1, 2010

Characterisation and Processing of Electronic Waste for the Recovery of Metal Values Electronic waste (e-waste), which is a hazardous waste, can indeed be a good source of metal values especially for Cu, Pb, Sn including the precious metals such as Au, Ag, etc. In the present work a protocol for sorting and disassembly of e-waste consisting of computers, TV sets and mobile phones, as well as the characterisation and processing are investigated. E-waste consists of assorted materials consisting of metals, plastics and polymers, ceramics and glass. These components are classified into nine categories. The components, in which metal is embedded into non-metallic base, require complete pulverisation for liberation of the metal. The liberation size is observed to be around 1 mm. Several stages of crushing, shearing and shredding and grinding are required to achieve the required feed size. It is evident from detailed chemical analysis that the pulverised particulate is quite rich in metal values. Computer waste has 23 per cent metal by weight with over six per cent Cu while TV waste has 20 per cent metal with about 4.5 per cent Cu. Mobile phones are much richer in metal content with about 56 per cent metal including 32 per cent Cu in it. Metal content is observed to be more significant in the larger size classes and Pb and Cd are found to be the major contaminants. Morphological studies show that a substantial fraction of the particles is flat or elongated. Based on detailed characterisation, a flowsheet is developed involving dry and wet methods to separate the metallic materials from the plastics physically. It is established that according to this flowsheet a metal rich fraction with over 90 per cent recovery of the metal values can be achieved. Considering the relatively inexpensive unit operations involved in the flowsheet it is envisaged that it would provide a commercially viable scheme for processing large tonnage of e-waste.

Sep 13, 2010

The extractive industry has been faced with a situation where there has been no systematic and formalised training and education structure available. Previous structures which were available, e.g. the quarrying diploma and the mining papers as a part of an engineering degree, have suffered the same fate as the Dodo. They are now extinct.   In providing for a training strategy, the past strategies need to be examined and reasons behind their demise examined. This paper examines the reasons for past failures in education and training in the extractives industry, the factors that need to be taken into account in creating an education and training culture, the strategies required, the Government regulations and trans-Tasman agreements, and the quality management which must surround the entire training programme.

Jan 1, 1997

By Eric J. Foell

The Offshore Technology Conference (OTC) was founded in 1969 when a group of scientific and technical societies organized an annual conference and exhibition dedicated to technologies used in the offshore oil, gas and mining industries. Currently, OTC is sponsored by 12 industry organizations and societies. These include: American Association of Petroleum Geologists (AAPG); American Institute of Chemical Engineers (AIChE); American Institute of Mining, Metallurgical, and Petroleum Engineers (AIME); American Society of Civil Engineers (ASCE); ASME International Petroleum Technology Institute; Institute of Electrical and Electronics Engineers/Oceanic Society (IEEE-OES); Marine Technology Society (MTS); Society of Exploration Geophysicists (SEG); Society for Mining, Metallurgy, and Exploration (SME); Society of Naval Architects and Marine Engineers (SNAME); Society of Petroleum Engineers (SPE); and The Minerals, Metals, and Materials Society (TMS). OTC also has two endorsing organizations, the International Association of Drilling Contractors (IADC) and the Petroleum Equipment Suppliers Association (PESA), as well as 6 supporting organizations that include the American Petroleum Institute (API), the Independent Petroleum Association of America (IPAA), the Institute of Marine Engineering, Science, and Technology (IMEST), the International Association of Geophysical Contractors (IAGC), the National Ocean Industries Association (NOIA), and the United Kingdom Offshore Operators Association (UKOOA). From its earliest years, the OTC has been held during the first week of May in Houston, TX, initially at the Albert Thomas Convention Center where OTC?69 drew 4200 attendees and 200 exhibitors. As the conference grew and became established as the world?s foremost event for the development of offshore resources in the fields of drilling, exploration, production, and environmental protection, the venue was changed to the Astrodomain Complex, with technical paper sessions and most exhibits taking place in the Astro Hall. The numbers of attendees and exhibitors varied somewhat over the years, primarily in accordance with the fortunes of the international oil and gas industry. At its height in the early 1980s, OTC registered attendance exceeded 100,000 with more than 2500 exhibitors forcing expansion into the Astro Arena and even the Astrodome.

Jan 1, 2005

By R. L. Beatty

IN INDUSTRIAL and domestic daily life carbon monoxide is the most frequently encountered toxic gas. hazardous concentrations of carbon monoxide may be present in the vicinity of many industrial operations, such as metallurgical processes, coke ovens, and fuel- and synthesis-gas producers, and may be encountered in confined spaces, such as dwellings, garages, workshops, vehicular tunnels, and mining operations, in connection with the use of heaters, boilers, internal-combustion engines, after blasting operations, and after fires and explosions. Evaluation and control of the health and safety hazard caused by carbon monoxide depend primarily on the analytical detection of the presence of carbon monoxide and determination of its concentration in air and in various gaseous mixtures. The choice of method of analysis in any particular situation depends on such factors as required accuracy, range of concentration involved, convenience, speed of analysis required, quantity of sample available, qualitative composition of sample or atmosphere to be analyzed, and possible effects of interfering gases. Some of the methods described require only adequate understanding of operational techniques, whereas others require thorough appreciation and skill in applying the principles involved. The instruments and analytical procedures commonly used for detecting and determining carbon monoxide are described in detail, and reference is made to more specialized methods:

Jan 1, 1955

By A. M. Gaudin, J. H. Brown

In a survey of the effects of heat treatment on the comminution of various rocks, it was found that unusual size distributions often characterize the broken products, and that this is related to a great increase in intergranular fracture1. It is the purpose of the present paper to contribute to an understanding of this effect. In a thesis by one of use, critical consideration was given to many mechanisms which could conceivably be responsible for the increased intergran-ular fracture. It was shown that neither gross chemical changes nor intergranular corrosion are required. Among non-chemical mechanisms the most likely appeared to be (1) Uneven expansion due to thermal gradients, giving spalling (2) In a manner similar to that prevailing in metals, the appearance at high temperature of intergranular weakness. (3) Unequal thermal expansion of adjacent grains. Experiments were designed and conducted to permit a choice among the many alternative mechanisms and in particular among the three listed here. EXPERIMENTAL MATERIALS Tests were made on the materials listed in Table 1. Of each material, only lumps similar in composition and grain size were used. The three marbles listed in Table 1 were analyzed to assure that their chemical compositions did not differ greatly (Table 2). On the basis of the chemical analyses, of differential thermal analyses, and of X-ray powder diffraction patterns, it appeared that the marbles were very similar except for their grain sizes.

Jan 1, 1961

By Cristovão Nery Giacomin

Foi desenvolvido um software para cálculo do balanço térmico dos fornos de reaquecimento de placas da Usiminas em Ipatinga. Ele realiza a busca automática de dados operacionais e das placas reaquecidas, valida, trata os dados e realiza os cálculos das parcelas de entrada e saída dos aportes térmicos para cada forno. Além disso, são calculados o rendimento, a eficiência térmica e o índice de ocupação dos fornos. O desenvolvimento foi realizado em ambientes visuais, com utilização de interfaces gráficas para fácil interação dos usuários com o software. A validação do software foi realizada pela comparação de resultados obtidos na busca automática com valores reais operacionais de balanços térmicos já realizados nos fornos.

Oct 30, 2017

By C. W. Morris

This Final Report describes the major technical activities that were accomplished to produce a comprehensive continuous miner training system (CMTS) for coal industry utilization. The primary product of this program was a continuous miner part-task trainer. It is composed of an interactive computer graphics system combined with the operating controls of a continuous mining machine mounted in a simulated cab. The cab contains an audio system for reproducing continuous miner operational sounds. The trainer is supplemented with a complete set of cognitive materials that provide instruction in the operation, safety and health of continuous miner operations. A complete summary of the field test and evaluation of the CMTS is provided along with a set of recommendations for further training program refinements, expansions, and utilization.

Jan 1, 1982

By Joaquim Luiz Monteiro Barros

Este trabalho tem como objetivo principal apresentar de forma didática e com um exemplo prático a viabilidade da aplicação da tecnologia de recuperação de calor no sinter cooler, com a finalidade de gerar energia térmica (ar quente, vapor, água quente, etc) reduzindo o consumo final de combustíveis na planta.

Aug 17, 2017

By Steve Kral

Conference themes are usually chosen by organizers to reflect the current state of the industry. The Colorado Section MPD came up with what may be the most appropriate theme of a mining conference during the last few years. The local SME MPD section’s theme of its 56th annual conference was “The Wild, Wild World of Mining.” The current boom can be felt in all aspects of the industry, including exploration, mining, processing, sustainability, and economic and political issues. Each of the 25 speakers at the conference, held in Colorado Springs, CO, touched on how the boom has impacted each of those aspects. The meeting attracted about 110 people from around the world.

Jan 1, 2006

By Germán Rodolfo Ocampo Castillo

El presente texto señala la incrementación de la productividad de la mina Xstrata Tintaya -Antapaccay a través del contrato de personal adicional, donde se reemplace a los operadores titulares durante la hora de refrigerio y asi mantener una operación contínua en la mina. Como consecuencia de ello, se incrementará la cantidad del mineral descubierto en la mina y por ende, el costo unitario de las libras de cobre adicional por operación contínua se reduce.

Sep 12, 2011

By Tiziana Apuani

The study refers to an area of about 70 km2, extended in the Italian Central Alps along the the San Giacomo Valley where different civil and mining works are present The regional geological setting is related to the Pennidic Nappe arrangement, characterized by the emplacement of sub-horizontal gneissic bodies resulting from the Mesoalpine isoclinalic folding of crystalline basements, emplaced throw East, and separated by matasedimentary cover units. The investigated geological rocks, belong to the ?Tambò?Unit, overlapped by its meta-sedimentary cover and by the ?Suretta? Unit. The tectonic contact gently dips to the E?NE. The valley, furrowed by the Liro Torrent, follows a N?S striking tectonic lineament, almost parallel to the nappe contact. A number of more then 70 sites, distributed in the studied area, were chosen and detailed structural and geomechanical field surveys were performed to characterize the rock masses, its intact rock and discontinuities. The procedure identifies the number of joint sets, their representative orientation, the set spacing, the type of movement, the amount of dilatation, the degree of alteration, the roughness coefficient, the presence and nature of infill. Rock mass quality indexes, such as the Rock Mass Rating (Bieniawski, 1989) or the Geological Strength Index (Hoek et al. 2002) have been evaluated in each surveyed site. The work is a contribute in assessing how the geometrical and geomechanical properties of the rock masses can be regarded as regionalized variables. The spatial distribution of these properties is a function of the geological and structural phenomena at which the rock masses have been subjected. The presented geostatistical analysis regards the spatial variation of the orientation of the most representative joint set.

May 1, 2009

By S Adamson

Morphological analysis of alluvial gold recovered from the same segment of a placer by four common commercial methods indicates that gold shape and the presence of quartz intergrowths or sulphide overgrowths substantially influence the recovery efficiency of each method. The amount and types of gold saved by each method varies according to the different hydrodynamic conditions under which each of the methods operates. Reverse circulation drilling has the lowest efficiency and preferentially loses moderate-high flatness gold and intergrown or overgrown gold particles with relatively low density. Gravity riffle, hydraulic riffle, and jigcentrifugal concentrator systems respectively save progressively more of these problematic gold morphotypes, but still lose significant and sometimes substantial amounts (of profit) to the tailings. Because of the differences in recovery efficiency, reverse circulation drilling probably underestimates the grade of most placers and may have resulted in bypassing several economic deposits. Losses to tailings by commercial recovery plants arise from inadequacies in fundamental plant design features. These inadequacies compromise plant efficiency by limiting the ability of plants to simulate the wide range of hydrodynamic conditions necessary to operate effectively throughout placer systems. Incorporation of sand pumps and multiple recovery methods into the more sophisticated plants only partly overcomes these inadequacies. At best, efficiency will be maximised in a few segments of the placer determined by individual plant design, and will decrease progressively upstream and downstream of those segments. Without prior knowledge of the morphological characteristics of the gold to be mined, it is difficult to choose the most appropriate plant design, or to estimate what proportion of the gold will be recoverable by any given plant. If the relevant relationships are not considered beforehand, the recovery plant is likely to lose a significant proportion of the gold, and sacrifice maximum profit.

Jan 1, 2001

By P. R. Clifford

Phosphogypsum is a byproduct of the manufacture phosphoric acid. There are approximately one billion tons of phosphogypsum stored in stacks in northern and central Florida. The Florida Institute of Phosphate Research (FIPR) is investigating potential uses of phosphogypsum. These include using phosphogypsum as a road base material, as a soil amendment in agriculture, as a daily cover in landfills, and as a construction material. The results of this research will be presented and will be discussed in light of regulatory barriers to the use of phosphogypsum.

Jan 1, 2002

By M Eggers, H Baxter

This paper discusses the geotechnical condition of bedding shears and small- and large-scale faults and shears in Archean banded iron formation (BIF) bedrock, based on observations of core and televiewer images. Information that can be collected includes the orientation of defects, infill thickness, strength and material type, defect shape and surface roughness.The spacing and continuity of bedding shears may be critical to slope design where performance is structurally controlled with bedding dipping out of a wall. The intensity of development of the bedding shear is a useful indicator of the amount of shearing a bedding surface has been subjected to. This can allow for engineering judgement to be used in adopting peak or residual shear strengths along defect surfaces when developing the design.The spacing and continuity of bedding shears may also contribute to the blockiness and degradation of a rock mass where the structural orientation is otherwise favourable. Additionally the condition, thickness and strength of infill of major fault structures can affect slope design and performance, depending on orientation.Comparison of the condition of structures observed in core with the corresponding in situ televiewer image has been made to assess what characteristics are most accurately captured by each technique and whether the additional information gathered from using the televiewer technique is justified by the cost. The question of whether the data collected by a televiewer is sufficient to ultimately replace the need for core is considered.CITATION:Baxter, H and Eggers, M, 2013. Fault and shear characterisation in archean banded iron formation bedrock - a comparison between core and televiewer data collection techniques, in Proceedings Iron Ore 2013 , pp 47-56 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By William G. Pariseau, Mark K. Larson, Heather E. Lawson

Rational design based on engineering fundamentals is essential for the layout of safe, stable shafts and tunnels. Shafts and tunnels including winzes, raises, adits, and crosscuts are lifelines to the underground and must be secure. The contribution of this paper describes a significant extension in existing software previously developed for five important design problems in strata-bound mines such as coal, trona, salt, potash, and some large, lead-zinc mines. This extension in software allows analysis to proceed in three easy steps: (1) preparation of a strata properties file, (2) generation of the finite element model, a mesh, and (3) finite element program execution. Circular, elliptical, and rectangular shaft sections are available for a single shaft, twin shafts, and shafts in a row. Spacing of twin shafts and shafts in a row is a free parameter (pillar width). Tunnel shapes are the same as shafts but include the conventional arched back section. Dipping strata of variable thickness, depth and orientation relative to the excavation of choice are allowed. The analyses are three-dimensional. An elastic-plastic material model based on associated rules of flow and an N-type yield condition for isotropic, transversely isotropic, or orthotropic rock are used for all strata. Example analyses from several hardrock mines are provided to illustrate the three-step process including mesh plotting and plotting of selected results. The goal of this software is to advance mine design technology for improved miner health and safety.

By Carl-John Grävare

This paper deals with some of the systems and equipment that are being developed and/or are in use in Scandinavia. The main subject is the development of loading tests on the piles using monitoring equipment. This paper also describes ground improvement using lime-cement columns, expander body piles and steel core piles.

Jan 1, 2000