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By M C. Goode

The use of electrical or electronic safety systems to protect personnel, and the engineering tasks associated with the design, manufacture and maintenance of these systems are referred to using the term ‘functional safety’. In the past ten years, the use of such systems has transitioned from its traditional base, in oil and gas major hazard facilities, to being a part of most large mining and materials handling projects. In particular, functional safety is rapidly becoming a significant component of Australian iron ore projects, typically in the form of emergency stops, remote isolation, drive through interlock, robot cell entry or mobile machine anti-collision systems. While these types of systems have been in use in iron ore for a long time, functional safety standards (eg AS61508, AS62061, AS4024.1503) require more rigourous demonstration of the level of risk reduction provided by the systems.The early engineering project development phases require a number of key decisions to be made around functional safety implementation. The decisions made at this point in a project will go on to dictate the required types of risk assessment and analysis, equipment selection, sizing of substations, and training and maintenance requirements for owners. For project teams that are unfamiliar with functional safety, or inexperienced in its application, an incorrect decision or failure to understand the requirements of the chosen standard can lead to a failure to meet contract requirements, as well as major cost and schedule overruns.This paper examines the implications of functional safety on early engineering studies, focusing on the following questions: How does a designer or company determine what standard is best suited to their project? What key aspects of functional safety design need to be considered during project development? And finally, how can the impact of functional safety to the project be minimised?CITATION:Goode, M C, 2017. Functional safety impacts on study stages of major projects, in Proceedings Iron Ore 2017, pp 347–352 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By B. S. Kim, Y. D. Kim, T. S. Kim, T. B. Kim, H. J. Chae

"The Nd-Fe-B scrap was placed in Fe crucible with pure Mg in an Ar atmosphere, and the scraps were melted using an induction heating method. The effects of experimental parameters such as melting temperature (range of 993K to 1073K) and holding time (15min-600min) on the ability of extraction were investigated. The microstructure and diffusion layers were analyzed by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS), and the constituent phases were characterized using XRay Diffraction (XRD). Diffusion of Nd through the Nd-Fe-B scrap into liquid Mg was described, and the diffusion coefficient of Nd in liquid Mg was estimated.INTRODUCTIONNd-Fe-B magnets are usually produced either from comminuted melt-spun ribbons as bonded magnets or hot pressed bulk magnets, or by sintering in conjunction with prior green compaction in an applied magnetic field (Sagawa et al., 1984). These magnets have been widely used for various electromechanical and electronic devices such as voice coil motors (VCMs) and magnetic resonance imaging (MRI) (Samardzija et al., 2012; Matsuura et al., 2006). The production of the Nd-Fe-B magnets is increasing by about 20% per year because of their excellent magnetic properties. However, the expansion of Nd-Fe-B magnet market induced a concern for the scarcity of Nd at the aspect of natural resource. Therefore, the development of an effective recycling process for Nd-Fe-B magnet scraps is an extremely important issue from the viewpoint of resource and energy conservation. Several recycling processes for the Nd-Fe-B magnets have been proposed (Uda et al., 2002; Lyman et al., 1993]. It has been reported that the best separation of rare-earths from the Nd-Fe-B magnets is obtained by sulfuric acid dissolution followed by precipitation of recyclable rare-earth salts. However, this process can make a large amount of waste water including dangerous solutions. Recently, (Xu et al., 2000) have reported a technique to extract Nd from 18Nd-72.4Fe-0.9B-1.82Pr-5.3Dy (wt.%) magnet scrap by using liquid metal extraction (LME) processing. However, these techniques seemed to be difficult for application, because the scraps consist of an infinitesimal amount of other minor elements (Pr, Dy, Cu, Al and Tb), and these minor elements can make a new intermetallic compounds with Mg. Also, some oxides or the plated Ni metal can be preventable to reaction between solid-liquid (S/L) interfaces. For these reasons, the substantive reaction mechanism between Mg and Nd-Fe-B scrap is not clear. In this study, the simple composition of 33Nd-66Fe-1B (wt.%) magnet scraps were prepared using an induction melting process. The effects of the experimental parameter on the diffusion properties between Mg and scraps were investigated to determine whether these methods could be used in industrial application in a liquid metal extraction (LME) process."

Jan 1, 2012

By Yunnen Chen

The test and use of natural materials as biosorbents for the removal of heavy metals from industrial wastewater is under constant development. In the present study, the biosorption capacity of waste microzyme was studied for cadmium The cadmium removal study has been carried out batchwise where the influence of physico-chemical key parameters such as pH value of solution, contacting time and initial cadmium ions concentration have been considered. The influence of metal ion concentration was evaluated and the results were fitted using adsorption isotherm models. The kinetic of cadmium biosorption was also investigated. The maximum percent removal was attained at the pH 7.0 after about 30 min. Waste microzyme was a potential biosorbent for the removal of Cd(II) from the effluent of electroplating industry.

Jan 1, 2009

By O. C. Blade

"An important function of the Bureau of Mines is promoting the conservation and more efficient utilization of a natural resource. Petroleum is such a resource, and its utilization depends to a considerable degree upon its characteristics. For this reason the Bureau of Mines, over a period of years, has analyzed many samples of crude petroleum by the Bureau of Mines Hempel method 3/ and published complications of crude-oil analyses. Among such publi¬cations are several reports presenting analyses of crude oils from fields in Oklahoma. The most recent of these relates to samples from southern Oklahoma. 4/ The present paper provides additional analyses of Oklahoma crude oils, largely from areas and formations not heretofore represented in published reports. The analyses of 248 samples from 153 fields are presented individually and collectively in the tables of this report.Crude oil has been produced in Oklahoma in commercial quantities since 1891, and peak production was reached in 1947. The State's cumulative production to January 1, 1944, is, according to the American institute of Mining and Metallurgical Engineers, 5,186,466,000 barrels. 5/ The annual production of crude petroleum in Oklahoma for each year from 1891 to 1943, inclusive, is given in table 1."

May 1, 1945

By C. Daniel Kealy

Finite-element,, mathematical models that solve LaPlace's and Richard's equations numerically were used to locate the phreatic surface within tailings pond embankments and to define the subsurface flow of water from the pond. Both must be known to design structurally and environmentally safe tailings dams. The permeability distribution within and beneath the embankment, the fluid potential values upgradient and downgradient from the embankment, and the geometry and elevation of an approximately impermeable layer at some depth beneath the embankment were used as computer inputs in analyzing over a dozen finite-element models of tailings dams varying structurally from simple to complex. Results predicted with the finite-element model were confirmed with measurements in a laboratory model of a tailings pond and in the field. Of particular importance to the design of safe slopes, all data indicated that the phreatic surface within a tailings dam is concave upward, a configuration opposite that in most earth dams. The close correlation between predicted and experimental values confirmed the practicability of using the finite-element technique to design safe tailings dams.

Jan 1, 1971

By Wilson Blake

This report presents the results of a 7-year Bureau of Mines program to review, revise, and make an effective engineering tool of the microseismic method of determining the stability of rock structures. The program consisted of developing new microseismic equipment and data analysis techniques and extensive field investigations to demonstrate the effectiveness and potential of the broad-band microseismic method. The guidelines for choosing the components of a microseismic system are presented along with approximate cost figures. Different microseismic systems are discussed, including completely automated systems. Procedures for conducting microseismic investigations and analyzing microseismic data are discussed in detail. Field situations which show the full value of the microseismic technique as an engineering tool are described.

Jan 1, 1974

By Evangelos Petrakis, Kostas Komnitsas

This study investigates the evolution of dimensional properties of grinding products, namely, the mass, the surface area, the length, and the number of particle distributions with the energy input in a ball mill. The size analysis of the mill products enables the calculation of the mass distribution of each material at predetermined size classes and then the determination of the other dimensional properties by taking into consideration the geometry of the particles. Based on the distribution of dimensional properties, an effort was made to determine whether the grinding products are fractal in nature. The effect of material type and grinding conditions on the relationship between the dimensional properties and the specific energy input was also investigated. Special importance was assigned to the study of the specific surface area and the surface area production rate, both during the initial grinding stages and at higher energy levels. The determination of the surface area production rate allows the identification of the grinding limit and the maximum specific surface area which could theoretically be achieved. This approach has as ultimate objective the maximization of energy efficiency and subsequently the minimization of the high grinding cost.

By F. K. McKean

Introduction The present paper may be considered as a sequel to a paper, A Process for Cleaning Molybdenite .Concentrate, which was presented by the author at the annual meeting of the Institute last year. In that paper, a description was given of the laboratory work leading up to the adoption of a new process for treating complex molybdenite ores of the Molybdenite Corporation of Canada. A bare outline of mill performance with the new flow-sheet was included. With this writing, the purpose is to describe the highly interesting work of translating laboratory experience into mill practice, to show what changes were required in design to put the scheme on an operational basis, and to point out the gratifying improvements in mill products which resulted from the new procedure. The process has been placed in operation at the La Corne mine of the Molybdenite Corporation of Canada. This mine was operated during the war by Wartime Metals Corporation, and, earlier, by the Molybdenite Reduction Company, which installed a small plant. The property is situated on the highway from Amos to Val d'Or, Quebec. The claims held by the Company are at the boundary between La Corne and Vassan townships.

Jan 1, 1947

By G. A. Johnson

Basic management principles will be discussed (as they apply to minerals education efforts), especially in light of the changing nature of volunteerism in today’s society. Also, the “minerals education tree” will be presented, along with public opinion / public policy realities.

Jan 1, 2001

By Osvaldo A. Bascur

Most mining and metallurgical plants have developed predictive maintenance policies based on statistical analysis and special techniques, like vibration analysis, oil and lube analysis for critical equipment. Process control strategies have also been installed in several metallurgical sites. These control strategies require instrumentation maintenance from local personnel. The availability of real time and process history to identify the most critical part of the processing system from mechanical integrity is a must for global plant optimization. Specialized performance control monitoring algorithms are required to justify their existence and contribution to the bottom line. Emerging technologies are combining these techniques into a single total plant system. Tools are required to assist in troubleshooting and adapting these process control instruments and strategies. The key is the plant equipment and process control availability and utilization rather than just maintenance.

Jan 1, 1997

By J. Dean Warner

In 1984 and 1985, as part of its critical and strategic minerals studies, the Bureau of Mines investigated lode and placer tin occurrences near Rocky Mountain (Lime Peak), in east-central Alaska. The lode occurrences consist of mineralogically complex, generally fault-controlled veins, and contain an average of approximately 0.05 pct Sn, as cassiterite. Beneficiation testing of two bulk samples of the vein material produced concentrates containing 65 and 59 pct of the total tin values at grades of 0.35 and 13.9 pct, respectively. Although as much as 30 million short tons (MMst) of mineralized rock containing up to 20 MMlb Sn may be present, the grade of these occurrences is too low to be considered economic at this time. Trace amounts of cassiterite were also identified in surface samples of glacial out-wash gravels collected along North Fork Preacher Creek, which partially drains the area of tin lode deposits near Lime Peak. Low tin grades in the samples do not account for the former erosion of a large volume of lode tin mineralization from near Lime Peak; higher tin grades may be present in gravels closer to bedrock.

Jan 1, 1988

Mining and oil industry representatives are scheduled to testify May 15 at hearings on the Simpson bill to extend the Reciprocal Trade Agreements Act, Several Congressmen have introduced bills to extend present trade agreements without modification. Price of copper appears to be stabilizing at 30[] per lb, after a period where market price ranged from 27 to 34[]. Copper offerings from abroad were finding no takers at 30.24[] per lb late in April.

Jan 5, 1953

By W. Burr Bennett

The prestressed concrete industry in particular, and the precast concrete industry to some extent, are rank newcomers to the concrete construction field compared to the cement, ready-mixed or concrete masonry industries. This young industry reflects its youth and vigor in its enthusiasm, optimism and the belief that it can reach any goal it chooses to set -- and it is setting its sights high. The prestressed and precast concrete industry fully expects to become the major structural and architectural material by the 1980's. Before exploring how the industry expects to reach this goal, a brief look at the origins and the growth of the industry may be useful in an evaluation of the feasibility of this goal. It was always recognized that concrete, strong and efficient for supporting loads which cause compression, was weak and inefficient when used to carry loads which induce tension. Thus the reason for reinforced concrete in which the concrete efficiently carries the compression in a flexural member while low grade steel bars reinforce the concrete in the areas 'of tensile stress. (Fig. 1). The steel being relatively inexpensive, can passively, but quite effectively carry tensile force while the concrete carries compression. The concrete in contact with the reinforcing also protects the steel from corrosion and acts as insulation to provide a superior "built-in" fire resistance. The major disadvantage of reinforced concrete relative to its main competitor, steel, is its weight in relation to its load-carrying capacity. Reinforced concrete systems, such as waffle slabs, I-beams, thin shells, etc. ,

Jan 1, 1971

By Sotiris N. Kamenopoulos, Zach Agioutantis

Rare earth elements (REEs) are considered critical minerals for industrial and defense sectors. REEs are not as rare as the word “rare” portrays; yet, the exploitable and/or profitable deposits of REEs may be found only in certain geographical areas. The political and social conditions characterizing these areas may not always be in favor of mining operations. These conditions are imposing the need for extra consideration on the geopolitical constraints prior to any decision-making and before any mining project begins. This study assesses the risk related to mining projects for areas that feature REE deposits based on a geopolitical viewpoint. Probable ranking differences between the current assessment and a 2015 assessment are discussed. The comparative indicators used and the appraisal procedure applied in this comparison are based on a number of different geopolitical indicators. Several ranking changes occurred between 2015 and 2019.

These proceedings consist of an overview of the underground metal and nonmetal mina fire protection research currently being conducted by the Bureau of Mines. The following papers address the areas of prompt, reliable fire detection, fire planning and warning, fire suppression, and personnel protection. Selected topics are included here that cover fire protection systems for shafts, underground fueling areas, and mobile underground mining equipment; spontaneous combustion, improved stench, and product-of-combustion fire warning systems; computer-aided ventilation modeling; fire doors; and an investigation of fire hazards in mine timbers. The projects described provide a current documentation of problems being addressed.

Jan 1, 1981

By F. F. Roberto, E. Kirby, A. R. Marchbank

The application of biologically assisted methods for metal extraction in the mining industry has a long history, but development of modern techniques has been relatively slow. There is, however, a resurgence of interest in the industry with the recent development of methods to successfully treat base metals concentrates. Two major pilot plant programs for treatment of chalcopyrite concentrates have been initiated in the past year and results from one are beginning to be released. This paper provides an overview of methods that have been applied in the past, from the earliest deliberate applications of the technology, through the copper and uranium heap and dump leach applications, the more highly engineered agitated tank leach gold applications and the developments currently taking place in the industry.

Jan 1, 2003

By Ronald B. Hollenbeck

The value of mineral production in Alabama continued to increase and reached a new high of $260 million, 3 percent above the previous high established in 1967. Record high values were reported for bentonite, crushed marble, lime, miscellaneous clay, portland cement, salt, sand and gravel, and scrap mica. The value of coal, total cement, petroleum, and stone accounted for 87 percent of the State's total value of mineral production. Alabama ranked second among the States in the production of bauxite and scrap mica and third in kaolin, masonry cement, and native asphalt.

Jan 1, 1970

Ground falls (roof and rib) have historically been responsible for nearly 50% of all fatalities in bituminous underground coal mines. In recent years, the number of some annual ground fall fatalities has approached zero, indicating that significant progress has been made. On the other hand, the twin disasters at Crandall Canyon in 2007, in which nine miners perished in violent coal bumps, provided a stark reminder that complacency is premature. One important success has been a great reduction in the number of miners killed inby roof supports. Throughout the 1990s, these accounted for nearly half of all roof fall fatalities, but there have just been two inby incidents since 2005. Progress has also been made in pillar recovery, where there has been just one fatal incident since 2005. On the other hand, more than 300 miners continue to be injured each year by rock falling from between supports and 100 more are injured by rib falls. Together, these two categories also account for a large percentage of recent ground fall fatalities available technologies such as roof screen, rib bolting and inside control roof bolters could reduce injury and fatality rates if they were used more widely. Further advances in these areas will likely be the next big advance in ground control safety.

Jan 1, 2011

By Nan C. Jensen

Modern high-temperature metallurgical processes have created a demand for raw material for furnace parts and lining that not only will with-stand high temperatures is but will not react with the substance being melted in the furnace. Spark-plug insulators, laboratory ware, tanks for the glassmaking making industry, and saggers and kiln furniture for the chinaware and pottery trades also must be made of materials hat have high melting points. Among the minerals that can be employed for such refractory uses ore those commonly known as the "sillimanite group' -kyanite, andaluste, sillimanite, and dumortierite - and the allied minerals topaz and pinite. Consideration of the occurrence, properties, qualities, uses, and sources of supply of these commodities and the markets for them constitute the subject of this paper. General Features of Kyanite and Related Minerals Kyanite, andalusite, and sillimanite ire composed of three elements - aluminum, silicon, and oxygen ? and are called aluminum silicates. The have

Jan 1, 1943

By Hugo de León Carvalho Cedro

O presente trabalho tem como objetivo avaliar os efeitos da degradação da superfície de lentes de contato via métodos ópticos. Sendo biomateriais, as lentes estão em contato direto com estruturas sensíveis do corpo humano e seu uso surge da necessidade de reduzir enfermidades, propiciando melhora da acuidade visual e proteção ocular. Outro aspecto relevante é que as lentes se tornam uma nova estrutura refrativa de entrada da luz no globo ocular, e desse modo devem manter características de transmitância compatíveis com a córnea. Com o uso das lentes, é esperado uma degradação natural das propriedades ópticas e superficiais da mesma. Para avaliarmos essa degradação, foi planejado um experimento com um ensaio de degradação. O ensaio de degradação visa comparar o efeito de diferentes soluções simuladoras sobre a superfície das lentes tóricas: solução extrema de acetato de potássio 5% pH5, solução fisiológica usada pelo fabricante do tipo Boston Simplus multiação e solução de água ultrapura obtida de um dispositivo milli-Q (controle). O efeito da degradação foi analisado através do estudo das variações da topografia e da transmitância da lente.

Oct 30, 2017