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By S. H. Ash

The paramount responsibility of Government is to protect the general welfare. One of the chief functions of the Bureau of Mines is to investigate and publicize methods of increasing safety and efficiency in mining operations. In an industrial civilization, energy resources constitute the foundation of a sound economic structure (14).4/ Coal is only one source of energy, but it provides more than half the energy consumed in the United States.

Jan 1, 1946

By F. L. Jackson

The large scale transportation and storage of sulphur in the liquid state is a relatively new development, but is really only a logical extension of old mining and processing techniques, It is not known who the first person was to win a relatively pure sulphur from ore by melting, but this method was commercially used at least two hundred years ago in Sicily and is still in use today. The Frasch process of mining was invented over sixty years ago, and the development and improvement of-liquid sulphur pumping and handling techniques has paralleled the growth in the Frasch mining industry. During the last fifty years, improvements in the technology of using sulphur have included the premelting of sulphur prior to its being burned for acid production or conversion into CS2 and other compounds. Yet, until fairly recent times, sulphur produced as liquid has been solidified into large blocks at the producing point, broken down by blasting or with mechanical equipment, and shipped in bulk form as a solid.

Jan 1, 1962

By R. J. Chase, C. Davies

"Abstract- The Merelani graphite-tanzanite deposit is located in northeast Tanzania, 14 kilometers south of Kilirnajaro International Airport and in close proximity to the towns of Moshi and Arusha . The graphite mineralization is hosted by relatively undeformed linear Proterowic metasedimentary gneisses, several of which have been subjected to hydrothermal alteration resulting in tanzanite mineralization. Exploration work comprised detailed geological mapping coupled with pit and trench channel sampling and a subsequent 1500 meters of diamond drilling. In addition, metallurgical tests have shown the graphite to be of unusually coarse flake size, crystallinity and high purity.Feasibility studies have shown the economic viability of a major coarse flake graphite deposit with the measured resource to 50 meters in excess of 9 million tonnes assaying over 8o/o graphitic carbon . Production is due to start by the end of the first quarter of 1994 with the processing plant design capacity initially set at 15 000 tonnes per annum.ln addition to graphite production, tanzanite will be produced through selective mining within the graphite open pit in the upper horizon and from underground workings within the lower horizon.The Merelani graphite-tanzanite deposit will be the first major orebody to be exploited through means of private funding since Tanzania gained independence."

Jan 1, 1994

By J. Wesley Atkins

In considering the importance of lease management and administration, I have decided to approach the topic, Lease Default and Eviction: Action or Reaction, as a three phase presentation dealing with mineral lease administration and management, past, present and future. Though the title may border on the dramatic, it illustrates the real consequences of alternative approaches to property management viewed from my experience in the evaluation, development and implementation of a number of such systems and services in my current position as president of Talco Group Corporation. First, though, let's take a moment and set the stage by giving a few actual examples of why a pragmatic approach is needed in this particular area.

Jan 1, 1983

By J. H. H. Chamberlin

"In the Introduction the author briefly discusses the company history as it relates to the development of its contracts with the Japanese steel mills. The main part of the text describes how Coleman Collieries Limited approached the problem of mining coal profitably in thick, steeply inclined seams. For many years a basic room-andpillar system was worked by conventional methods. Main roadways were driven on strike across the mineable area. These roadways acted as haulage routes for coal, materials and men. Rooms were developed to the rise of the main haulage route by pairs of men using air-operated hand picks. As these rooms advanced the miners would lay and extend a sheetiron chute down which mined coal would gravitate to a controlled loading point, where it was loaded into trains of mine cars. Connecting roadways or ""OFFS"" were driven at predetermined intervals between adjacent rooms, forming pil1ars or blocks. Extraction of the blocks followed on a line conducive to good strata control some distance behind the developing rooms. A need for higher productivity, expansion of the operations and a scarcity of qualified miners resulted in the company deciding to mechanize its underground mines. Joy 6 CM continuous miners and 10 SC shuttle cars were selected as being machines that could reasonably negotiate the problems associated with the pitching seam. The equipment, nonetheless, has definite limitations and Coleman therefore developed a modified version of the room-and-pi11ar system such that the miners and cars could work on cross pitch. In the area described, main roadways were driven to the rise on an average gradient of 12 degrees. Panels, which consisted of two parallel roads with interconnecting cross-cuts, were then developed on strike to a boundary point. Blocks formed in the development of the panels were subsequently extracted on retreat. Problems associated with each phase of the operation are thoroughly discussed, together with roadway support methods and equipment used for the conveyance of coal and materials."

Jan 1, 1972

By L. Michael Kaas

In recent years a number of data processing and analytical techniques have proven to be useful to engineers and geologists in various segments of the mineral industries. Petroleum companies were among the first to utilize the computer to store well data files and to analyze that data for exploration purposes. A few years later, metal mining companies began to apply the same basic computer methods to problems in mineral exploration, ore reserve evaluation, and open pit mine planning. Because of the increasing complexity of planning for coal mines and land reclamation, a case study was undertaken to evaluate the usefulness of computer techniques to assist mining engineers and geologists in mapping coal deposits, evaluating coal reserves, strip mine planning and land management. The data used in the study was provided by the Illinois State Geologic Survey. This paper describes some of the results of that study. First, considerations for the development of a computer data base for coal deposits are presented. Next, a series of analytical techniques for processing the data is described. Finally, the case study is presented to illustrate how the coal data base and the analytical techniques could be used in actual practice.

Jan 1, 1973

By James J. Scott

To the safety engineer, mine planning engineer, and mine inspector associated with an underground operation, stability of the underground structure is of the utmost importance. In the United States in 1961 rock falls killed 167 miners, crippled many more, and cost the industry a fortune in lost equipment and production. Much research has been carried on to try to find ways to eliminate this loss of life and property. Within the past few years the interest in rock mechanics as a science has been at its highest point, Private industry, government agencies, universities and foundations have launched studies to gain a better basic understanding of the stability of underground openings.

Jan 1, 1966

By E. R. Rodriguez

Improved practice resulting from recent changes in the method of supplying compressed air and in pneumatic drilling equipment used in secondary drilling and in development work at the Morenci mine of the Phelps Dodge Corp., has resulted in improved safety conditions, as well as in a reduced cost per foot of drilling. A large stationary compressor installed outside the mining area and the compressed-air pipelines in the mine were replaced by portable compressor units. A self-propelled, self-contained drilling unit was obtained for drilling large footages where short moves were involved. Large wagon-drill units were replaced by faster and lighter drill machines and conventional bits by carbide insert bits. The safe practices employed in air drilling and in the related blasting and scaling operations have contributed to an excellent safety record at this mine. The complete sets of instructions listed in the company codes of safe practice aid materially in training employees.

Jan 1, 1956

By Yukio Ishikawa

Sumitomo Metal Mining Co,. Ltd. (SMM) has been producing 22,000 t/y of electrolytic nickel at Niihama by nickel matte electrorefining process since 1970. Although the matte electrorefining is an established process and the productivity has been greatly improved in the last 20 years, SMM has intensively developed the chloride process for the nickel production since 1970's. The nickel and cobalt refining process involving solvent extraction and electrowinning from the chloride solution has been successfully developed for the treatment of the mixed sulphide in 1975. The first application of chlorine leach to the anode slime has been succeeded since 1986. Based on those technology, the matte chlorine leach electrowinning process (MCLE) has been developed as an alternation to the relatively old technology of matte electrorefining. The new process offers significant cost down and excellent quality of the product. In 1986, the feasibility of MCLE was confirmed by the test work using the integlated pilot plant. The innovation of the chlorine leach process has been undertaken by this work. The new refining process can be divided into three stages including chlorine leach stage, purification stage and electrowinning stage. More than 99 % of nickel was extracted in atmospheric chlorine leach. Although copper ion was used for electron carrier in the chlorine leach, the excess copper from the feed matte is bled off from the leach circuit by de copperizing electrolysis. The copper ion of the pregnant solution is fixed on nickel matte by the cementation reaction. The nickel matte containing copper is processed in the chlorine leach. In the purification circuit, cobalt, iron and other impurities were removed from the nickel chloride solution. The nickel chloride solution is then fed into the electrowinning cell. Based on the process established, the new plant with a capacity of 330 t/M electrolytic nickel was commissioned in order to obtain the engineering data for design of the full scale plant in 1989. The performance of the plant was fully satisfied and the new process demonstrated the potential application of modern process control.

Jan 1, 1992

By J. Iannicelli

Spray drying is the principal drying method used in the production of over six million tons annually of beneficiated kaolin in Georgia. Thirty-three dryers in the Georgia Kaolin belt comprise the highest concentration of large tonnage spray dryers in the world. The steady growth of spray drying in the U.S. kaolin industry is paced by advances in design and development of large spray dryers which have led to large scale new applications in mining and related industries.

Jan 1, 1982

By M. Y. Levesque

The Australian Government?s Energy Efficiency Opportunities (EEO) program launched in 2006 obliges companies that use more than 0.5 PJ (petajoule) or roughly 139 GWh (gigawatt hour) per year to conduct an energy assessment in order to identify measures to improve energy efficiency. The opportunities identified by the mining sector were assembled in the Mining Significant Opportunities Register that permitted companies not yet embracing and adopting an energy management program to see what those who are, were doing and how much energy was saved, and helps disseminate best practice. The measures can be filtered by company, year, category or equipment type. The creation of a central repository of energy efficiency initiatives is valuable but this existing database could be improved; fields identifying the energy and carbon emission savings associated with a given initiative are a surprising omission. Consequently it does not permit the relative effectiveness of different measures for energy and carbon reductions to be readily assessed. A review of energy management efforts implemented in the mining industry, published in peer reviewed journals, corporate sustainability reports or industry publications during the last 40 years has revealed many examples of best practice. However, the lack of a standardized reporting framework in any of these sources has made it difficult to assess the effectiveness and compare the adopted energy management measures ? just as is the case with the Australian register. In an attempt to address these issues, an improved database structure has been created for energy management measures from the mining industry which identifies energy and financial savings arising from energy management initiatives, classifies applications to specific processes or equipment, and recognizes leaders in the mining industry with respect to energy management. The structure of the register includes the key data relevant to energy management in mining that is absent in the Australian version. The mining industry energy management database has been made available in the public domain where stakeholders can examine the best practice examples. Mining energy champions may also contribute to the register by providing case studies; a standardized entry template affords a quality assurance dimension that is absent in other reporting initiatives. Adoption of this database with its standardized reporting mechanism will enhance transparency of the mining industry in energy matters and help it maintain its social license to operate.

Aug 1, 2013

By R. L. Roller

In recent years, there have been many articles and papers written on the use of specially designed belt conveyor systems in mining operations, either economic studies or actual experience. These papers generally conclude that the use of these systems can reduce overall costs from 10% to 40% over conventional methods using general purpose equipment (truck/shovel, scrapers, etc.). However, they also generally conclude that conveyor systems are inflexible and capital intensive. With the increasing cost of mobile equipment, the capital cost conclusion is losing steam, particularly when the costs of maintenance shops, road and ramp construction and other related start-up costs are thrown in. Attention here will be focused on answers to flexibility related questions, but first, a look at costs in general. Basic production economics tell us that when we have a small job to do, it is cost effective to use simple, low cost, general purpose tools which will have a minimum impact on total cost. It also tells us that when we have a large project, we can employ methods using special, relatively expensive production tools. Figure 1 illustrates what occurs on projects, of different sizes, with various quantities of production. With small quantities of work, the cost per unit of work starts out much lower using general purpose equipment, rather than using special purpose methods and equipment. However, at a relatively low quantity of work, the cost hits a lower limit and, regardless of how great the quantity of work, the unit cost can never go any lower.

Jan 1, 1985

By K. C. Watts

The Silver City mining region is located in Grant County, southwestern New Mexico (Fig. 1). This area is well known, having produced large tonnages of base and lesser amounts of precious metals over the past several years. Mining within the region continues today, as well as exploration activity, which seems to have been on the increase since the recent discovery of a large skarn-associated Zn-Pb-Cu replacement deposit near Pinos Altos, a mineral district within the region (McKnight and Fellows, 1978). Because the Silver City area contains a number of mineral districts and retains promise for additional deposits, as suggested by widespread hydrothermal alteration and favorable igneous rocks, it was selected as the focus of two independent geochemical studies, both seeking to enhance anomaly-to- background contrast in order to improve our abilities to detect blind metal deposits or subtle manifestations of near-surface occurrences. The first of these independent studies involved the systematic sampling of those secondary Fe-Mn oxides that occur within coatings, selvages, and fault fillings, and then the selective extraction of these oxides from the host-rock matrix by chemical methods. The second study sought to isolate clastic Fe-Mn-rich materials from the heavy fraction of stream alluvium. The ultimate source of the clastic Fe-Mn oxides is presumed to be the same coatings, selvages, and fault fillings sought by the direct sampling of joints, but has been transported as a result of lateral erosional processes.

Jan 1, 1981

By G. Upadhya

Of late, solidification modeling has progressed considerably to emerge as a viable simulation tool for the foundry engineer. A wide variety of tools exist in the commercial market to cater to the various needs of the design/ foundry engineer. In fact, recent developments in the area of solidification modeling have been so rapid that a comprehensive review of the state-of-the-art is very much needed. In this paper, an attempt is made to summarize the various issues of solidification modeling, at the same time addressing the historical evolution of the subject. The various phenomenological issues covered in this paper include: heat transfer, fluid flow during mold-filling, solidification kinetics and microstructural evolution, quick-analysis schemes for approximations, porosity prediction models, and the phenomena of fluid flow in the mushy zone. Modeling issues related to the development of solidification stresses which lead to defects such as hot tears and the development of artificial intelligence concepts in the area of rigging design are also discussed. Due emphasis is given to the various phenomena which add to the complexity of the whole subject, and the various alternatives available for solving a particular problem. For example, the heat transfer problem can be approached by the use of simple modulus schemes or by solving the conduction equation to obtain a more accurate temperature distribution. Similarly the microstructural evolution can be handled in a deterministic way by use of nucleation and growth models, or in a probabilistic way by use of empirical models. The main goal of this paper is to put the multi-faceted problem of solidification modeling in proper perspective so that it can serve as a guide for future developments in this area.

Jan 1, 1994

By J. V. Bymark

It is the intent of this paper to discuss the autogenous grinding circuit at Hibbing Taconite. The scope of the presentation includes; a brief history, the process flowsheet and the steps taken to improve mill productivity, availability and metallurgical performance. Hibbing Taconite is located near the center of the Mesabi Range in Northern Minnesota 100 miles from the Canadian border and 80 miles north of the Lake Superior Port Cities of Duluth and Superior. A 105 mile railroad connects us with the port of Superior, Wisconsin, where our pellets are loaded into lake carriers for lower lake destinations. It is worthy to mention the Mesabi Range's most famous landmark which is immediately to the south of our mine area. This is the Hull Rust Mahoning Mine which operated until the mid-1970's producing more than 700 million tons of red ore between 1893 and 1973.

Jan 1, 1985

By J Skousen, C E. Zipper

"Prior to the 1950s in the USA, surface coalmines were generally left without any reclamation. As government regulations advanced, mine operators were required to backfill the area and plant grasses or trees. After the federal Surface Mining Control and Reclamation Act (SMCRA) was passed in 1977 in the USA, mine operators were required to conduct pre-mining analyses of the site and to designate a land use that could be achieved after the mining. Common post-mining land uses in the USA are: agricultural uses such as prime farmland reclamation with crops, hayland and pasture, and biofuel crops forestry wildlife habitat building site development.Provisions and regulations for each post-mining land use were developed and practices to achieve successful and sustainable land uses were established. Post-mining conditions should provide ecosystem services and produce lands capable of supporting societal needs in the future.CITATION:Skousen, J and Zipper, C?E,?2014. Post-mining land use options in the Appalachian coal mining region of the USA, in Proceedings Life-of-Mine 2014, pp 153–164 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 16, 2014

By Allan M. Hale

The central Florida phosphate industry is not a recent development. The first phosphate mining occurred in approximately 1888 (1). Many of the original mining companies were "wildcat" operations operated with rapid phosphate extraction as the sole purpose and no long-term commitment to development. Many of the early pioneers were ill-equipped to mine phosphate at either a practical or economical level; as a result many of these early companies "folded" after only a brief period of operation. However, as these early companies went out of business, several large companies developed, expanded their mining territories bought up the folding companies and by 1903 (little more than 10 years after the first mines were started), approximately 37 of the original 60 mines were control- led by three major companies (1). In the early period, mining reclamation was nonexistent. The mined out areas were left to revegetate and reclaim "naturally" over the period of many years. Reclamation practices were only started relatively recently and the various reclamation techniques developed and used in the past have continued to be employed with varying degrees of success through the present time. The reclamation techniques used in the past and currently include land and lakes restoration, sand tailing reclamation, slime ponds reclamation and overburden fill.

Jan 1, 1980

By Miche1 Dagbert

In most open pit operations mining porphyry type deposits, production planning rests on an are reserve inventory block file which is derived from diamond drill hole data. With such a practice, the way by which block values are generated is critical and in the recent years many studies deal with the comparison of different estimation methods for block grades (Mueller, E. (1), Knudsen et al (2) (3), Barnes, (4), Williamson and Mueller (5). Typically in such studies, one selects a bench or a group of benches where there is a "sufficient" number of blast holes (BH) with assay values in each of the blocks (generally 30.5 x 30.5 m (100 x 100 ft) or 15.2 x15.2 m (50 x50 ft). Then the arithmetic mean of the BH values in each block is computed and it is assumed to represent the real block grade against which different estimated values are compared. However it is sometimes observed that the variation of these BH values within a block is high and that their arithmetic average may significantly differ from the real average grade of the block (Barnes (4). The problem of the precision of the mean BH grade in a block has been examined by Williamson and Langlois (6) in an experimental way. They strove to find a better estimate of the average block grade than the mean BH grade but their results were not conclusive. The purpose of this study is to investigate the same problem within the frame of geostatistical models (David (7). Besides practical results obtained with these models, two general points are emphasized and illustrated in the text. First, "good results" are obtained if "good geostatistics" is done (David et al (8).

Jan 1, 1978

"Block caving is the preferred underground mining method to profitably extract massive, low-grade orebodies; however, lack of cave access inhibits understanding the rockmass response to mining, which is needed for safer, more productive operations. Combining large datasets from multiple sources with virtual reality scientific visualization (VRSV) is an alternative method for understanding complex cave behaviour, by providing virtual access to the cave. A customized VRSV module was developed at UNSW Australia to investigate rockmass response to undercut developments at a case-study block caving operation. Time/sequence effects are investigated in rockmass response to blasting, which is an important factor in hard-rock mines.RÉSUMÉ La méthode d’extraction souterraine par blocs foudroyés est la méthode préférentielle pour extraire rentablement des gisements massifs à faible teneur. Toutefois, le manque d’accès à la chambre restreint la compréhension de la réponse de la masse rocheuse à l’exploitation, ce qui est nécessaire pour obtenir des opérations plus sécuritaires et plus productives. La combinaison de grands ensembles de données de multiples sources avec la visualisation scientifique par réalité virtuelle (VRSV) constitue un autre moyen de comprendre le comportement complexe de la chambre en fournissant un accès virtuel à la chambre. Un module de VRSV sur mesure a été développé à l’Université de Nouvelles-Galles du Sud (UNSW) en Australie afin d’étudier, dans une étude de cas d’une exploitation par blocs foudroyés, la réponse de la masse rocheuse aux développements de galeries de sous-cavage. Les effets de temps/séquence sont étudiés dans la réponse de la masse rocheuse au sautage, ce qui est un facteur important dans les mines de roches dures."

Jan 1, 2016

By A Horne, Z Graszkiewicz, D Dettrick, R Evan, B Neal

"Most of VictoriaÆs rivers and aquifers are already fully allocated or reaching full allocation. In regions without a well-established water market, access to water entitlements to facilitate new development is limited. In areas with established water markets, mine developers face an undue cost burden in circumstances where they are only planning to consume a fraction of the water entitlements that they purchase. The challenge for water managers is to ensure protection of water resources and other water users without creating an unnecessary disincentive for those types of developments that return most of the water that they take from water sources. The opportunity for development of a mine is explicitly linked to a particular location and must be developed where a resource is located or it cannot be exploited at all. Regulatory arrangements that facilitate development may have a positive impact on economic development, particularly where water availability is a potentially limiting factor. Net volume licensing has the potential to allow increased economic outcomes through improved licensing of access to water. Net volume licensing differs from traditional water licensing in that it authorises access to water on the basis of ænet useÆ rather than æthe gross volume takenÆ. This paper asks under what conditions net volume licensing is likely to be feasible and effective. In particular, the paper examines the information and accuracy requirements to allow net volume licensing decisions to be made. This work is based around five case studies in Victoria that were used to examine the potential for net volume licensing for mines and quarries. Assessing a potential net volume licensing arrangement requires the regulating authority to have an understanding of the inputs and outputs of water to a site. In contrast, assessment of take and use licences consider only a single input. It was concluded that the conditions that lend themselves to net volume licensing include: well understood water inputs and outputs, including appropriate accuracy of information where the location of site water inputs and outputs are the same where the timing of extraction and discharge can be managed to minimise impact on the water resource.A key remaining challenge is establishing an accounting framework that allows net volume licensing under current water resource limits. CITATION:Graszkiewicz, Z, Horne, A, Neal, B, Evan, R and Dettrick, D, 2013. The practicalities of implementing net volume licensing of water use in mines and quarries - a discussion based on Victorian case studies, in Proceedings Water in Mining 2013, pp 241-250 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 26, 2013