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By D Connelly

As the resources sector becomes tougher with rising costs and cyclical metal prices, mining companies need to continue to reduce their costs and do more with less. Many new resource projects fail to come in under or on budget based on Feasibility Studies. Particularly, capital expenditure (CAPEX) proves difficult to achieve for resource projects. A number of resource projects have failed because of aggressive plant CAPEX cost cutting resulting in projects with no surge capacity and are unable to achieve design throughput. In addition, the plants are not operable because of the omissions. In recent times many businesses have also experienced the "costs" of simply implementing aggressive operating "cost cutting” measures as a strategy for solving business performance problems. This paper looks at technology driven, employment related, luxury cuts, department cuts and restructuring cuts. In the past companies used an incremental approach based on the use of past budget information as an integral part of the budget construction process going forward. The use of performance reports and Management Information Systems (MIS) is examined along with the role of continuous improvement in achieving sensible cost cutting.

Aug 8, 2011

By J. S. Laskowski

Anisotropic minerals are important constituents of many ores. This group includes both valuable minerals (e.g., molybdenite in Cu-Mo ores) as well as gangue minerals (e.g., talc in platinumbearing sulphide ores in South Africa, graphite in Cu-Ni sulphide ores in Canada, chrysotile in Ni sulphide ores in Australia, and clay minerals in all types of ores). Aqueous suspensions of anisotropic minerals exhibit different properties than suspensions of isotropic minerals. The presence of anisotropic minerals in flotation circuits affects the flotation process.

Jan 1, 2012

By P. Clifford

FIPR-sponsored research will playa critical role in enhancing the competitiveness of the Florida phosphate industry as ore grade declines and environmental restrictions tighten. FIPR's program seeks to improve surface mining and pipeline transportation while reducing the energy cost for pumping phosphate matrix. The development of a reliable on-line analyzer and a modern process control strategy will result in improved processing efficiency. Significant improvement in overall efficiency will also be realized as the industry adopts column flotation technology. Economic acidulation of high-Insol rock will allow the industry to adopt simplified flotation flowsheets thereby reducing operating costs. Various applications of phosphogypsum would save the industry millions of dollars in constructing and closing gypsum stacks.

Jan 1, 1998

By L Brodie-Hally

In the early-1990s, Tad Golosinski, the former the head of mining department at WASM participated in a review mining engineering courses in Australia. The review team asked various industry executives what subjects they thought graduates needed to be taught. Tad made the comment to me that the more senior executives thought that history and ethics were very important. The outcome was that the mining engineering courses were required to contain at least five per cent content dealing in ethics. The course was to be modified to reflect this. Tad thought at the time the students would think that subjects dealing in history and ethics came from retirees and professionals that were over the hill. So let me talk to you today about ethics.

Jan 1, 2002

By Louis J. Sousa

In November 1989, the U.S. Bureau of Mines sponsored a 2-day conference to stimulate thinking and discussion about changing materials technologies and implications for the Government's materials information programs. On the first day of the conference, speakers provided overviews of developments occurring in each of the major materials groups. Emerging technological developments, applications, economic and national defense significance, intermaterial competition, and potential market growth in advanced plastics, polymer composites, ceramics, metals, and electronic materials were described. In general, the speakers forecast advanced materials market growth rates in excess of overall gross national product (GNP) though high costs will tend to limit growth outside of aerospace, defense, electronics, medical equipment, and other typically high value-added businesses. On the second day, a wide range of speakers representing several facets of the materials community described how advances in materials technology are creating a need for new types of data, statistics, information, and analysis. Reflecting the speakers' broad range of organizational, professional, and personal perspectives, an array of information needs was identified. Most requirements, however, seemed to fall into one of five major categories: Federal materials research activities, material standards, market and economic information, health and safety, and public policy.

Jan 1, 1990

By John W. Chandler

The property of the lava Cap Gold: Mining Corporation is in the Nevada City-Grass Valley mining district about 5 miles east of Crass Valley, Calif. At present (July 1940) the plant is mining end milling about 390 tons of gold-silver ore a day; about 310 men are employed. This paper describes the mining methods used and presents mining costs for 1939, when 60,704 tons were mined by cut-and-fill stoping and 55,676 tons by square-setting.

Jan 1, 1941

By A. E. Halim, J. F. Brune

The 2006 Sago, Darby, and Aracoma mine disasters in the United States (US) forced the US government to implement the 2006 MINER Act and additional regulations that require all US underground coal mines to install and maintain refuge chambers to manage entrapment emergencies, in particular, fires and explosions. However, there is a debate on whether barricading in refuge chambers is a good strategy to survive such emergencies. Australian coal mines are not required to use refuge chambers and, instead, have adopted a strategy that focuses on instructing and training miners to self-escape to the surface. This paper analyzes merits and problems of using refuge chambers and self-escape to the surface to manage emergencies in fires or explosions in an underground coal mine. The authors found that the use of refuge chambers may not be the best strategy during extensive fires or when multiple explosions happen. In these situations, mine rescuers are unlikely able to extract miners who are sheltered in chambers and conversely, self-escape may save more lives than sheltering. Chances for successful self-escape are further improved by regular, externally assessed training such as Level 1 Emergency Exercises required in the Australian State of Queensland. These exercises put pressure on mine operators to ensure and maintain the effectiveness of their emergency management system.

The epizonal Ag-Pb-Zn vein deposit at San Bartolome is characterised by a base-metal sulphide assemblage containing the spectacular development of interpenetrating, bladed networks of pyrrhotite which have been replaced by marcasite and pyrite. A similar assemblage displaying the same crystal habits and textures are also a diagnostic feature of the Sn and Sn- Ag deposits of Bolivia. On this basis, it is reasonable to conclude that both deposits were formed from fluids of similar nature and origin. Although no economic accumulation of Sn is known in San Bartolomr, further comparison of the geologic setting, age, mineralogy, fluid inclusion data and magmatic association of this deposit with the Bolivian systems has highlighted additional similarities consistent with a hypothesis that more extensive Sn mineralisation might exist in the San Bartolomd area.

Jan 1, 1995

By Paul Guliov

Industrial clays, including a variety of bentonites and kaolinbased clays in southern Saskatchewan are hosted by Late Cretaceous and Early Tertiary sediments. Ofparticular significance are the deposits of swelling bentonite in the Cretaceous Bearpaw Formation and the kaolinitic clays of the Cretaceous Whitemud and Paleocene Ravenscrag Formations. Swelling bentonite is currently produced in the Wilcox-Truax area by Canadian Clay Products Inc. and yields at least seven different commercial products for a variety of applications. Kaolinitic plastic clays, including ball clay, stoneware and earthenware clay, as well as kaolin in southern Saskatchewan, have a long history of development and use. Products include common and face brick, refractory bricks and other shapes, chinaware, pottery, sewer pipe, chimney flue linings and tiles. Currently clay production is for out-of-province brick manufacturing and for pottery. Recent research and improved technology combined with expansion in certain areas of the global clay industry generally hold promise for a resurgence of a clay-based industry in Saskatchewan. Products of particular promise include: clay tiles; kaolin fillers and extenders; and aluminum as well as related by-products from kaolinitic clays based on the carbochlorination process.

Jan 1, 2001

By P A. Tilyard

There have been enormous changes in mineral processing in the past four decades. For example grinding mill power has increased by an order of magnitude, regrinding is done to -10 microns and flotation machines are 100 times bigger. Operating staff have unprecedented opportunities for online monitoring and performance control of mineral processing plants. Sophisticated instruments can provide a plethora of data characterising the mineralogy and surfaces of particles. Digital computers allow complex calculations on huge amounts of data including modelling and simulation of machine and plant performance. However, all these changes have not necessarily lead to better metallurgical results. An analogy can be drawn with the thoroughbred racing industry in Australia. Significant advances in scientific knowledge in animal genetics, physiology, biomechanics and nutrition applied to the business have resulted in only a two per cent reduction in winning times for the Melbourne Cup and Caulfield Cup since the 1920s. A critical look at some mineral processing metrics suggests similar failures to improve performance despite putting in more resources. In fact certain parameters such as operating times and plant start-up performance are considered to have remained static or even deteriorated. There has been an emphasis on 'process' at the expense of 'outcomes'. The industry's strength has been in finding technical (or 'hardware') solutions while its weakness has been at the people end of the business in maximising and consolidating the gains from the technologies. Some trends in plant design over these years have exacerbated the apparent deskilling of operating and technical staff. Despite unparalleled options for communications, some staff are embarrassingly uninformed about technical developments in their fields. The 'boom and bust' cycles of the industry, together with trends in tertiary education and the effects of fly-in, fly-out (FIFO) operations, raise serious questions about the sustainability of human capital in the mineral processing sector. This paper by two experienced mineral processing engineers, with contributions from other senior practitioners, reviews these trends. While there may be an element of 'the older we are, the better we were', it is an attempt to identify the issues and propose solutions.

Jan 1, 2009

By Dan S. Nilsson

Small-scale mines are today expected to provide much of the increased production of metals, industnial minerals and coal this country demands in the future. But what is the size trend in the mining industry?

Jan 1, 1980

By T Blyth, D Holden, N Archibald, S Huffadi

The Morning Star mine is owned by Hill 50 Gold NL. Gold is hosted in quartz-carbonate ¦stibnite ¦molybdenite veins that occur in a series of deformed, altered and metamorphosed mafic volcanics with subordinate sediments and felsic intrusive rocks. The irregular gold distribution and its relationship to structure and alteration intensity makes the definition of stoping limits difficult. Understanding the structural evolution of the orebodies and the contemporaneous and later structures that affect the orebodies has been very useful in this context. This paper reports on a detailed mapping exercise (as part of a more extensive and on-going investigation) and the integration of this mapping with other geological and grade control data in a 3D modelling environment to provide an expanded basis for stope design. Three types of mineralised zones can be discriminated based on the morphology of the veins within. They are:those associated with strongly folded, thick veins (approximately 1 m thick eg 05 orebody); those comprising planar, boudinaged and some folded veins which consolidate to form tabular, steeply dipping bodies (eg 010 orebody); and zones containing the above vein types and thin, highly deformed veins within zones of intensely foliated country rock that result in localised, irregularly distributed high-grade gold zones (eg 02 orebody). The mineralised zones associated with thick folded veins are typically predictable over many tens of vertical metres. The second and third types of ore zone is generally less predictable. Detailed mapping and structural kinematic studies indicate all ore zone types are affected by progressive deformation involving strong strain partitioning. It is interpreted that high strain zones, recognisable by intense foliation development and highly deformed veins, are the latest stage of a progressive deformation which approximates bulk flattening. Structural controls on mineralisation can be defined at two different scales.Regional scale folding has deformed a sequence of mafic volcanics with interlayered sediments and felsic intrusives. Initial geometry of felsic bodies relative to orientation of the primary lithological layering and the bulk shortening direction is interpreted to be critical for initiation and development of strongly dilatant zones within this package of rocks, and Local scale dilation is evidenced by development of several vein sets whose range in orientations and opposed vergence relationships suggest a pre-folding origin comprising both extensional and hybrid shear-extensional types. Continued deformation resulted in folding of these veins with strong strain partitioning. Major vein packages are closely spatially associated with the felsic/mafic contact and an interpreted early structure which appears to have partitioned early dilation. This structure is now obscured by strong deformation but is currently represented by a zone of planar veins.

Jan 1, 2000

By D. Harrington

Research in connection with occupational diseases, including silicosis or, more definitely, pneumoconiosis, has been prosecuted much more actively in North American countries during the past 5 or 10 years than in any other known period. This applies particularly to the United States, owing largely to the fact that in recent years compensation for ill health presumed to be caused by industrial work of certain kinds is being paid to a far greater extent in this country than previously. Most other countries have had occupational-disease laws for many years. Court rulings in the United States, which started 5 or 6 years ago, have given a few heavy verdicts in connection with ill health or death caused, or alleged to have been caused, by some phase of occupational work other than traumatic injury, and these have called attention to the fact that ill health and even incapacitation can be caused by some kinds of employment. With the onset of the world-wide financial depression, which resulted in permanent abandonment of many business or industrial enterprises (among them mines) in the United States, the workers frequently believed that they could expect nothing in the future from their former employers, hence they felt free to demand monetary benefits or damages because of ill health which they suffered, or thought they suffered, because of their previous employment. The result was a flood of lawsuits and. compensation claims for occupational disease, particularly where dust was involved.

Jan 1, 1938

By A. J. Dudzik

In 2006 Arch Materials initiated the development of an underground limestone mining complex. The decision to proceed with the project was the end result of several years of market research and geological reconnaissance. The scope of the project included the construction of two declines to the mining horizons located approximately 900 feet below the surface, the means and methods of this phase will be the primary focus of this discussion. The design, fabrication and erection of a state of the art crushing and screening processing plant which when completed will have the primary crushing located on the mine level allowing uniformly sized material to be brought to the surface by means of a highly efficient conveyor system and a surface portion of the plant where material would be additionally processed, screened and stockpiled into specific product types. Also included in the scope of the project is the construction of offices, warehouse and shop facilities necessary to support the operations, commercial sales and distribution of the finished products.

Jan 1, 2010

By P J. McCarthy

Globalisation and consolidation is resulting in the mining industry coming to be dominated by a small number of very large companies seeking to lever assets and knowledge to create wealth. As an important service provider to the mining industry, the minerals tertiary education sector needs to understand these global drivers and respond to them. However, it is under-resourced and its sustainability is under challenge in all Western countries. Through the establishment and funding of the Minerals Tertiary Education Council (MTEC), the Minerals Council of Australia (MCA) has provided a unique opportunity to build a national, world-class minerals tertiary education environment in Australia that can be sustained in the long-term. This paper reviews how the global changes occurring in the mining industry provide the model for what needs to occur in the minerals education sector and how MTEC is the logical vehicle to facilitate these changes. It concludes by suggesting that the time has come to integrate the minerals tertiary education providers into one business. Furthermore, the vision should be for a global mining education academy based around a virtual university capable of servicing the cultural diversity and continuing education needs of the global minerals industry.

Jan 1, 2001

The Bureau of Mines studied available information on the nature and occurrence of potential sources of aluminum in the United States, its Pacific island possessions, and Puerto Rico to obtain data for use in evaluating the production capability and costs of extracting the aluminum from such materials. The quantity, type, and grade of the materials range from 4 billion tons of bauxite, bauxitic clay, and kaolin averaging 33 to 42 percent Al2O3 to nearly 600 billion tons of anorthosite containing only 27 percent Al2O3. Principal deposits of bauxite, bauxitic clay, and kaolin occur in Arkansas, Georgia, Hawaii, and Oregon. Major anorthosite deposits are located in New York, Wyoming, California, Idaho, and Montana. About 11 billion tons of material in deposits of various types of clay, the kyanite group of minerals, laterites, and shales averaging 27 to 30 percent Al2O3 comprise additional resource's from which aluminum some day may be extracted. Material meeting specifications of the study was found in only 22 States and the Pacific island possessions. Utilization of these large low-grade sources of aluminum awaits development of processes that are economically competitive with the Bayer process for extracting alumina from baxuite, which is at present the only commercial ore of aluminum. Changes in economic and political conditions also may play important roles in the eventual development of the potential sources of aluminum.

Jan 1, 1967

By Li Xi

This paper describes how a back-propagation neural network is built for predicting the properties of engineering materials from their other properties, compositions or processes. A predicted result of the impact toughness of a 12Cr-2Ni-1.5Mo stainless steel from its tempering temperature is presented. Furthermore, the combination of this neural network for prediction is able to supplement the unpredictability of the expert system outside its domain of expertise. An integrated system may perform more intelligently and solve more complex problems as well as human expert, in some case even better.

Jan 1, 1992

By K. V. K. Prasad

Forecasting mined grade variability from exploration information is a challenging task in mine planning. For effective planning of activities such as workplace scheduling, ore grade quality control etc. development of realistic numerical/simulation models of in-situ variability from exploration information is an essential first step. Geostatistical conditional simulation (GCS) is one of the well known methods to develop these simulations. Recently, stochastic fractal models based on the assumptions of scale-in variance and self-similarity have been used for developing simulations of several natural phenomena. It has been suggested that these models might permit generation of short-scale variability information from exploration data with greater fidelity when the data satisfies the attendant assumptions. In this paper the stochastic fractal models are reviewed and their relationship to geostatistical variogram models is examined. A comparison of the two simulation techniques has been per-formed using coal sulfur data from a mined out coal property. The results of this comparative analysis are also presented in the paper.

Jan 1, 1992

By P. F. Sands

This U.S. Bureau of Mines report reviews the state of the art in blind pneumatic stowing of backfill in voids in abandoned coal mines. It contains a short history of the development of pneumatic equipment in mining and four recent case histories of blind pneumatic stowing. Limitations of pneumatic stowing in terms of equipment wear, costs, backfill material, and methodology are discussed, and some new procedures and designs are reviewed. A bibliography covering pneumatics in mining is included also. This report provides background for the preparation of a Bureau test program in which the variables affecting the efficiency of pneumatic backfilling will be studied using a full-scale surface test facility.

Jan 1, 1990

Modem mineral exploration and development takes place within a data-rich context underpinned by a wide range of data acquisition, processing and interpretation technologies. This leads to requirements for consistent and explicit methods by which the relative risks - or success probabilities - of exploration programs can be assessed and communicated. Bayesian risk assessment methods are outlined which provide a starting point for this more rigorous approach to exploration investment.   Effective governance of information technologies becomes a core function of the modem competitive Board. As such it becomes a component of any business audit and any assessment of the quality and success potential of a company. Limited data however suggest that the average Board may be under-represented in this increasingly critical skill area.

Jan 1, 1997