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By G. Bonnell, W. Lidkea, M. C. Bétournay, E. Edwardson

"Hydrogen fuel cells are a known technology, having been applied to stationary (e.g equipment, buildings, and power plants) and vehicle applications (e.g transit buses and space shuttles). There is currently a growing need to provide alternate power systems to diesel fuel for underground mining vehicles to improve underground air quality and reduce production costs and greenhouse gas emissions.To date, however, fuel cells have not been exposed to underground mine air and physical conditions. A testing program was carried out to provide information on the vulnerabilities of fuel cells as part of a number of proof-of-concept projects to apply hydrogen power to underground mining vehicles. The fuel cell type of choice for the industry, the proton exchange membrane, would function at the range of temperatures encountered in underground and surface operations, and use hydrogen that is stored under low pressure and risk.A small fuel cell stack was tested in a cooperative project between CANMET, the Fuelcell Propulsion Institute, Inco, the Ontario Ministry of Labour, Sandia National laboratories, and H-Power. This article will review the tests carried out to measure the effects from high humidity, mineral dust, diesel emission gasses and diesel particulate matter, as well as from shock and vibration provided to the unit in underground conditions at Inco’s 175 Orebody minesite and Stobie mine. The test results provided will show that the unit was not affected by the underground conditions; physically and electrically, the unit performed without any reduction in operation or adverse effects imposed."

Jan 1, 2005

This paper presents a resume of the likely profitable mining areas in New Zealand. It covers the main 'minerals' û gold, coal, oil and gas, ironsands, silica sands, clays, lump silica, perlite, sulphur and limestone. The potential mining projects are depicted on a map of New Zealand together with the associated works involved in hydro-electric and geothermal power development requirement for industries such as aluminium, nickel ferro-silicon or silicon carbide production. The political need for mining development to relieve unemployment and reverse emigration is stressed. A case is made for exploration and development assistance by government in labour re-training, energy supply and transportation, if the tremendous losses through lack of use of human and industrial resources are to be rapidly reduced. These losses are currently estimated at $10 000 000 000 per year. The need for protection of the sanctity of contract and security of tenure of all mining operations is touched on briefly as is the need for a reasonably balanced view on conservation. However, as both of these are more properly covered in papers on the legal and environmental aspects of the mining climate, they are presented here only as they affect the economy of the mining operation. Finally, there is a brief comment on the mining climate in New Zealand relative to Australia and South Pacific mining operations.

Jan 1, 1990

By P. A. Davies

Paper presented at the conference: Risk assessment in the extractive industries, held in Exeter, UK, 23-24 March 1994, and first published London: IMM, 1994, preprint volume, 11pp., 15 refs. Hazards such as vibration, dust emission and fragment projection can result in an area called the Danger Zone being set around a blasting site. Traditionally Danger Zones have been set solely on the basis of consequences (e.g. based on the maximum distance of rock projection or expected ground vibration plus a defined safety margin). Advances in risk assessment and its growing acceptance as a safety management tool have led to the setting of Danger Zones based on both consequences and frequency of occurrence. This allows distances to be optimised on the basis of acceptable risk levels rather than the potential consequences of infrequent events. The setting of a flyrock Danger Zone is used to demonstrate a risk-based approach compared with a traditional consequence approach

Aug 1, 1995

Pressure drops were measured in a column packed with glass spheres and wax particles, both in random and preferential distributions. Variables investigated included wax content, gas flow rates, and temperatures.It is shown that for random distribution of wax, pressure drop is exponentially related to wax content above the melting point of wax and that below this it increases with increasing gas rate and temperature.For preferred distribution of wax the highest increase in pressure drop is obtained with horizontal distribution of wax and the least with vertical distribution.Comparison with operating blast furnace data and application of results to practice are also included.

Jan 1, 1970

By Benoît Demers

Dans ses opérations de traitement de concentré de zinc, l?usine de Zinc Électrolytique du Canada à Valleyfield génère un résidu minier appelé « jarosite ». Jusqu?en 1998, le jarosite était transporté hydrauliquement dans des bassins construits en argile. Le jarosite sédimenté possède une consistance très molle (impossible de circuler à pied sur le résidu consolidé) avec une eau interstitielle acide contenant des teneurs élevées en métaux. Ces caractéristiques particulières au jarosite rendaient très coûteuses la construction et la fermeture des bassins de résidus. En 1998, Zinc Électrolytique du Canada a implanté un nouveau procédé, développé chez Noranda, dont le principal objectif était de stabiliser chimiquement et physiquement le jarosite. Un nouveau concept de déposition a été élaboré pour le nouveau résidu minier appelé « jarofix ». Les grandes caractéristiques du nouveau procédé et du concept de déposition sont : ? Le jarosite est lavé et déshydraté à l?usine avec un système de filtre; ? De la chaux, du ciment et de l?eau sont ajoutés pour former le jarofix; ? Le jarofix est transporté par camions jusqu?à l?aire d?accumulation; ? À l?aire d?accumulation, le résidu est géré selon un concept d?empilement. L?élaboration du concept d?empilement et de l?aire d?accumulation devait tenir compte des caractéristiques de déposition du jarofix, de sa résistance à l?érosion hydrique et éolienne, de la gestion de l?eau de ruissellement, de la faisabilité de construire les digues de ceinture en utilisant du jarofix durci et de la nécessité de restaurer progressivement l?aire d?accumulation. Le déchargement du jarofix se fait à partir d?une rampe qui progresse avec une pente ascendante pour développer un front de déversement de plus en plus haut. La hauteur du tas de jarofix atteindra 30 m au centre du site. L?aménagement initial de 1998 a inclut une digue d?amorce de 3 m de hauteur, une rampe de déversement de 8 m de hauteur et un bassin pour la gestion de l?eau de ruissellement. Les propriétés du jarofix consolidé dans l?aire d?accumulation sont déterminées annuellement. Le jarofix durci possède la consistance et la résistance d?une argile très raide. Sa conductivité hydraulique est similaire à celle d?un silt et il résiste bien à l?érosion éolienne. Après trois années de déposition, la température du jarofix au milieu du dépôt demeure élevée. Le jarofix durci est facile à excaver et à compacter, ce qui en fait un excellent matériau pour la construction des digues de ceinture en périphérie du site.

Nov 1, 2002

By F. -Z. Ji, A. G. Irons, M. Barati, K. Coley

In order to optimize carbon injection into oxidizing slags, in terms of carbon and iron yield, we must have a detailed understanding of the kinetics of the reactions involved. The current study measures the rate of carbon oxidation during injection at steelmaking temperature by means of injections of coal into EAF slags. The compositions of analysed outgoing gas were used to calculate gas flow rate and hence the gasification rate of carbon. A fundamental equation to predict residual carbon in slags was developed. The predictions using this model at moderate injection rates are in good agreement with experimental data. The reaction rate of EAF slag with carbon is under mixed control by the slag gas and the gas carbon reactions. The relative importance of each step depends mainly on the v-ratio of slags. A relative reactivity parameter ? has been defined and it is found to be important to carbon-slag reaction kinetics and slag foaming. Key words: carbon-slag reaction, kinetics, slag foaming.

Jan 1, 2004

Overview ?G-9 Discovery Hole 420 drilled May 2005 ?14.16% Zn, 1.76% Cu ?Greenfield discovery built into the G-9 Mine in under 4 years. ?Utilized a unique ?Parallel Track? approach to fast-track mine development. ?Raised over $200million in financing without a Feasibility Study. ?Mine built for $149.7 million, only 20% over PEA. ?Commercial Production declared April 1, 2009. ?G-9 Mine has now completed the first year of commercial production on April 1, 2010. ?Initial cash costs per pound of zinc US$0.39/lb -US$0.45/lb range. ?Mill operating at over1,900 tpd in March 2010, well above design capacity (1,500tpd) only one year after starting commercial production. ?Balance Sheet -$167 million assets, $24 million long-term debt, $22 million cash. ?Restarted Exploration ?excellent initial results. ?Strategically positioning Farallon to grow to a mid-tier mining company.

May 1, 2010

By Steve Skelhorn

Edmonton South LRT is the latest expansion of the Subway system in Edmonton, Alberta, Canada: Consisting of twin 5.8m segmental lined tunnels, 280m long, driven by a Lovat EPB machine. The key challenges were as follows. A 6% downhill grade. Tight radius curves of 250m.Overlying structures within 3m of the tunnel. Strata consisting of sand above the water table, glacial tills and bed rock below the water table. Located within The University of Alberta Campus and adjacent to a hospital. Northern Alberta climate with winter temperatures routinely falling below—minus 30 degrees Celsius. This paper provides a case history and outlines the challenges involved in completing this project.

Jan 1, 2005

By G. D. Bakulev

Economic Importance of Gasification of Fuel and Brief Outline of Development of Underground Gasification of Coal in the U.S.S.R. The underground gasification of fuel offers a number of economic and social advantages, principally the following: 1. Full automation of labor-consuming coal-mining processes, which resist complex mechanization and automation, particularly shaft mining. 2. Elimination of hard, dangerous, and often unhealthful mining work. 3. Creation of hygienic conditions for personnel employed in gas production, as well as for those in boiler rooms using the gas. 4. Possibility of automation of complex production processes of thermal-electric powerplants using underground gas with economic installations for steam production. 5. Economic operation of thermal-electric powerplants constructed in the areas of underground-gas production. 6. Release of railroads from the burden of transporting fuel. 7. Extension of the power base of some areas in need of fuel and of the economy as a whole due to use of fuel deposits not amenable to normal mining practices. 8. Reduction of capital investments per unit of energy produced in the form of fuel. 9. Substantial increase in general labor productivity. 10. Possibility of substantial reduction in the cost of fuel produced and of electric power produced from underground gas.

Jan 1, 1962

By Chris Uys, Johan Labuschagne

Sishen Iron Ore Mine, located in the Northern Cape, is an open cast mine excavating approximately 100 million tons rock to produce 25 million tons of high grade haematite ore per annum. The size of the pit is approximately 12 km ‘1.5 km ‘150 metres. The final depth is planned to be around 350 metres. It is hard rock mining operation employing the conventional truck and shovel method. Mining benches are twelve and a half metres in height and are divided into blasting blocks, each consisting of approximately 300 000 tons of material.

Jan 1, 1997

The Mineralogy and Reactivity of Pyrrhotite from Selected Nickel Ore Deposits and its Effect on Flotation Performance

Sep 13, 2010

By Fathi Habashi

"Crushing and grinding of ores and their beneficiation by washing away gangue minerals has been practiced since ancient times. Primitive crushing was done by hand pounding the ore with a hard stone then by using metallic hammers. The mortar and pestle was mechanized using a lever and when the size of operations increased in the middle ages, the stamp mill was introduced. The grindstone played an important role in grinding of ores. Panning for gold and hand sorting of minerals were two old methods of separation, now gave way to modern techniques. Flotation started in the middle of the nineteenth century by using oils to collect the mineral particles and float them on the surface of the aqueous slurry. It was only in the 1920s when it was discovered that organic compounds were affective floating agents. Textbooks written by distinguished engineers such as Rittinger, Rickard, Pryor, Taggart, Richards, Gaudin, and others contributed to the recognition of this field as a new discipline to be taught in Universities. INTRODUCTIONThe ancient Egyptians knew already that it would be easier to melt an earth rich in gold particles than another which is poor. As a result all efforts were made to enrich the gold by washing away the light gangue minerals (Figure 1). Another ancient method for enriching gold particles from a river stream was by means of fleece, hence the Greek myth of the “golden fleece”. The present day Georgia was known in ancient times as Colchis and was a center for gold working. It was known to the ancient Greek as the land of Golden Fleece. The use of special cloth to catch gold particles was also described by Agricola in his 1555 book De Re Metallica (Figure 2)."

Jan 1, 2009

By D. McCarthy

Contract is a PC-based software program designed to satisfy the main features that have been identified to be lacking from cost estimation systems currently in place in the Australian coal industry. Contract was developed in conjunction with an Australian contracting company to refine the existing core structure used by the company for project evaluation. The key feature of Contract is the availability of analysis functions to explore multiple options within a contract project by altering identified variables. The ability to update project files has been incorporated into Contract to ensure that it is user-friendly and relatively simple to use. Lists of mining equipment and consumables are stored in MS ACCESS database files, along with the supplier details for each item. Each time a project is initiated there is a dynamic link to the database files and the most recent current information is retrieved and linked with the project. Contract provides an option to calculate the changes in metre unit cost as a function of the average development cost. Keywords: Contracting, cost estimation, sensitivity analysis.

Jan 1, 2003

By G. G. Morgis

In carrying out the provisions as set forth by an Act of Congress (36 Stat. 369) approved May 16, 1910, effective July 1, 1910, and the amended Act of February 25, 1913, (37 Stat. 681), the Bureau of Mines, among other activities, conducts inquiries and scientific and technologic investigations concerning mining with a view to improving health conditions and increasing safety and disseminates the general information gained by these studies. Through the medium of these publications, the causes as well as the methods that have been found most satisfactory in combating undesirable conditions are brought to the attention of the mining industry. This bulletin describes health and safety reports that have been published for the period July 1, 1955, through June 30, 1961. Technical Paper 705 issued in 1948 contains a listing of all Bureau of Mines publications dealing with health and safety in the mineral and allied industries from 1910 through 1946; Bulletin 558 contains a bibliography of such reports that were issued from January 1947 through June 1955.

Jan 1, 1962

By R. Zunich, E. Rybinski, M. Grondin, B. Flintoff

It is uncommon these days to read a business magazine or newspaper without finding a reference to Knowledge Management (KM), and its critical importance to corporate success. One definition of KM is: “getting the right knowledge to the right people at the right time and helping them to put information into action in such ways that strive to improve organizational performance.” In the minerals processing industry we could assert that we have been practicing this for years through effective operator training. In most cases we would probably be wrong. Training has certainly filled the need of addressing safety and basic operational issues, but we must collectively focus on education (learning), and the difference, as measured in outcomes, is not at all subtle. This paper briefly examines the history of training and education in the mining industry, and looks in more detail at the impact of one company’s approach to empower its workforce, while keeping the ultimate goal clearly in mind: “The great end of knowledge is not knowledge, but action.” (T.H. Huxley)

Jan 1, 2001

By Kerry Spickelmier

Editor's note: information for this feature was taken from the published APCOM proceedings. Computer trends, with special focus on the reasons for computer use, grabbed the lion's share of attention at the 23rd worldwide meeting on the Application of Computers and Operations Research in the Mineral Industry (APCOM 23). However, technical topics did not provide the meeting's sole focus. The last-minute inability of certain former communist countries to fund the travels of a few scheduled speakers was a reminder that science does not operate in a void. As with all technical progress, the APCOM presentations raised interesting questions regarding interrelated organizational dynamics and political and socioeconomic issues. Consider US Bureau of Mines (USBM) research to design an expert control systems to "duplicate" an experienced, "good" operator during automated underground roof bolting. In his presentation of the project, Takach, Jr. stressed the importance of preserving the ability to switch from automatic to manual drilling control. From a technical standpoint, this allows the expert system to "learn" from a good operator. As important, he said, is that this flexibility decreases the human operator's sense of being replaced by the machine. The question arises: Which will loom larger in union minds, increased operator safety through remote opera¬tion or the potential for total operator replacement? Like any new product, computer technology relies on marketing to aid its acceptance and use. Consider, too, a decision support system, by Schena and Gochin, for mineral resource management in a developing country. The authors said "the analysis permits the assessment of the overall socioeconomic consequences of mineral prospects and allows incorpo-

Jan 1, 1992

By Oliver Bowles

Sandstone, a widely distributed siliceous sedimentary rock, is the third most popular building stone in the United States. It is formed by the breaking down of preexisting rocks by weathering, subsequent segregation of the detrital quartz grains into discrete deposits by the sorting action of water or wind, and finally cementation of the quartz sand into a coherent rock. The homogeneity and resistance to weathering of the resultant sandstone make it suitable for exterior construction. Its excellent wearing properties explain its popularity for flagging and stair treads. However, quarrying and dressing methods and costs are adversely affected by the abrasiveness and hardness of sandstone especially as compared to limestone.

Jan 1, 1963

By K. Rainer Massarsch

In some parts of the world, vibrators are used extensively for different types of foundation engineering projects. If used correctly and in suitable soils then vibratory pile driving for example is very efficient. However, soil conditions and the installation procedure have great significance for the driving resistance and affect the bearing capacity of vibrated piles. Also the intensity of ground vibrations which are transmitted to the surrounding soil is affected by the vibration process. In spite of the increasing use of vibrators and the rapid development of vibrator technology, many aspects of pile-soil interaction are not yet understood. In order to asses the importance of factors, which govern pile installation (and extraction), it is necessary to consider the entire chain of vibration energy transmission from the vibration source to the pile, the interaction between the vibrating pile and the soil and the wave propagation in the subsoil, Fig. 1. [ ] Fig. 1. Transfer of vibration energy from the vibrator through the pile into the ground In the present paper, some important aspects of vibratory driving and their significance for pile installation and soil compaction will be discussed.

Jan 1, 1995

By Steve Kral

In the United States, the U.S. Environmental Protection Agency (EPA) is set to implement its Tier 2 air quality standards governing high-horsepower, off-road diesel engines. The regulations take effect in January2006. In Europe, similar standards, called Stages, are due to take effect about the same time. And other markets, such as Japan and Australia, have their own standards on tap. Tier 2 standards will further reduce the amount of nitrogen oxide (NOX), sulfur dioxide (SO2), diesel particulate matter (DPM), carbon monoxide (CO) and hydrocarbons off-highway diesel engines are allowed to emit. And even more restrictive Tier 4 standards are due in 2011. The upshot is that operators of high-horsepower engines, particularly in mining, will begin using in their new off-road haul trucks, excavators, shovels and other mining machines diesel engines that are designed to meet these more stringent standards.

Jan 1, 2004

Electricity supply constraints in SA are increasingly challenging mines to operate more energy efficiently without reducing production output. Mining compressed air systems are well known to be operated inefficiently and are also a major power consumer. Two available and proven technologies can be applied on new and existing mines to replace or and optimise available compressed air facilities and achieve meaningful reductions in electrical power consumption; ? Hydro powered drilling and mining is significantly more energy efficient than compressed air and provides drilling rates that are twice as fast. ? Stope drilling systems using compressed-air or water drills allow further energy savings. The technologies are discussed and a broad strategy to selectively apply these them together is presented.

Jan 1, 2008