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By L. Bloomquist, C. Arnoldi

"This paper describes how Automated Mining Systems (AMS) is evolving the state-of the- art in guidance systems for autonomous underground vehicles. The techniques, tradeoffs, and lessons learned from these systems are described, including the safety regime that has been implemented.First generation autonomous guidance systems for underground vehicles relied on infrastructure for the vehicle to follow. However, there are additional costs associated with that approach.The current generation uses a pair of laser range finders as its only guidance sensors. This system uses a minimum of infrastructure, in the form of a redundant system of location referencing. Advanced steering and drive control algorithms are incorporated into this generation of system.The next generation of infrastructureless guidance systems will be based on a 3D vision sensor, which was originally developed for autonomous Mars rovers and is being adapted for underground mining use. Results of early underground field trials are presented, along with a description of this emerging technology."

Jan 1, 2004

By R. Anthony Hodge

1. Today?s Reality: Voisey?s Bay EIA Activities of the Canadian Environmental Assessment Agency The Tulsequah Chief Decisions The Bank of Montreal The World Bank World Business Council on Sustainable Development The Government of Canada Many company policies

May 1, 2002

By Joël Kapusta

La pyrométallurgie du cuivre est essentiellement une chaîne de trois étapes successives d’oxydation préférentielle du fer et du soufre et des impuretés moins nobles que le cuivre qui sont contenues dans le concentré de cuivre issu de l’usine de concentration du minerai, aussi appelée concentrateur. La Figure 1 illustre la chaîne complète d’élaboration du cuivre depuis la mine jusqu’au cuivre pur. La voie hydrométallurgique traite le concentré par lixiviation, c.à.d. par dissolution en phase aqueuse à température typiquement inférieure à 100 ou 150⁰C, alors que la voie pyrométallurgique traite le concentré par fusion à température de l’ordre de 1200 à 1300⁰C.

May 2, 2024

By P. K. Naik, B. Das

Flotation studies were carried out to recover carbon values from blast furnace flue dust containing ~30.34% carbon, 4.6% volatile matter (VM), and 65.03% ash. The variables chosen for the experiments were dispersant (sodium hexametaphosphate), pH, collector (diesel oil), and frother (MIBC). The experiments were designed according to a 24 full factorial design method and regression equations for the recovery of carbon and product grade were determined from the data. Experiments were performed to optimize recovery and grade using the steepest ascent method. The maximum recovery of carbon was 90.0% with a concentration of 56.5%, whereas the maximum obtainable grade of carbon was 66.35% with 50.45% recovery.

Jan 1, 2005

By J. A. Jr. Carpenter

Expanding world economic prosperity, probable peaking of conventional petroleum production in the coming decades and environmental concerns require efforts to increase the efficiency of, and the development of alternatives to, petroleum-based fuels used in automotive transportation. In January 2002, the U.S. Department of Energy (USDOE) and the U.S. Council for Automotive Research (USCAR) of the "Big Three" traditionally-USA-based automakers, DaimlerChrysler, Ford and General Motors, formed the Freedom Cooperative Automotive Research (FreedomCAR) Partnership to fund high-risk, high-payoff research into advanced automotive technologies with the potential for eventually lowering the USA's nearly complete (95%) dependence on petroleum, 55% imported, for its transportation fuels. FreedomCAR replaced the Partnership for a New Generation of Vehicles (PNGV) which existed from 1993 to 2001. In January 2003, the energy-supply industry joined with the FreedomCAR Partnership forming the FreedomCAR and Fuel Initiative (FC&FI) to develop the technologies needed for the mass production of fuel-cell vehicles using hydrogen as fuel and the infrastructure needed to deliver the hydrogen to the consumer. The goal is to enable the automotive and energy-supply industries to make commercialization decisions in 2015 on large-scale introduction of such vehicles and on developing the infrastructure beginning in 2020. In addition to work on fuel cells and hydrogen infrastructure, the FC&FI conducts research on technologies with the potential for nearer-term energy efficiency and environmental benefits, such as new engine concepts, lightweight materials, and engine-electric hybrid propulsion systems. Lightweighting is seen as crucial for shorter and for longer term benefits because hybrid and fuel-cell powertrains are expected, at least in the early stages of adoption, to be heavier and more costly per unit of power than the standard internal-combustion, gasoline- or diesel-fueled powertrains they replace. Research and development (R&D) on casting of aluminum automotive components were major parts of the PNGV and R&D on casting of magnesium automotive components have been and are so under FreedomCAR. This presentation will review those efforts.

Jan 1, 2006

By John G. Henning

Unplanned ore dilution has a direct and large influence on the cost of a stope, and ultimately on the profitability of a mining operation. This paper presents results of a study on the influence of a variety of factors on ore dilution in a blasthole stoping environment. A series of 3-D numerical models were developed and analyzed to examine the effect of mining depth, stope geometry and stope setting within the orezone extraction sequence. To quantify modelled ore dilution from the three-dimensional simulations, the ore Dilution Density (DD) is a term introduced in this study to denote potential hanging-wall overbreak. It was found that hanging-wall overbreak is not significantly influenced by depth alone, and that stopes with large or small axial ratios are more stable than large rectangular stopes. It was also demonstrated that, in addition to stope dimension, the amount of unplanned dilution differed according to stope type. Five stope types were identified, based on their position within a tabular blasthole mining sequence. The methodology presented in this paper can be adopted to develop mine-specific design tools for the estimation of ore dilution associated with a proposed mine design. This can prove extremely helpful in the process of underground mine planning and optimization.

May 1, 2007

By S. Bergquist

In this paper, it is investigated how different types of automation would affect the safety for workers in asphalt paving. The risk for the workers on road construction sites is consistently high in comparison to the average risk of the working population. Automation has been suggested as an alternative for improving the safety in roadside construction assuming that removing workers will inherently eliminate the risk of them being injured. In this paper, the potential for improving the safety using automation is analyzed in detail. By investigating accident statistics and understanding the type of accidents that appear, several different automated functions for increased safety are proposed and described. Based on available statistics, it is possible to estimate the safety benefit, as the reduction in fatalities, for several of the proposed functions. The highest safety benefit would be achieved by automating the road traffic driving through the work zones. This has the potential of reducing the total number of road worker fatalities with over 30 %. In addition, it would decrease the number of road traffic accidents in work zones. Automation of construction machinery and dump-trucks also has the potential to increase the safety.

Aug 1, 2013

By Ben R. Bjorkman

The future is here ? or at least that?s what Mine Planners predicted some 15 years ago ? that by 2004 we would have man-less mines running themselves using space-aged technology. Truthfully, though, there hasn?t been much change in mining methods in the past decade, but thankfully that?s all about to change. The benefits of autonomous ? even Tele-operated mining (especially in narrow-vein ore bodies) are wellknown: increased production hours by eliminating travel time to and from the face, continuous production at the face while crews screen and bolt behind the working equipment, less liability for workers? safety in certain areas, etc. But when plans are put in place to accomplish this vision, things stagnate and production carries on as before. This paper examines the components necessary to make that vision a reality. First we?ll detail the technology required to enable Tele-operation ? even autonomous operation of mining machinery, then we?ll look at what?s wrong with the current way we?re mining, and finally conclude with a critique of the machinery itself.

Oct 1, 2004

By K. Izumi

Ultra-grain refinement and high strengthening of metals by accumulative roll bonding (ARB) was widely reported. However, applications of ARB to magnesium alloys were rather limited. In this study, Mg-9%Li-1%Y sheets were applied to ARB at room temperature. Six 0.5 mm thick sheets were stacked and reduced into 0.5 mm thick by four passes. The procedure was repeated up to three cycles, so that the equivalent strain of 6.2 was applied. The sheets show dual phase structure with a (hcp) and ß (bcc). Grains elongates to the rolling direction with increasing number of ARB cycles. After three cycles, fragmented a grains with average size of about 300 nm are uniformly distributed. After the first cycle, the ultimate tensile strength increases to 180 MPa from 133 MPa, while the elongation decreases, however, still high (26%). The tensile strength slightly decreases by the second cycle and does not change at the third cycle. Meanwhile the elongation increases by the second cycle and the sheets show 41% of the elongation after the third cycle.

Jan 1, 2006

By Roger J. Higgins

Papua New Guinea is a country on the cusp of development, struggling to find a balance between the demands of national and regional growth, landowner expectations and the maintenance of cultural identity. Ok Tedi Mining Limited is the single largest contributor to PNG?s economy, representing about 10 percent of the country?s GDP. OTML is demonstrating that business and country risk can be managed through effective, respectful partnerships with local communities. OTML?s relationships with the communities of PNG?s Western Province are multifaceted. Communities have borne the brunt of the mine?s environmental impact, yet have benefited enormously from the development that the mine has brought. Importantly, the PNG economy is now the ultimate beneficiary of more than four-fifths of the dividends from the mine, the majority of which are held in trust for long-term sustainable development projects. The paper describes how OTML works with the Western Province communities to create a secure operating environment that recognizes the people?s aspirations for development and self-determination.

May 1, 2002

By M. Rantapaa

Measurable improvements in throughput have been documented at Barrick Goldstrike due to increased ore fragmentation through efficient drilling and blasting techniques. A decrease in throughput at the autoclave, due to increasingly hard ore, was identified in early 2002. A team of individuals from the open pit and process areas worked closely on the Drill-to-Mill (D2M) Continuous Improvement initiative to ensure that it would address the needs of both groups, with the target of actually improving throughput in future years, despite the projected harder ores. A series of tests were conducted to determine if adjustments to drilling and blasting could positively influence throughput. Better fragmentation and a subsequent increase in mill throughput were achieved through the use of electronic caps for more precision and flexibility, as well as for allowing extremely fast shots; explosives with a higher velocity of detonation (VOD) to provide for improved shock energy; and improved distribution of the explosives by decreasing pattern spacing. Early tests indicated a significant increase in throughput when processing identified harder ore. It is anticipated that the total process throughput (hard and soft ore) will increase by 6 tph in 2003 due to the improved fragmentation of the hard ore. Barrick Goldstrike?s D2M initiative includes roaster hard ore (BWI>17), as well as autoclave hard ore (BWI>15). Approximately 6 million tons of D2M material were shot in 2003, a relatively small amount compared to the 150 million tons to be mined. The benefit of additional ounces produced should far outweigh the additional drilling and blasting costs.

Jan 1, 2005

By R. Mckinstry, M. Rantapaa, T. Bolles

"Measurable improvements in throughput have been documented at Barrick Goldstrike due to increased ore fragmentation through efficient drilling and blasting techniques. A decrease in throughput at the autoclave, due to increasingly hard ore, was identified in early 2002. A team of individuals from the open pit and process areas worked closely on the Drill-to-Mill (D2M) Continuous Improvement initiative to ensure that it would address the needs of both groups, with the target of actually improving throughput in future years, despite the projected harder ores. A series of tests were conducted to determine if adjustments to drilling and blasting could positively influence throughput.Better fragmentation and a subsequent increase in mill throughput were achieved through the use of electronic caps for more precision and flexibility, as well as for allowing extremely fast shots; explosives with a higher velocity of detonation (VOD) to provide for improved shock energy; and improved distribution of the explosives by decreasing pattern spacing. Early tests indicated a significant increase in throughput when processing identified harder ore. It is anticipated that the total process throughput (hard and soft ore) will increase by 6 tph in 2003 due to the improved fragmentation of the hard ore.Barrick Goldstrike’s D2M initiative includes roaster hard ore (BWI>17), as well as autoclave hard ore (BWI>15). Approximately 6 million tons of D2M material were shot in 2003, a relatively small amount compared to the 150 million tons to be mined. The benefit of additional ounces produced should far outweigh the additional drilling and blasting costs."

Jan 1, 2005

By G. Whittle, R. Peevers, P. Moryoussef

Enterprise optimization is a relatively new optimization approach to mine planning used to jointly consider all aspects of a mining operation affecting the mine planning process and related valuation. In this paper, it is applied at SEMAFO's Mana operations in Burkina Faso, consisting of several open pits and a proposed underground mine. The surface-minable ore is relatively shallow, and the pits are long and linear. The underground operations, as currently envisioned, will consist of a stoping operation accessed by two ramps from the surface. Power is a concern at this property due to local power being produced largely by diesel generators, and it has become one of the key optimization constraints. Other important parameters are the mining and processing rates, underground configuration and cutover elevation. Enterprise optimization was found to improve net present value for the Mana Operations property by simultaneously optimizing multiple parameters and constraints to arrive at an optimal pit and mining phase design, optimal cut-off grades over time, and optimal ore feed based on ore hardness, power constraints, and head wades. Reserves were expanded several times over the course of the study to improve the valuation of the mining operation and put SEMAFO in its present enviable position of ongoing reserve increases.

Jan 1, 2011

By The Staff

THE object of the work was to increase the capacity of the plant and, if possible, to reduce costs of the actual unit grinding while doing so. The accompanying assays of an infra-sizer analysis of the cyanide tail (Table l) illustrate the problem in hand. The cyanide tail is a combination of two products, gangue and FeS2. The assay alters by virtue of a change in gold value due to grinding and the relative quantity of FeS2 in the sizes, which itself varies with the grind. The disposal tail is the residue after the cyanide tail is scavenged by flotation, most of the pyrite being removed for roasting. It presents a somewhat different problem, since grinding gangue is all gain, but -10 micron FeS2 does not float nearly as well as + 10 product. This results in compromise in the final size to be aimed at. Extra grinding has hardly any appreciable effect on the gold extraction from the FeS2. (See Milling Investigations Into the Ore as Occurring at the Lake Shore Mine; Trans. C.l.M.M., Vol. XXXIX, 1936).

Jan 1, 1940

By Anton Gronningsater

AS we know, Sir Henry Bessemer introduced Bessemer converting in the steel industry about 1855. It was not until twenty years later that the principles were adopted by non-ferrous metallurgists. In 1880, Manés first produced blister copper from matte in a converter, a very important forward step in copper metallurgy. For thirty years, up to about 1910, bessemerizing of copper matte was carried out in the acid-lined converter. It is not necessary here to enumerate all the shortcomings of that operation, one of which was that it strictly limited the grade of matte that could be treated; a 35 per cent matte was low in those days. From the early days of copper converting, many and repeated attempts were made to use a basic converter lining, and the older metallurgists will remember the numerous reports and discussions in connection with such experiments. These make interesting reading. I quote from a book published in 1900: ?'The siliceous lining is as much a part of the process of copper converting as magnesia lining is in the basic bessemer treatment of phosphoric iron, and it is suicidal to attempt any other kind of lining, either water-jacketed or basic.' "Even if the silica could be introduced in this way (through the tuyeres), it would still produce another trouble in the converter. The small particles of silica, being cold, would combine very imperfectly with the iron oxide and produce granulated and pasty slags, which could not be skimmed or poured out of the vessel".

Jan 1, 1942

By Patrick Moore

In 1971 the government of British Columbia issued a permit for the Island Copper Mine to commence disposal of 33,000 tons per day of mine tailings into Rupert Inlet, a marine fjord on the northwest coast of Vancouver Island. There was considerable controversy surrounding the development, public hearings were held, and as a requirement of the permit the company was obliged to carry out a comprehensive environmental monitoring program. The results of this program provide a thorough assessment of the environmental impact of submarine tailings disposal over the 24-year life of the mine. Following closure in December, 1995, the monitoring program continued for three years to determine the extent of marine ecosystem recovery and re-colonization. It is apparent from the findings of the monitoring program that the mine tailings were dispersed more widely than was originally predicted. It is also clear that widespread heavy metal contamination has not materialized. In retrospect it appears that submarine tailings disposal has resulted in far less severe environmental impacts than if the alternative of land disposal had been adopted. This review highlights significant aspects of public policy decision-making, design of environmental monitoring programs, and questions of interpretation of monitoring program data.

May 1, 2002

A case study for the application of a novel geostatistical technique for resource estimation of a narrow steeply dipping, gold-silver mineralized quartz vein deposit is presented. The technique is novel in two respects. First, mineral grades are kriged directly rather via the accumulation method more often applied to vein deposits and, second, a modified 2D ordinary kriging algorithm is used that allows the calculation of a single grade and variance for irregular shaped blocks of varying sizes. The objective of this investigation was to evaluate the suitability of this novel geostatistical technique for resource estimation of the Poura mine deposit and, if appropriate, to lay a firm foundation for future geostatistical work at the mine. The reserve estimation concentrated on the remnant ore blocks and pillars in both underground and surface workings. The data, which was collected in 2D coordinates with grade and vein thickness values, was first analyzed statistically and used to compute experimental semi-variograms. Appropriate semi- variogram models were fitted and various aspects of the estimation technique were evaluated using cross-validation error analysis, with acceptable results. A block kriging computer program called Krige2D was developed to implement the modified 2D kriging algorithm and calculations. Production data were not available to evaluate the computed block resources, but they were compared with a previous resource data determined using an arithmetic approach. The geostatistical technique estimated slightly higher grades but lower overall tonnages as compared to the earlier arithmetic estimates.

Feb 1, 2004

By S. Caron, P. Radziszewski

Industrial practice in mineral processing shows that an important problem in understanding and monitoring in-mill parameters is due to the lack of fundamental knowledge and appropriate sensors. However, over the last decade, Discrete Element Method (DEM) modelling has shown an interesting potential in describing the fundamentals of grinding mill behaviour, in improving the understanding of internal grinding mill dynamics, and in developing solutions to industrial practice. With the objective of bringing this modelling technology into the concentrator control room to assist operators, this paper aims to describe the main elements needed to apply this emerging and developing technology to on-line mill performance monitoring.

Jan 1, 2004

"This generic study has been developed in response to the frequently asked question, ""That is the best treatment route for refractory gold ore?"". The study has developed operating and capital costs for many potential treatment routes and they are presented here in a generic form. All costs are in relation to the value of 1.00 given to the base case, a 1000 mtpd bio-oxidation plant, operating at 25% solids and 72 hours residence time.There is unfortunately no simple answer to the above quest ions. The treatment of refractory ores is a complex subject, with many variables, such as mineralogy, chemistry, environment and tonnage. However this study does offer information and relative numbers that we believe will be of assistance to gold metallurgists in obtaining a ""first shot"" at estimating costs.Equally, this technology is a rapidly evolving one. As more plants are commissioned, and test programs completed, better data is constantly being generated. For a generic study of this type to remain useful it will need regular updating and adjustment."

Jan 1, 1989

By M. J. Michaud, M. J. Lavigne

"A cornerstone of any successful mining project is an understanding of the mineral assemblage and metal distribution comprising the deposit. Knowledge of the precise mineral/ metal zoning enables an operation to utilize different mining and processing methods optimized for different parts of the deposit. The Lac des Iles mine, located in northwestern Ontario, is one operation that depends on a good understanding of these issues. Current resources for the Roby Zone total 94.1 Mt grading 1.66 g/t Pd, 0.18 g/t Pt, 0.14 g/t Au, 0.062% Cu, and 0.053% Ni.The Roby Zone occurs within the gabbroic portion of the Lac des Iles intrusive complex and consists of three compositionally and texturally different ore types with variable PGE, base and precious metal contents. PGE occur as sulphides and bismuthotellurides in net-textured sulphides, coarse sulphide blebs and as finegrained inclusions within secondary silicates.Knowledge of the precise mineral/metal zoning has directly and indirectly improved several operational aspects, including resource modelling, mining, and processing. For example, metallurgical recoveries have been increased by up to 3% to 5% and concentrate grades have increased by up to 100%. IntroductionLac des Iles Mines Ltd., a wholly owned subsidiary of North American Palladium Ltd., owns and operates a 3000 t/d open pit mine and concentrate facility, located 100 km north of Thunder Bay in northwestern Ontario. The Lac des Iles PGE-gold-copper-nickel mine has been in commercial production since 1993 and in 1997, produced 1.8 million grams of palladium, 127 000 g of platinum, 114 000 g of gold, 438 000 kg of copper and 354 000 kg of nickel (North American Palladium Ltd., 1998).Under the Industrial Research Assistance Program (IRAP), a two-year study of the mineralogy of the Roby Zone was undertaken with a goal of improving the profitability of the mine. Geological mapping, petrography and geochemistry of the Roby Zone were completed during this study. Utilization of the detailed mineral/metal zoning identified as part of this study was implemented at the mine and shown to positively impact many operational aspects including mining and processing."

Jan 1, 2003