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By P. J. Mehrfert

"Recovery of mineralized coarse particles is notoriously low in conventional concentrators that treat copper porphyry ores. The application of coarse particle flotation techniques has the potential to achieve comparable metallurgical performance at significantly coarser primary grind sizings. ALS Metallurgy has been conducting both internal research and commercial test programs to investigate the potential of Eriez HydroFloatTM technology on copper sulphide ores. Test data indicates that significant improvements in the recovery of copper sulphide bearing particles between 200µm to 850µm can be achieved using Hydrofloat technology compared to conventional flotation techniques. This paper summarizes the results from a selection of test programs that includes recovery by size data from both conventional flotation and HydroFloatTM tests. An explanation of the apparatus and test procedure will be given. Mineralogical analyses of the test products and characteristics that limit metallurgical performance will be discussed.Description of Apparatus and Test ProtocolThe HydroFloatTM laboratory cell is a clear plastic column with an internal diameter of 14 cm. Water and air are introduced to the cell through a circular manifold located in the lower portion of the cell. The cell has a conical bottom which directs slurry to a pinch valve that controls the discharge of tailings. Feed solids are introduced to the upper portion of the cell in slurry form. The cell is operated in a manner such that the manifold water creates a teeter bed zone of suspended solids in the middle portion of the cell. Tailings exit the bottom of the cell at a high pulp density, and most of the introduced water overflows the top of the column and is collected in a launder. Particles with a hydrophobic surface may attach to air bubbles that percolate through the teeter bed, rendering them sufficiently buoyant to be transported to the overflow launder.Three significant features of this arrangement enhance the potential to recover coarse, low grade particles by flotation techniques. Firstly, the hindered settling conditions created by the rising column of water allow coarse particles to become buoyant once attached to a modest sized air bubble. Secondly, the flow conditions within the cell are relatively quiescent compared to a conventional flotation cell that utilizes an agitator. This allows particles that have limited hydrophobic portions of their surface, due to a low content of exposed sulphide mineral, to maintain a somewhat fragile attachment to air bubbles long enough for successful recovery to the overflow. Finally, the absence of a froth phase at the top of the cell allows particles attached to air bubbles to immediately exit the vessel, reducing the potential to drop back into the pulp phase as bubbles burst or coalesce."

Jan 1, 2017

By Andre Vien, Jean-François Dupont

"Over the past several years, Svedala has developed a continuous charge monitor (CCM) for tumbling mills. It consists of a strain gauge embedded into a rubber lifter and associated electronics. This paper describes the installation and use of such a device on a SAG mill at the Holt-McDermott Mine. Comparison to measured static volumetric load and bearing pressure and inclusion of the measurement into a control strategy and its potential for condition monitoring is discussed. INTRODUCTIONWhile the measurement of load is very important in all kinds of grinding applications, the biggest benefits are expected from AG and SAG milling. This is what motivated Holt-McDermott to take a closer look at this problem, with a view to optimizing SAG mill performance.In many cases, the SAG mill control problem can be stated as maximizing throughput while avoiding a volumetric overload, with the other constraints (e.g. power, grind size, upstream/downstream equipment constraints, etc.) playing a less important role. This is certainly true at Holt-McDermott where the SAG mill is the production bottleneck about 90% of the time, and anything that can be done to increase SAG mill throughput will have a significant impact on operating profit.Although the goal of maximizing throughput while avoiding volumetric overload is simple to state, it has proven to be much more difficult to achieve. The mineral processing industry has expended a great deal of time and effort to devise control strategies in the pursuit of this objective. While much progress has been made, there is still room for considerable improvement. Across the industry it is probably fair to say that overloads occur relatively infrequently, but the real losses accrue as a result of the tendency to run rather conservatively."

Jan 1, 2001

By D. J. Hutchinson, M. Lato, M. Diederichs

Light Detection and Ranging (LiDAR)-based applications for geomechanical purposes have recently proven to be a highly reliable and accurate form of remote analysis and documentation. The ability to remotely collect, process and evaluate rockmasses for structural geomechanical applications has benefits ranging from safety to efficiency, and provides a permanent record that can be assessed before and after an excavation has been completed. With the collaboration of Queen’s University and Rio Tinto, the Iron Ore Company of Canada (IOC) mines in Labrador City, Newfoundland and Labrador, evaluated the practical application of the I-Site 4400 LiDAR equipment, in conjunction with the Vulcan geotechnical module for geomechanical purposes. The project provided a comparative analysis between conventional hand-mapping and digital analysis. The analysis indicates that digital mapping could be employed as an active tool within the general geotechnical workflow, where results would be used in pit wall and rockmass support designs. As well, the field work enabled the generation of effective operational guidelines and protocols to maximize scanning efficiency.

Jan 1, 2009

By R. J. C. MacDonald

"The first recorded discovery of placer gold in Canada was on the Chaudiere River in Quebec's eastern townships in 1832 and the first major production came from placer deposits in British Columbia in 1858 (Verity 1974). Placer deposits were the major source of gold until the late 1890's, although lode deposits were found in Nova Scotia in 1862. In 1896 the Klondike Gold Rush commenced with the discovery of gold by Henderson and Carmack in the Yukon. The peak was reached in 1900 when over one million ounces of gold valued at approximately $22.3 million were recovered. With the exhaustion of the easily accessible deposits, more capital intensive operations were necessary such as those initiated in 1906 by the Yukon Gold Corporation. This giant dredging operation continued to produce until 1966. Today only a few small operations remain.The development of Canadian lode gold mining began in earnest around 1900 when the railroads were opening up the interior and western part of the country. At this time many discoveries occurred, particularly where mineral outcroppings were near surface. Tremendous impetus for exploration and the reopening of former producers followed the elimination of the gold standard by Great Britain around 1931, and more importantly the United States in 1933, with subsequent stabilization of the price of gold at $35 per ounce in 1934. Prior to this the price of gold was basically unchanged since 1717, approximately, $20 per ounce (Verity, 1974; Green, 1973).The depression of the 1930s adversely affected most industries, however for the gold producers it was a very profitable time. Prices of materials and equipment declined and labour was cheap and plentiful. Interest in gold mining was further stimulated in 1936 when a three year tax exemption was declared for all new metal mines. In 1938 a decline in the value of the Canadian dollar relative to the U.S. dollar benefitted the industry. The second world war provided yet again further incentive for gold production and in 1941 Canadian gold production reached a high of approximately 5.4 million ounces. This figure was not surpassed until 1991 when approximately 5.6 million ounces were produced (Natural Resources Canada, 1996 )."

Jan 1, 1998

By Hamid-Reza Manouchehri

Mining & Sustainability? A Paradox?! ? Production: gradually or exponentially increasing (giant mining) ? Ore Grades: gradually declining, ? Open Cut Mining: now widespread, likely to be sustained in the future though the long-term is hard to predict as new mineral deposits are likely to be deeper ? Waste Rock / Overburden: increasing rapidly, likely to be sustained in the future and closely linked to open cut mining, especially for coal and base metals ? Economic Resources: commonly increasing but some remain stable or gradually declining, future is linked closely to exploration, technology and economics; Increasing population, changing life style and technology development, ultimately result in sustainability in mining industry to hang in the balance and continue.

May 1, 2013

By H. Warren Newcomen

The southwest wall of the Lornex Pit at the Highland Valley Copper mine has been experiencing slope displacements since 1978. Measures to manage the displacements on previous pushbacks have included stepping out, scheduling pushbacks to unload the crest of unstable areas, slope dewatering and mining with intensive slope monitoring. The final pushback on this wall is currently being mined and substantial modifications to the slope geometry could prove to be uneconomic. As a result, a campaign of surface water collection and diversion, horizontal drainhole drilling and deep well drilling is currently underway to maintain an acceptable degree of stability to the end of mine life. The various factors contributing to instability, including engineering geologic controls, rock mass strength, and surface and groundwater hydrology are presented. Movement trends, displacement magnitudes and stability analyses results are also discussed.

May 1, 2002

By Bern Klein, Randy Blaskovich, Reem Roufail

"Morphology is a tool that is rarely used for mineral breakage mechanism evaluation. Ground particles are typically assessed for their size distribution. They are also visually analyzed using image analysis. However, image analysis is not a comprehensive evaluation of the particle surface texture. It evaluates particle’s size parameters such as area, diameter, and perimeter amongst other features. On the other hand, morphology analysis takes the particle assessment to another level of detail. Morphology analysis evaluates particles’ roundness, elongation and angularity that would indicate the degree of roughness of the particle. According to Roufail and Klein (2009), rougher surfaces are generated due to breakage along grain boundaries – intergranular breakage. Mill operation, particularly mill speed, dictates the dynamics in the mill. Stirred mills are known to break the particles via abrasion under standard operation. However, if the dynamics of the grinding media in the mill are changed, the particles could be more exposed to impact and compression loading that would lead to a different mode of breakage.In this paper, the effect of material properties and mill operating conditions on particle morphology will be studied. Hard non-sulfide versus soft sulfide minerals are compared, namely quartz and galena, respectively. Extreme mill speeds are tested covering the range of 1000 to 2000 rpm for a 4-litre Netzsch (ISA) mill. In addition to particle size distribution, micro-analysis is executed in the form of morphological analysis using a tested manual roughness point counting technique.INTRODUCTIONGrinding in general and stirred milling in particular are processes that are used to break particles to liberate metal-bearing minerals for further separation downstream. The energy required to achieve the target particle size versus maximum possible liberation has been studied intensively and it is usually the breaking point for the grinding system chosen in a process flowsheet. Operating conditions are dictated by the energy consumption. Becker et al. (2001) related different forms of energy such as input, specific, volume/mass specific energies to stress intensities and final product fineness. Other research studies focused on energy input in a stirred mill (Zheng, Harris and Somasundaran, 1996)."

Jan 1, 2011

By Gaby Steinbach

A novel synthesis is described for the preparation of supported gold catalysts for low-temperature CO oxidation. The novel route is a variation of the inverse co-precipitation method and requires amphoteric metal hydroxides, with zinc and aluminium hydroxides chosen. Catalysts were prepared by inverse co-precipitation (ICPa) and by the novel route (ICPb) and tested for CO oxidation at 60ºC. Preliminary results showed the novel route to be superior to ICPa; the catalysts prepared by ICPb showed higher catalytic activities. The effect on catalytic activity of parameters such as pH, calcination temperature, washing of precursor and calcined catalysts and ageing was investigated. A preparation pH of 9 and a Zn to Al mass ratio of 3 proved to be optimal. It was possible to remove residual chloride by washing thereby enhancing catalyst performance. Ageing and Mg citrate addition were also shown to improve catalyst performance. Characterization of the catalysts revealed that better activities were obtained when the support was more crystalline and had a higher surface area. The presence of carbonate-containing species in the support decreased catalytic activity. 197Au Mössbauer Spectroscopy revealed the presence of Au3+ when catalysts were heat-treated at temperatures of 200ºC and below. Catalysts calcined at 400º had 75% of the gold present as Au0, with the remaining gold present as Au3+.

Oct 1, 2003

By N. W. Byrne

THE study of diamond drill results at the Lake Athabaska property of Athona Mines, Limited, and the co-ordination of information secured, has demanded extensive application of methods for interpreting true conditions, both structurally and from the point of view of ore outlook. This work was in charge of a capable engineer, who, as the result of exhaustive study of the drill cores, has been able to issue maps and plans exceeding the expectations of the majority of engineers and geologists who visited the field during the past summer (1935); that is, having in view the fact that staking of the property had been completed but a few months beforehand and that geological conditions were practically unknown up to the time drilling began in April. The following pages present an outline of the work of the assay and engineering offices in co-ordinating and interpreting the results of the drilling. The writer desires to acknowledge the suggestions offered by A.P. Beavan, geologist and engineer at Athona Mines, whom he assisted during the drilling campaign, and also the co-operation of the drilling contractor's employees. The geological map, mine plans, and forms accompanying the paper are from the Company's engineering office files.

Jan 1, 1937

By Jessica E. Heuchan

An industry survey has been conducted by the Queen's University Mining Engineering Department of 30 Canadian mining organizations to determine how effectively newly graduated mining engineers meet the needs of the industry. The principal objectives of the survey were to evaluate, and thus provide focus on change for, curricula being taught at Canadian mining engineering schools in service of the industry's needs; to provide feedback on current industry expectations; and to reinforce contacts with the industry as a means of providing future collaboration. A strong focus of the survey was placed upon industry's perception of the special attributes of engineering hires and applicability of student academic training to meet their industrial requirements. In providing this detailed summary of corporate responses, a clearer understanding of the mining industry's expectations of engineering training at Canadian colleges and universities has been gained.

May 1, 2003

By K. Woo

The increasing move to block cave mining methods (including sublevel and panel caving) to access deeper and lower grade ore deposits as near surface sources become exhausted raises questions as to the extent and magnitudes of caving-induced subsidence as it may affect strain-sensitive infrastructure on surface. Predicting these surface deformations is difficult as they tend to be discontinuous and asymmetric due to large movements around the cave controlled by geologic structures, rock mass heterogeneity and topographic effects. Of further impediment is the sparse number of case histories available, in which actual subsidence measurements are reported to provide guidance and empirical constraints for subsidence calculations. This study reports the development of an exhaustive and comprehensive database of available (i.e. public domain) subsidence data from block cave mining operations from around the world.

May 1, 2009

By F. Malek

At Creighton Mine, magnitude events are a regular occurrence due to depth and major seismically-active structures. Over the last ten years, major advances have been made in research and development to develop strategies for the management of these major events. Today, the number of rockbursts has been drastically reduced at the mine and damage due to seismic events, when they occur, is often minimal. This paper describes the evolution and implementation of appropriate geomechanics strategies, designs, and practical ground control measures undertaken for the management of seismicity at Vale Inco?s Creighton Mine. A description of the research and development approach, implementation, and ground control strategy is provided for placement of enhanced support systems to manage the consequences of magnitude events at Creighton

May 1, 2009

By Ben Murphy, Tomi Maksimainen, Antti Rinne, Ishmael Muzinda, Toni Mattsson

"A 500m3 flotation cell was commissioned during 2014 at the Kevitsa Mine in northern Finland working as the first rougher in the copper flotation circuit. Treating around 850tph with an average grade of 0.3% Cu, the TankCell® e500 has run with an average copper recovery of 71% and an average enrichment ratio of 50 during early optimization test work. In addition the cell has proved to be very energy efficient, being operating with a specific energy of around 0.4kW/m3 under production conditions.A review of the installation and operation of the TankCell® e500 at Kevitsa will be presented. Metallurgical performance of the cell during the operating period will be discussed on the basis of on-line analysis and the metallurgical samples collected during early optimization campaigns.IntroductionThe past three decades have seen a rapid increase in the size of mechanical flotation cells. This has been largely driven by demand from the copper industry to process larger volumes of material due to combination of declining head grades and the desire to benefit from the economies of scale (Lynch, Harbort and Nelson 2010). During this period Outotec has been at the forefront of development of large flotation technology with an enviable scale-up track record; 100m3 (1995), 160m3 (1997), 200m3 (2002), 300m3 (2007), 500m3 (2012) to the largest commercially available cell at 630m3 in 2013. This scale-up methodology has been developed, tested and validated (Elgueta et al., 2009; Coleman & Dixon, 2010) by the large installation base of cells in the 300m3 size class operating (over 400). The learning from large cell operation are then reviewed and incorporated back into new designs and scale-up practices (Murphy, Miettinen, and Yanez, 2014)."

Jan 1, 2016

By Laszlo Imreh, Pierre Trudel, André C. Tessier

"The Siscoe gold mine is ranked as the fourth largest mine in the history of the Val d' Or mining district with a total production of 27.4 tAufrom1929 to 1949. Most of the gold mineralization occurred in quartz veins, hosted in a small (.69 km2) intrusion of altered quartz gabbro known as the Siscoe stock. The southern contact of the Siscoe stock is crosscut by a major shear zone (the ""K"" zone) trending 295/80 NE and from which gold mineralization was also exploited within the limits of the stock. Field and petrographic observations of the Siscoe stock combined with chemical analyses of major, trace and rare earth elements of the stock and its volcanic host rocks (Dubuisson Formation) suggest that:The Siscoe stock comprises four alteration facies formed from a homogeneous precursor: 1) the actinolite - Mg-chlorite facies, characterized by low FeOt,Na2O andTiO2 , and highAlp3 and MgO; 2) the albite- Fe-chlorite facies, containing high concentrations of FeOt and Nap; 3) the Mg + Fe-chloritefacies, which is transitional between the actinolite- Mg-chlorite and albite- Fe-chloritefacies; 4) the carbonate-chlorite facies, which consists of rocks that were subjected to extreme hydrothermal alteration, is spatially associated with mineralized veins and part of the K-zone. The first three facies are depleted in SiO 2, CaO and Au, and enriched in MgO, relative to fresh rocks of the Siscoe stock and the equivalent rocks of the Dubuisson Formation.Hydrothermal fluids introduced mainly along the K-zone ""channelway"" induced three types of element remobilization, resulting in the various alteration facies: 1) redistribution of elements within the stock from one facies to another (e .g., FeOt, Nap, Ti02 migrated from the actinolite- Mg-chlorite facies to the albite- F e-chlorite and Mg + Fe-chlorite facies); 2) remobilization of elements from the intrusive rocks into veins (e.g ., SiO 2 and CaO ); 3) introduction of elements by hydrothermal fluids in rocks of the Siscoe stock (e .g., Al2O3, MgO, H2O, CO2 and FeOt).The Siscoe stock and the Dubuisson Formation form part of the same tholeiitic suite. Similarly, the Bourlamaque batholith and the Val d'Or Formation belong to a single calc-alkaline suite. In view of this relationship, dissimilarities between the petrochemistry of the Siscoe stock and the Bourlamaque batholith suggest that the two intrusions are not co-magmatic.Finally, gold may have been leached from rocks of the Siscoe stock and remobilized into the quartz-carbonate mineralized veins. In order to account for the total production at the Siscoe mine, approximately 1.2 km3 of the Siscoe stock is thought to have been partially leached of its gold."

Jan 1, 1990

By Eric Konigsmann, Doug Spence, Scott Jones

"The Williams Gold Mine is located in the Hemlo camp of Northwestern Ontario and is one of Canada’s largest gold producers with annual gold production of 400,000 ounces. The operation is owned and operated as a 50:50 joint venture between Teck Cominco Limited and Barrick Gold Corporation.In July 2002, the decision was made to introduce paste backfill produced from mill tailings as the primary backfilling method in the mine and to decommission the existing cemented rock fill system. This required a fast track design to be completed for both a surface paste backfill plant and an underground paste distribution system followed by an intensive construction phase through the fall and winter of 2002/2003. The paste system was commissioned on schedule in late April 2003 and was in full production within 4 weeks of the initial start up. Overall, the project duration was only 42 weeks from initial project release to commissioning and it was completed $2 million under the budget of $14 million.This paper presents an overview of the lab testwork and process flowsheet design, process control methodology and describes the construction and commissioning phases of the project. Preliminary paste plant performance and operating cost data is also presented.IntroductionThe Williams Gold Mine is located in Northwestern Ontario adjacent to the Trans Canada Highway in the Hemlo Gold Camp as shown in figure 1. The mine currently produces approximately 400,000 ounces of gold annually and is owned and operated as a 50:50 joint venture between Teck Cominco and Barrick.The deposit was discovered as part of the Hemlo gold discovery in 1981 which led to the development of three mining operations within a 2 kilometre radius. The neighboring operations are the Golden Giant Mine, currently owned and operated by Newmont Gold, and the David Bell Mine, currently owned and operated by the same joint venture which is running Williams. David Bell ore is blended and milled in the Williams concentrator."

Jan 1, 2004

By P. Quinn

"The Venturi-aerated flotation column (VAC) is based on a reactor and separator design for a new generation of flotation machines. The reactor is a Venturi tube, where the air/slurry contact takes place with intensive aeration for efficient particle collection. The separator is a column of 1-3 m length that provides quiescent hydrodynamic conditions for effective separation of bubble-particle aggregates from the remaining slurry.Aeration in the Venturi tube occurs via two mechanisms: air dispersion and nucleation (cavitation). By forcing air through a restricted passage with a fast flowing slurry stream, air is dispersed into fine bubbles. Bubble formation due to cavitation occurs on the surface of particles in the low-pressure section of the Venturi, from dissolved air contained in the liquid.Size-by-size recovery and flotation rate constants were determined for a small-scale laboratory Venturi-aerated flotation column. The results were compared to those obtained in a laboratory 2.2 L Denver cell. It is shown that the Venturi-aerated flotation column has slightly slower flotation kinetics to the Denver cell, but with much higher flotation selectivity. A portable Venturi-aerated flotation column can effectively be used to investigate process or equipment problems in operating plants.INTRODUCTIONFlotation processes can generally be divided into two sub-processes: 1) selective collection of hydrophobic particles by air bubbles and 2) separation of bubble-particle aggregates from hydrophilic particles that remain in the pulp. The methods of aeration, or bubble generation, control the mechanism of particle collection by either collision with, and subsequent attachment to bubbles, or by in situ bubble formation on the surfaces of hydrophobic particles. A flotation device should provide optimal aeration conditions for efficient particle collection and a suitable hydrodynamic environment for effective removal of bubble-particle aggregates from the remaining pulp."

Jan 1, 2002

By C. M. Diaz, S. W. Marcuson

In the late 19th century, the discovery of rich nickel-copper sulfide ore bodies in Sudbury and the need for tonnage quantities of the metal to be used in nickel steel armor provided the foundation for establishing the Canadian nickel industry. For almost 50 years, International Nickel was the key player. In 1930, Falconbridge Nickel entered the field. These two companies remain the key Canadian nickel producers. This paper discusses the factors that have influenced the evolution of nickel smelting processes. The initial Sudbury ore smelting and nickel copper separation technologies were imported from abroad. It was only in 1937 that International Nickel established a process research laboratory in Copper Cliff The explosive post WW II industrial development created a strong demand for a broader variety of nickel products. For both International Nickel and Falconbridge, R&D became an essential business tool to succeed in the new market scenery. In the last few decades, new technologies were developed and commercialized to respond to the raising cost of energy, society pressing environmental concerns, the advent of nickel laterites as an important source of new metal, the incorporation of new nickel producers to the market, and, therefore, the need to increase productivity. Canada thus became an important exporter of technology. In this paper, the authors review this history with the objective of highlighting the forces that have triggered the most important changes in Canadian nickel smelting.

Jan 1, 2005

By R. J. Munday

Although uranium deposits in northern Saskatchewan are clustered around the Athabasca basin, basement lithostructure determines their distribution. Basal Wollaston Group pelites are invariably graphitic and carry uraninite in felsic segregations and biotitic pegmatite. Where these intersect the Athabasca Formation, remobilized uranium concentrated as pitchblende. Uranium is also concentrated in silicified and hematized sandstone where the Athabasca Formation overlies post-orogenic faults. Presumably, pregnant solutions associated with the fault were stripped of their metals as they emerged into the contrasting physico-chemical environment of the sandstone basin. Both these types of mineralization correlate with a Grenvillian (-1,000 m.y.) heating event and associated diabase intrusions. However, the rich pitchblende veins at Uranium City appear to predate the Athabasca Formation, but display spatial correlation with the Martin Formation. They are tentatively associated with a syn- to post-D3 retrograde metamorphic event which thoroughly leached crystalline basement and generated uraniferous fluids which escaped, and precipitated metals, into fractures associated with faults that define the grabens in which the Martin Formation was deposited. Remobilization events allowed some of this uranium to move upward into fractures within Martin sediments.

Jan 1, 1979

By R. Patrick

As a unique South African organisation, CSIR: Division of Mining Technology (Miningtek) strives to support the mining industry by improving health, safety and productivity through developing, adapting and transferring technology. Considerable effort is currently directed towards the development of potential non-explosive mining methods with the potential to allow continuous mining in narrow reef conditions. Besides improving productivity, continuous mining results in concentrated mining which has a significant impact on reducing infrastructural costs. Impact Ripping and Water Pulse Rock Breaking have been tried on gold mines, whereas Activation, Mini-Disc? cutting and the Plasma Holemaker are currently being tested on platinum mines. The organisation?s many years of experience in novel rockbreaking, together with its world-wide collaborator network, has placed it in a unique position to assist the mining industry and manufacturers in developing and/or adapting existing technologies for application underground. Currently a range of technologies are being investigated, which have reached different stages of maturity. The main technologies under investigation are; - Impact ripper system - Water pulse rock breaking - Activated undercutting rollers - Mini disc cutters - Electric rock breaking

Oct 1, 2001

By Donald J. Hallbom

"While pipeline hydrotransport is often the most economical way to transport large volumes of mineral concentrate, tailings, or fine ore slurry over long distances, it is in mountainous terrain that pipelining becomes particularly attractive. These areas are often remote, with limited existing infrastructure and few potential users willing to share in the cost of new infrastructure. The rugged terrain makes the construction of railways or roads suitable for haul trucks difficult and expensive. The elevation difference between the mine and the terminal means that the empty trains or haul trucks need to return up-hill, resulting in high fuel costs. With pipelines, this elevation difference may reduce or even eliminate the need for pumping. As a result, numerous pipelines have been built, or are being considered, in mountainous regions around the world including: Tasmania, New Guinea, China, Madagascar, the Rockies of North America, and the Andes of South America. However, there are technical difficulties that need to be overcome in the design and operation of mountain pipelines that do not affect pipelines on more level terrain. This presentation reviews some of these difficulties and methods used to overcome them.INTRODUCTIONPipeline transport of solid-liquid slurry (“hydrotransport”) is an important and cost-effective means of transporting large volumes of solids over long distances, especially from a single supplier to a single user (e.g., a concentrator to a port, a concentrator to a tailings dam, or a coal mine to a power plant). Pipelines are generally found to be more economically attractive than alternate transportation methods (e.g. trucking, rail, conveyors, shipping, or some combination) over the life of a project (Aude et al. 1974).Hydrotransport systems have been built in a variety of terrains, but it is in mountainous regions that pipelining becomes particularly attractive. These regions are often remote and generally do not have existing transportation infrastructure (roads, railways, navigable rivers). There are few potential users (e.g., farmers, other mines, forestry companies, etc.) who may be willing to share in the cost of new infrastructure. The rugged terrain makes the construction and maintenance of railways or all weather roads suitable for large haul trucks difficult and expensive. Mines tend to be higher than the receiving terminal (e.g. a port). This means that the empty trains or haul trucks need to return up-hill, resulting in high fuel costs. With pipelines, this elevation difference may reduce or even eliminate the need for pumping. Pipelines are easier to construct than roads and railroads in these areas for several reasons, including:"

Jan 1, 2006