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By William W. Shilts

"In carrying out a geotechnical survey of a proposed gas pipeline route from the Arctic Islands south to Longlac, Ontario, the Polar Gas Consortium contracted the drilling of several hundred 2- to 2D-m-deep boreholes in drift and bedrock. Samples from these holes were made available to the Geological Survey of Canada, where they were subjected to stratigraphic and trace-element geochemical analyses. The geochemical characteristics of the clay and sand-sized heavy mineral fractions of till samples from these boreholes have been summarized in a series of geochemical profiles.From the proposed pipeline terminus at Longlac northward to the vicinity of God's River in Manitoba, tills contain significant amounts of Paleozoic carbonate rocks and Proterozoic sedimentary rocks derived from the Hudson Bay basin and lowlands. Within this section, two sites were enriched in base metals, indicating the possibility of local mineralization of possible economic interest.From God's River northward to Seal River, Manitoba, no evidence of local mineralization was noted. The heavy mineral fractions of the tills are universally enriched in Mn-rich siderite thought to originate on or in the Paleozoic section of the Hudson Bay lowlands.From Seal River northward to Thelon River, near Baker Lake, tills contain only components originating west of the Hudson Bay sedimentary basin. Near the Keewatin-Manitoba border, all till is enriched in uranium, which probably originates in the ""young"" porphyritic granites underlying much of the region, and produces a distinctive airborne radiometric anomaly.At the Thelon River, multiple till sections are variously enriched in Cr, Ni, U, Cu and Mo in the vicinity of a distinctive aeromagnetic anomaly.From Thelon River northward, several coincident zones of chromium and uranium enrichment are found where the line of boreholes crosses east-west-striking belts of volcanic, ultramafic and sedimentary rocks of the Prince Albert Group.The results of this study indicate that till tends to have characteristic element associations or concentrations over each of several broad regions along the pipeline route. These are related both to large-scale bedrock associations and to largescale effects of glacial dispersal. In addition, the samples, collected more or less at random with respect to local bedrock geology, have intersected several small-scale geochemical anomalies that appear to be related to zones of mineralization of possible economic interest."

Jan 1, 1980

By John D. Smith, Robert J. Mitchell

"There is a world-wide trend toward underground bulk mining methods employing hydraulically placed backfill. This trend is recent and therefore there is little in the literature to assist an operator in the design of backfill properties, the design of drainage facilities, the calculation of the operating forces on a bulkhead, and the control procedures considered necessary before, during and after pouring. This paper presents recommended procedures that are based on over to years of experience in the various aspects of backfilling large openings. Free-draining timber or concrete block bulkheads are shown to be a viable alternative to massive reinforced concrete bulkheads for the containment of backfill pours. Hydrostatic pressures cannot develop in backfills provided adquate drainage facilities are installed.IntroductionThe increasingly adverse relationship between mining costs and mineral values has led mining companies to develop more productive, lower-cost, bulk mining methods. This has led to the increasing use of large, more or less continuous, hydraulically placed backfill pours to enable the recovery of a higher proportion of pillar ore. The success of any bulk mining method depends on the degree of stability maintained during the stoping operations with reference to the mining rate, the performance of the backfill with respect to the per cent extraction of pillar ore, and the control of the mine structure with respect to safety and productivity. One such method has been previously described(I) where a steeply dipping orebody is being mined with a sub-level method that employs large, hydraulically placed tailings pours for delayed pillar recovery. The paper describes the rock mechanics analysis undertaken to establish the stope and pillar geometry and the approach taken to establish backfill strength requirements to prevent dilution during pillar recovery. Production with this method started in 1970 and because few, if any, large bulk pours had previously been used in- this way (judging by the lack of information in the literature), design data and criteria were needed for several aspects of the work. Methods to establish backfill quantities and pertinent ""in-place"" fill properties are described in 2, 3 and 4 in the list of references. Results of field measurements taken to establish fill pressures for bulkhead design purposes are described in 5 and 6. Laboratory large-scale model tests undertaken to confirm a fill strength design equation, which takes into account fill arching, have recently been completed. A paper describing these tests and the results will be forthcoming in the near future."

Jan 1, 1982

By X. X. Wu, Q. Zhang, R. H. Fan, Y. J. Feng, J. D. Liu, P. Z. Zhao

In the present study, AA6016 automotive sheets with different grain size were fabricated through changing fabricating parameters, and the effects of grain size on the bendability were studied by bending test and optical microscopy. The results showed that the sheet with coarse grains exhibited poor bendability, and some micro-cracks were revealed at the surface of the bending samples. While the sheet with fine grains exhibited good bendability, and the bending samples showed smooth surface. Shear bands on the cross section of bending samples were observed. It was found that samples with coarse grains had more shear bands. These shear bands distributed in bundles, which facilitated the formation of continuous neckings and micro-cracks. However samples with fine grains had less shear bands, which distributed uniformly. The decrease of grain size could not only hinder the formation of shear bands, but also improve the homogeneity of its distribution during bending. On the other hand, refining grains could increase the amount of grain boundaries, which impede the propagation of shear bands. Hence the decrease of grain size could hinder the formation of continuous neckings and micro-cracks during bending, resulting in the significant improvement of the bendability.

Jan 1, 2015

By J. Shahabpour

"Abstract - Breccias with angular and rounded clasts of a late-mineralization, ""barren"" hornblende porphyry dike set within a comminuted matrix consisting of rock fragments and quartz, cemented by quartz and K-feldspar of hydrothermal origin is observed in diamond drill cores from the Sar Cheshmeh porphyry copper deposit. Studies of age relationship between vein types, phyllic-altered clasts and the breccia groundmass suggest that the brecciation is a late event. The breccia clasts record evidence of hydrothermal reaction between the clasts and fluids responsible for the brecciation.Formation of bornite, in the breccia clasts of the originally barren hornblende porphyry dike, and in the breccia matrix, along with the scarcity of bornite in the Sar Cheshmeh deposit itself suggest involvement of fluids which are later and of different composition from the fluids responsible for the known mineralization at Sar Cheshmeh. These later fluids may be related to a later plutonic event and suggest the possibility of a later, and concealed deposit."

Jan 1, 1994

By J. H. Archibald

"In mines employing cut-and-fill stoping (sand fill), ore passes are built as mining progresses upward. These ore pass raises are generally made from timber and form a vertical ""chimney"", like a very tall log cabin. Traditionally the chimney, or raise, is square in shape and is constructed from square timbers with stepped ends as shown in Figure I. The timbered raise is thus surrounded by sandfill on its outside, leaving the centre open for passing ore down through it. Each layer consists of four timbers and rests flush on the layer below. The corners are frequently pinned or spiked.Under certain conditions in sandfilled stopes large horizontal loads may be transmined to the raise cribbing timbers, or the ""chimney's"" walls. In deep mines, where rock bursts are a problem, it can be shown that one of the conditions for rockbursts to occur is that the burst zone be stiffer and weaker than the surrounding rock(l). This allows a strain energy build-Up in the rock surrounding the burst zone, and the rate of release of this strain energy is known to be related directly to the over-all strength and stiffness of the rock in the burst zone. In stopes that are sandfilled, attempts are, therefore, usually made to increase the strength of the sandfill by the addition of large-sized waste rock and Portland cement. These measures usually achieve the desired strength of the sandfill and, consequently, the severity and frequency of rockbursts can be reduced.Problems may arise when the now chunky sandfill transmits high loads to the raise cribbing along with relatively large move- merits. This leads to heavily stressed and strained cribbing timbers the Coeur d'Alene district in Idaho, raise cribbing failures are common. A typical mode of cribbing failure is shown in Figure 2. One learns in statics that a structure shaped like the crib in Figure I is inherently unstable , at least from a structural standpoint. The crib has pivoted, in Figure 2, into a rhombi c shape and supports very little load. Soon the four-foot square raise cribbing made from 5 in. by 5 in. timbers will no longer pass ore."

Jan 1, 1991

What Bottleneck? ??Resurgence of BC Mining Industry; ??Climate of heightened activity ?Increases pressure placed upon regulatory agencies; ??Current EA and permitting system, when Federal agencies are involved, remains duplicative and inefficient ?not necessarily leading to better decision making; ??Inefficiencies will impederecovery

May 1, 2006

By A. A. Ruitenberg, L. R. Fyffe

"This paper compares several distinct types of mineral deposits associated with different families of granitoid rocks in the New Brunswick Appalachians. Porphyry copper deposit s are associated with late-stage differentiates of Lower to Middle Devonian I-type igneous complexes. Contact metasomatic deposits were formed where these plutons intrude carbonate rocks and they gave rise to vein deposits in fracture zones near wrench faults. The I-type granitoids were emplaced mainly in areas of thin continental crust and locally along prominent faults in areas of thick continental crust.In contrast, tin-tungsten-molybdenum-bearing greisen deposits and skarns, and antimony-bearing quartz veins are associated with predominantly S-stype granitoid complexes ranging in age from Middle Devonian to early Carboniferous. The mineral deposits occur within or along the contacts of very fractionated (specialized) late phases of these intrusive complexes, which are characterized by high K2O/Na2O, Rb/Sr and Rb/Ba, and low Fe, Mg, Zr and Ti contents. These specialized granitoids are in a large wrench fault zone that cuts across thick continental crust in southwestern and central New Brunswick.IntroductionA great variety of igneous intrusions and subvolcanic stocks were emplaced in the New Brunswick Appalachians during the latter stages of and immediately after the Acadian Orogeny (late Lower to Middle Devonian) and during the subsequent Hercynian Orogeny (Carboniferous). The presence or absence and characteristics of mineral deposits associated with these intrusions reflect the level of intrusion, the composition of the associated igneous rocks and the composition of the invaded sequences.Nickel-copper sulphide deposits occur in mafic intrusions in the St. Stephen area of the southwestern Magaguadavic - St. Croix Zone and in the Goodwin Lake area of the northeastern Mirarnichi Zone. Contact metasomatic and vein-type copper-rich base metal sulphide deposits and porphyry copper deposits with or without molybdenum are related mainly to high-level granitoid stocks of intermediate composition in the Matapedia-Tobique and northwest Miramichi zones. Tintungsten - molybdenum deposits with or without base metal sulphide minerals and antimony-uranium deposits are mainly associated with Upper Devonian and Lower Carboniferous biotite-muscovite granites and related 'subvolcanic intrusions that occur in an arc-shaped belt extending from the southwestern Magagaudavic - St. Croix Zone into the central Mirarnichi Zone."

Jan 1, 1982

By D. A. MacFadyen, J. J. Brummer, C. C. Pegg

"The first record of a kimberlite found in Canada (1946) was the identification of thin dykes intersected while drilling for gold in Michaud Township, Ontario.Sampling of the Munro Esker (1964) in the Kirkland Lake area, Ontario, by the Geological Survey of Canada identified the occurrence of detrital grains of pyrope garnets along a length of 35 km of the 113 km tested. A search for the source of the garnets resulted in the identification (1968) of a narrow subsurface kimberlite dyke in the Upper Canada Mine. This discovery resulted in a staking rush. Unfortunately, subsequent work did not identify the source of the kimberlite indicator minerals.During 1978 the Ontario Geological Survey started a multi-discipline study of 29 townships (2560 krn2) in the Kirkland Lake area, to encourage exploration for gold, base metals, and kimberlites. Back-hoe sampling (1979 to 1982), where the overburden was thin, and reverse circulation drilling, in areas of thicker drift, yielded samples of the till. These were analyzed for several elements and a mineralogical identification of the heavy minerals was completed. Pyrope and chrome diopside grains were identified.Studies of the Pleistocene geology indicated only the most recent direction (167 degrees) of ice advance (Matheson) and the associated deposits, out of a possible three advances known to occur in the general region straddling the Ontario-Quebec boundary, is present in the immediate area of Kirkland Lake. Contouring the distribution of pyrope grains (1990) showed a concentration centered over an area of 616 km2 extending down-ice from Gauthier Township. This included a smaller area containing chrome diopside grains. Kimberlite boulders were identified (1981) in gravel pits on the Munro and Misema River Eskers located within this anomalous area. The next step would be to use the airborne geophysical data to locate the kimberlite pipes which yielded the indicator minerals and boulders. The source area is likely to be in the northern half of the Ontario Geological Survey study area."

Jan 1, 1992

By H. Gharahbagheri, S. Shafiei Zadeh, H. Hassan Nejad, Reza Roostaazad

In this paper, dissolution of vanadium from mining residue, in which vanadium is associated intimately with magnetite ore, was investigated via both bacterial ( aerobic and anaerobic) and fungal activity. Although bacterial activity was tangible, it could not reduce and dissolve vanadium in both aerobic and anaerobic experiments. However, in fungal leaching, after 30 days about 36.9% and 29.7% of vanadium was dissolved for a pulp density of 10 and 30 g/l, respectively. At the end, the concentration of metabolites usually produced by fungal activity was optimized and oxalic acid was chosen as the main agent for the leaching process.

Jan 1, 2014

By J. J. Hussey

"Abstract-The ""Brunswick Horizon"" an informally named ore-bearing unit near the top of the Nepisiguit Falls Formation in the Ordovician Tetagouche Group, hosts the Brunswick No. 6 and No. 12 base-metal mines, as well as the former Austin Brook iron mine, in northern New Brunswick. Detailed structural analysis of the No. 6 and No.12 mines led to the prediction that a massive­ sulfide deposit may have been repeated by F1 folding along the Brunswick Horizon. A subsequent drilling program discovered the new massive-sulfide North End Zone at a vertical depth of 1100 m, 1 km north of the No. 12 underground workings. By the end of 1990, Zn-Pb-rich massive sulfides had been delineated over a strike length of 200 m and a down-dip extent of 170 m. Rock units intersected in the North End Zone are generally thinner and vary somewhat from those at the Brunswick No. 12 mine. Thinning of the hanging wall rocks may be primary, may result from attenuation along F2 folds, or may represent truncation by a thrust fault. The newly discovered sulfide zone indicates that significant potential exists for the discovery of other deposits at previously unexplored depths.SOMMAIRE-Dans le nord-est du Nouveau-Brunswick ""l'horizon Brunswick"" est le nom usuel de la zone qui contient les mines de métaux de base Brunswick No. 6 et No. 12, ainsi que l'ancienne mine de fer Austin Brook, toutes situées sur le dessus de la Formation ""Nepisiguit Falls"" dans le Groupe Tetagouche d'âge Ordovicien. Une analyse détaillée de la structure des mines No. 6 et No. 12 à permis a van Staal de prédire qu'un gîte de sulfures massifs pourrait se répéter dû à une déformation F1, au nord de Brunswick No. 12. Suite à un programme de forage, la nouvelle zone de sulfures massifs appelée le ""North End Zone"", profonde de 1100 rn, et à une distance d'un km au nord des chantiers souterrains, fut découverte vers la fin de l'année 1990, les sulfures massifs riches en Zn-Pb ont été délimités sur une longueur de 200 rn et une hauteur de 170 rn le long du pendage. Les unités de roches intersectées dans le ""North End Zone"" sont généralement plus minces et sont quelque peu différentes de celles de la mine Brunswick No. 12. L'amin­ cissement des roches pourrait être primaire ou être le résultat de l'atténuation le long des plis F2, ou soit tronqué par une faille. La nouvelle découverte d'une zone de sulfures indique un potentiel énorme pour la découverte d'autres g ""tes à ces profondeurs inexplorées."

Jan 1, 1992

The control of AG mills fed by ores with harder and softer components can be challenging due to the sensitivity of the mill to the ratio of hard to soft components. The mills at LKAB?s iron ore operations are generally well controlled, but there are periods when the throughput falls off dramatically, due to a loss of mill filling. As the ore is upgraded in the sorting plant through magnetic separation prior to milling, this presents an opportunity to manipulate the feed blend in advance. In order to assess this opportunity, a fullscale mill charge was dumped and assayed by size to quantify the build-up of competent waste in the mills. This was supplemented by pilot and locked-cycle laboratory tests at a wide range of feed blends in order to facilitate the development of an appropriate multi-component AG mill model. This paper reports the experimental campaign requirements and methodologies, as well as the major outcomes from analysis and modelling exercises using the industrial, pilot and laboratory multi-component data.

Jan 1, 2012

By John Hughes

1. De Beers, Diamonds and Canada 1.1. De Beers was founded long ago (1888, the same time that Canada became a country) in a rural mining village in South Africa. Today, we employ 22,000 people across 19 countries and have 14 mines including open pits, shafts, beach-sands and seabed. 1.2. Last year our sales were US$5.7 billion and our total production amounted to 47 million carats which means a 40% global market share. For the Kyoto buffs in the audience, the company consumes 66 million cubic metres of water per annum, 210 million litres of hydrocarbon fuel and 1,600 GWh of electricity. Stats are good, but aren?t as expressive as a movie. This one is 2 minutes long, which is quicker than I could elaborate. (Video 1 - 2 minutes) 2. De Beers in Botswana is the leading source of diamonds 2.1 Today Botswana is the Jewell in the Crown. There are three big open pits that enjoy economies of scale that make them the lowest cost producers. Last year 60 million tonnes of overburden and 30 million tonnes of ore were moved in Botswana alone. Botswana produced 31 million carats, compared to 14 million carats in South Africa and 2 million very high quality carats inn Namibia. 3. Diamond Mines provide feedstock? ?.to jewellery stores

Apr 1, 2005

Adsorption of guar gum was investigated on model minerals typically found in water-insoluble slimes of potash ores. The ionic strength of the adsorption mixtures was varied from distilled water to saturated NaC1 and KC1. The tests were also performed using a saturated brine. The adsorption density of guar gum on illite, dolomite, and kaolinite was found to be not only a function of total ionic strength but also of the type of electrolyte present in solution. Generally, the adsorption of the polymer on the clay minerals was higher in KC1 solutions than in NaCI, but the differences gradually disappeared when the electrolyte concentration approached saturation. The results were analyzed in terms of chaotropic (K ) or kosmotropic (Na') properties of background counter-ions and their different behaviors at the hydrated mineral-water interface. Guar gum adsorption on dolomite was related to the presence of calcium and magnesium sites on the mineral surface, and to the cis-configuration of OH groups of mannose units. Based on viscosity measurements, it was suggested that guar gum macromolecules form entanglements in NaCI solutions (and distilled water), but individual molecules exist in KC1 solutions thus creating different modes of adsorption of guar gum from concentrated NaCl and KCl solutions.

Jan 1, 2006

By Harry Piers

A RAPID glance over the history of The Mining Society of Nova Scotia shows that in its fifty years of service, which it is now rounding out, the Society has had an honourable career, rendered signal service to the mining industry of the Province, and helped to shape and improve legislation bearing on our mines and minerals, besicles publishing very many excellent papers and subsequent discussions thereon dealing with all subjects in its field of activity. THE GOLD MINERS? CLUB OF NOVA SCOTIA: The Society has the distinction of being generally regarded as the oldest mining fraternity in Canada ( 1). Iris the direct outgrowth or reorganization of The Gold Miners' Club of Nova Scotia, which was organized in March, 1887, at a period when the gold mining industry was very prominent in the Province. Mr. Geo. W. Stuart, who, in 1934, was the only living member of the parent association, informed me that the seventeen Charter Members of The Gold Miners' Club were John H. Anderson, Charles F. Andrews, A. B. Cox, Clarence H. Dimock, George E. Francklyn, L. W. Getchell, John E. Hardman, Alonzo A. Hayward, Major R. G. Leckie, W. L. Libbey, Edward M. McDonald, G. F. McNaughton, George A. Pyke, H. A. Sanders, C. E. Willis, Benjamin C. Wilson, and George W. Stuart. Others joined later in the same year.

Jan 1, 1937

By L. Cáceres, G. Leinenweber, P. Bustamante

"Given the severe scarcity of fresh water sources in Northern Chile the use of seawater has become the only alternative to allow mining expansion. This option however poses several technological challenges as a result of the high concentration of natural salts that promote various forms of metal corrosion. Therefore the steel piping protection has been a constant challenge for design engineers responsible for solving the problems of corrosion. Known protection alternatives are varied and expensive, a few of them are rubber coatings, protection based centrifuged concrete, extra wall thickness of pipes in combination with corrosion inhibitors, extra wall thickness of pipes without using corrosion inhibitors, and the use of highly corrosion resistant steel materials.In this framework the aim was to study the corrosion kinetics of carbon steel pipe API 5L X70 under electrochemical and weight loss testing. The test conditions include a range of seawater velocities between 0.2 to 3.0 m/s.For electrochemical experiments the API 5L X70 steel specimen was a 4 mm diameter disk embedded in an 8 mm diameter Teflon rod and exposed to seawater. Duplicated coupons were placed in a standard test apparatus that was built according to the standard ASTM D 2688 – 94.The main results were: a) corrosion mechanism explained in terms of the counterparts partial processes which are the hydrogen evolution and oxygen reduction reaction; b) for the test specimen a corrosion band like feature that suggest a lateral dispersion of aggressive solutions from corrosion pits; c) a range of corrosion rates between 1 and 1.96 mm/year for flow rates between 0.2 and 3.0 m/s; and d) a convenient inhibitor dose between 20–25 mg/L for optimum inhibition efficiency to obtain a maximum value of 80% for corrosion efficiency."

Jan 1, 2016

By Hamid-Reza Manouchehri

Coarse particles flotation is controlled by detachment (particle hydrophobicity and flotation cell turbulence) For composite particles (the bubble may attach to good hydrophobic region, but the expansion of the three phase line of contact is limited. Hence, the equilibrium contact angle, characteristic of the hydrophobic region, may never be attained, and the force of attachment is decreased relative to that possible for homogenous hydrophobic surfaces.

May 1, 2013

By T. Niedoba

Coal as an energetic raw material is characterized by many features that determine its quality. The data concerning coal are usually treated as independent values, despite the fact that this kind of approach is not always appropriate. In the paper the dependencies between sulfur contents and volatile components in coal and particle size and density were analyzed. The method of ordinary kriging is applied to experimental data to describe this relationship; this method can be used for particles of any size and density. An example of the application of this technique is presented for energetic coal Type 31, originating from one of the Polish hard coal mines in Upper Silesia. Results from ordinary kriging are in good agreement with experimental results. Similar analyses can be performed for other properties of coal material, such as ash content, Roga number, and moisture. On the basis of the data obtained by ordinary kriging, a more comprehensive multidimensional model is described, which can characterize certain deposits or strata from which the analyzed materials originate. This is superior to basing the model only on experimental data, which often is limited by size of the sample. The results obtained by ordinary kriging applied to various types of coal would allow more precise analysis of individual properties of the studied materials and increase the ability to determine significant differences between them. This method can be also applied to other types of mineral raw materials, such as copper ore.

Aug 1, 2013

By G. Girard, A. Larouche, J. Colbert, G. Doyer

"The Direct Chill (DC) casting process uses water to extract heat from molten aluminium and helps to control the solidification process. Many factors such as the water flowrate, water distribution around the mould and water impingement angle have significant impacts on the solidification process. It has been noted that the chemistry variation of the cooling water is also an important factor that has a major impact on the presence of defects on the ingot. A significant change in the water quality can produce defects on the ingots such as cracks, bleedouts, or runouts. Understanding the impact of water quality variation on ingots is therefore essential to ensure good ingot production and reduce defects. This paper aims at describing a new approach to follow the variations of process water quality over time. It is an original and innovative method, which is still under progress. A water quality and stability index (WQSI) is under development to evaluate changes in the water composition based on water physico-chemical parameters. The index is calculated by comparing each of the actual parameters with historical values previously modeled by a statistical law. It is a dimensionless number having an adjustable weight factor for each parameter. The positive or negative contribution of each parameter, with respect to the water cooling capacity, is taken into account to calculate the WQSI. The current selection of parameters is based on knowledge from the literature as well as on empirical experience. When the developed tool will be mature, it could be used to track water variations upon time and anticipate problems, enabling proactive actions to ensure good ingot production.INTRODUCTIONFor many years, the impact of water chemistry on heat transfer, during DC casting, has been of great interest in the aluminum industry. Several papers have been published to demonstrate the correlation between water chemistry and heat transfer (Yu, 1985), (Gildemeister, 2014). Although numerous studies do present the effects of water parameters (i. e. hardness, conductivity, oil, and grease…) on cooling capacity under controlled experimental conditions, they do not reflect the strong interactions between the parameters and variations present in a casting center. Wells and Cockcroft also demonstrated that laboratory based studies are not fully representative of real heat transfer in an industrial casthouse, there are too many factors involved (Wells, Li, & Cockcroft, 2001). In this context, it becomes very difficult to obtain a quantifiable relationship between the capacity of water to cool the ingot and ultimately the performance of the cast."

Jan 1, 2016

By Bétournay. M. C.

Advantages ?Safety ?Health ?Rapid, continuous development, productivity ?Stope dilution reduction Disadvantages ?High cost and long time for equipment development ?Hard rock mining condition limitations ?Size of equipment ?Equipment set-up time, down time ?Performance does not meet financial return targets ?Drill and blast retains advantage in cost, productivity, capital investment, application flexibility ?Stress accumulation issues in deep mining, ground support and material handling issues in weaker rock

May 1, 2009

By Lloyd H. Yeomans

"This paper will cover recent developments in conveyor applications with specific reference to capacities, bell speeds and distances. It will also discuss certain unique arrangements of horizontal, curved and loop belt systems. In addition, the recent changes in safety factors resulting from new conveyor construction methods will be reviewed.IntroductionConveyor belt systems are currently undergoing dramatic changes. Their use is being extended to providing a viable means for the transportation of bulk material over longer and longer distances.In this paper, a brief account of the historical development' of the belt is outlined, demonstrating how conveyor technology has adapted to changing market demands.Today, energy and environmental requirements are providing what may even be greater challenges. The ability of the belt conveyor to transport material and meet those requirements, places it in the position of replacing many conventional means of bulk material transportation.The paper also outlines some of the progress which has been recently made in this regard and includes a broad approach to the subject of belt design and application.Recent design developments have greatly extended the potential of conveyor belt systems to include applications thought impossible just a few years ago.Graphically illustrating the potential of this new technology IS a belting system currently operating in New Caledonia. Built in 1970, the system has an incredible centre distance of 43,000 ft, or about eight miles.Not to be outdone, the British Coal Board is currently constructing a belt system with a centre distance of 49,000 ft and a speed of 1,650 feet-per-minute. This system is expected to be completed in 1986.These innovative advances contrast dramatically to the conveyor belt's beginnings in the early industrial revolution. Oliver Evans, writing in the 1795 edition of 'Miller's Guide' defined the conveyor belt as a ""broad endless strap of thin pliant leather or canvas, revolving on two pulleys in a case or trough.""Obviously, the conveyor belt has come a long way since those early days."

Jan 1, 1983