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By Dennis Ofiara, Michael Lewis

An experimental 1.75 meter Shaft Boring Machine was designed and manufactured by The Robbins Company. The drill was used by contractor Drillcon Raise AB to drill test shafts at an SKB underground test facility. SKB is the Swedish authority responsible for safe management of nuclear waste materials. This “SBM1.8” Shaft Boring Machine was used to drill shallow test shafts ingranitic rock at SKB’s Aspo underground laboratory. The drill used a unique vacuum mucking system. The bored shafts were held to very strict tolerances for bore diameter, straightness, and verticality. This drill was launched and operated from a mobile launcher. Headroom and working space were limited. The SBM1.8 drill produced acceptable test holes. SKB will carry out several studies to determine the suitability of this geology, and of this technique, for safe nuclear disposal. In addition to future use at SKB, many applications are foreseen, particularly in the civil construction industry.

Jan 1, 2005

By G. J. van Tonder

The use of Molecular Recognition Technology (MRT), a highly selective separation technology using specifically designed ligands (such as macrocycles), has been demonstrated to be an effective treatment process for removal of several ions that are commonly found in many hydrometallurgical circuits as well as in environ-mental treatment operations. Ions removed by MRT include base, heavy and transition metals, precious metals, halides, and alkali/alkaline earths. A MRT pilot plant run was conducted at Zincor to demonstrate the cobalt/nickel purification of zinc electrolyte, and to recover saleable pure cobalt/nickel sulphate solution. The MRT process holds various advantages, which include the elimination of a catalyst such as arsenic trioxide, conventionally used in cobalt and nickel cementation. SuperLig® 138 can be used to remove cobalt and nickel from120?170 g/l Zn-solutions at pH 1?2. The Zincor MRT application demonstrated its capability of concentrating large volumes o copper barren impure solution at low cobalt and nickel concentration levels in the feed, to small solution volumes at high cobalt and nickel concentrations. Around 99.5% of the cobalt was removed from solution with cobalt impurity levels in feed varying between 10 mg/l and 26 mg/l.

Jan 1, 2002

Regions with extensive reserves of brown coal but with inadequate deposits of hard coal provide a particularly suitable field for the application of brown coal petrology.In fact, this discipline is indispensable where brown coal is to form the basis for high-quality products of upgrading. Both chemical and physical analyses are required in addition to the techniques employed in coal petrology, but it is the macropetrographic and the microscopic investigations that are of decisive and specific importance.Foremost among the methods of upgrading brown coal is briquetting. From the raw materials aspect the biochemical rank of coal (i.e. the type of deposit) and the coal variety (i.e. the lithotype) exert a marked influence on briquette strength. These are also the significant factors in the suitability of a brown coal for high temperature carbonization; here the demands on coal quality are even more exacting if adequately sintered and therefore high-strength lump chars are to be obtained. The principle applies also to the char from low temperature carbonization. There are close relationships between the tar yield and the remission of the coal.The reflectivity measurement therefore provides a rapid method for evaluating the suitability of a brown coal for low temperature carbonization. Similar correlations have been established between the content of extraction bitumen (raw montan wax) and the remission. Petrological investigations show that the quality of the coal bitumen is a function of the type of deposit and of the lithotype.

Jan 1, 1968

Atlas Copco Wagner launched its ST1010 Scooptram load haul dumper. The ST1010 replaces the company’s Wagner ST-1000 Scooptram. The improvements to the Wagner ST1010 include increased reliability, ease of maintenance and driver comfort or ergonomics. The ST1010 has been redesigned and has added several new features and options not offered in the earlier model. These include anew boom design with side stops. Heavy reinforcements to the bogie offer better protection against the harsh working conditions in underground mining and tunneling. An auto lube system has also been added as has paint-on grip tread to reduce slips and falls during maintenance checks or repair work. Other features include a heavy-duty, auxiliary-fan motor, an isolated transverter, remote diagnostic pressure taps, a bolt-on battery box, raised air-intake, improved fuel-filter access for easier maintenance, larger wear-bars around the engine tub, and smaller, higher output batteries

Jan 1, 2000

The effect of composition on electrical conductivity (resistivity), viscosity and liquidus temperature of the slags encountered in electric smelting of PGM containing suphide concentrates is reviewed, along with the relationsip between slag composition, slag-matte separation and metal losses to slag. Optimization of slag composition at furnace temperature is attempted on the basis of opposite and parabolic trends of the viscosity-conductivity relationships of the slags. The importance of surface tension of slags is emphasized using available and estimated information which are grouped into a useful correlation. These values are coupled with or incorporated into slag viscosity plots to illustrate the correlation between the two factors, which influence slag-matte separation as well as refractory attack. The electrode in the slag-resistance furnace is the central factor in the design and operation of the furnace by its role of conveying the smelting power. The obvious parameters are the size and positioning in the slag bath, which are defined by slag resistively, furnace resistance, cell constant and power input. The flow of heat generated by the electrode current determines the energy distribution and furnace dimensions creating viscosity profiles, which in turn affect flow conditions. Thus the flow of slag and matte are discussed in conjunction with the furnace geometry, stirring action of the electrodes, buoyancy and electromagnetic effects. The action of the electric furnace as a settler is discussed. The rectangular furnace is considered as a channel reactor in this analysis, and the action of the electrodes is described to indicate a balanced settling rate in the area of electrode action. Discussion of the design and production capacity of the electric furnace, with reference too perating current, power input, furnace dimensions and electrode size, are based on considerations derived mainly from slag properties such as its resistively, viscosity and liquidus temperature.

Jan 1, 2004

By C. M. F. Vieira

This work has as its objective to characterize ceramic bodies for vitrified tiles elaborated with the mixture of nepheline-syenite flux and kaolinitic clay. Formulations were prepared with 0, 30 and 50 wt.% of nepheline-syenite incorporated in a kaolinitic clay. To determine the physical and mechanical properties such as dry bulk density, linear shrinkage, water absorption and flexural rupture strength, specimens were prepared by 30 MPa uniaxial pressure-molding and then fired in a laboratory furnace at 1150oC. The microstructure of the fired ceramics was evaluated by scanning electron microscopy. The results indicated that the nepheline-syenite improved the evaluated properties of the clay and attended the specifications of vitrified ceramic tiles.

Jan 1, 2010

By R. H. Seraphim

"Western Mines Limited produces gold, silver, copper, lead and zinc from a number of Paleozoic volcanogenic deposits near Buttle Lake on Vancouver Island. The deposits were emplaced along a series of submarine linear volcanic ridges that extended for at least 6,000 metres in a northwesterly direction.Rock types mapped include: andesitic, dacitic and rhyolitic flow s and volcanic breccias; detrital breccias, tuffs and hematitic silts; black and green cherts; and a variety of dykes and sills, including quartz porphyry and diorite. Orebodies are associated invariably, and in places intimately, with quartzsericite schist and rhyolitic rocks. The ore is complex, varying in mineralogy and tenor both within each deposit and from one deposit to another.Recent studies have increased our knowledge of the structure and left no doubt that the orebodies were deposited both within the throats of the linear vents and on paleoslopes adjacent to these vents.IntroductionWestern Mines Limited operates an 850-tonne-per-day mine, located 85 km south of Campbell River, B.C. The mine is at approximately 400 metres elevation, near the south end of Buttle Lake on Vancouver Island (Fig . I). It has operated since early 1967 and produced 3,650,000 tonnes with an average grade of 1.9 g (0.06 oz) gold, 93 g (3.0 oz) silver, 1.6 per cent copper, 1.0 per cent lead and 7.5 per cent zinc per tonne by the end of 1978. Current reserves are 1,157,000 tonnes of 2.7 g (0.09 oz) gold, 117 g (3 .8 oz) silver , 1.2 per cent copper, 1.2 per cent lead and 8.0 percent zinc per tonne (December 31, 1978).Ore from one zone, known as Myra High-Grade, is mined and milled separately because of its grade. Ore milled prior to December 31,1978, plus reserves, 180,715 tonnes of6.6 g (0.21 oz) gold, 554.5 g (17 .7 oz) silver, 0 .8 per cent copper, 3.2 per cent lead and 10.6 per cent zinc are included in the figures listed in the preceding paragraphs."

Jan 1, 1980

THE successful establishment of iron blast-furnace plants at Newcastle and Lithgow naturally invites attention to the economic utilization of the various products and by-products arising out of the industry.The general similarity in composition between Portland cement and iron blast-furnace slag very early attracted attention both in, the cement and iron-smelting industries. Probably the first use made of blast-furnace slag in the cementindustry was not of an honourable nature-viz, to use an almost worthless and cumbersome by-product as a not readily detectable adulterant in Portland cement, which was at that time very costly to manufacture.The astonishing discovery was made that in many cases the adulterated cement was stronger than the original unadulterated article. It was found that chilled blast-furnace slag introduced in moderate quantity and finely ground with the cement clinkerdid not injure, but usually improved, the quality of the resulting cement. This mode of, manufacture is recognized, especially in Germany, as a legitimate branch of the cement making industry.The use of slag for the manufacture of both slag cement and Portland cement has assumed very large proportions heth in USA and Europe so much so that in the former country plants not well situated and equipped for cheaply making cement from clay and limestone are being forced to close down. Slags from other than iron blast-furnaces, together with some of the latter, are not suitable for cement-making. All slags which disintegrate and fall into powder are wholly unfitted for cementmaking.Those highly charged with mineral oxide compounds...

Jan 1, 1918

By Manqiu Xu, Songtao Yang, Zongfu Dai, Robert Pelton, Carla Abarca

"Fine mineral particles are difficult to process by flotation because of their low collision efficiencies with air bubbles. Decreasing air bubble size and increasing mineral particle size through flocculation are the most common approaches to improve flotation efficiencies. Herein we demonstrate that nanoparticle flotation collectors can be engineered to selectively induce fine mineral particle aggregation and promote flotation.Flotation tests of clean fine pentlandite (Pn) and Clarabelle Mill (CBM) rock tails and pyrrhotite (Po) tails that contained significant amount of fine pentlandite have confirmed that the nanoparticles can serve as both collectors and selective flocculants for fine pentlandite. In the case of clean fine Pn, the nanoparticle collectors virtually can float almost all Pn fines. Scoping tests on CBM tails have shown significant improvement in nickel recovery. Addition of nanoparticles as a flotation aid can recover 20% of the nickel contained in the rock tails and 40% of the Pn contained in the Po tails compared to current mill operations giving 0% nickel recovery from rock tails and no Pn selectivity from Po tails. Ongoing work includes attempts to identify optimal strategies for employing nanoparticles in fines flotation.IntroductionFine particle flotation is an industry-wide challenge in mineral processing. Fine mineral particles are difficult to process by flotation because fine particles have low mass and thus low momentum, which results in their low collision efficiency with air bubbles (Dai, Fornasiero, & Ralston, 1999). In addition, fine particles have not only high specific surface area but also more active surface area, which causes high reagent consumption. For base metal sulphide minerals, particle size between 10 µm and 70 µm is a typical range where high flotation recoveries can be achieved with conventional flotation chemistry and acceptable cell residence times. For pentlandite, the flotation recoveries decrease sharply when the particle size is below 10 µm and hydraulic entrainment is the dominant mechanism, giving recoveries proportional to water recovery and no Pn enrichment. (Jameson, Nguyen, & Ata, 2007)"

Jan 1, 2015

By John Brennan

OK, I’ll admit it: I’ve always been a big Monty Atwater fan. Not only is the man credited with being the father of modern avalanche forecasting and safety in the United States, but he is also responsible for developing the avalauncher. Through its more than 40-year history, the avalauncher has gone through many changes yet continues to prove its worth in avalanche mitigation work.

Jan 1, 2007

The following is a summary of some of the companies that were exhibiting their products and services at MINExpo INTERNATIONAL 2000. Atlas Copco develops, manufactures and markets rock drilling tools, tunneling and mining equipment, and surface and geotechnical drilling equipment. The company provides a line of drilling products, including production drilling rigs, rock reinforcement bolts and rock drills. Atlas Copco’s Boomer is a series of high-capacity drill rigs that provides economy, production capacity and reliability

Jan 1, 2000

By William R. Yernberg

In October 1999, Liebherr-America, Liebherr Construction and Liebherr Mining Equipment held anopen house at its Newport News, VA, plant. The open house was held to celebrate the company’s50th anniversary and to demonstrate the new TI 272mining truck. Attending the open house members of the media, vendors and company representatives from all over the world. In his introductory comments, company president Peter Eller announced Liebherr’s dedication to expanding its presence in North America. Liebherr now has 30 dealers across the United States. As part of the open house, a brief history of Liebherr was presented, beginning with its creation in1949. Liebherr engineering and sales representatives were available to answer questions.

Jan 1, 2000

Small scale gold mining operations in Papua New Guinea (PNG) have been observed to use very low flow rates of water in sluice boxes. In a series of laboratory experiments carried out to determine whether this approach was unsatisfactory or not for their situation, indications were obtained that it had some advantages in the recovery of fine gold but at the cost of considerable throughput. The separation mechanisms operating in such a system are analysed.

Jan 1, 1986

By Giannini M

Of the optimization techniques proposed in determining the optimum open pit limits, dynamic programming and graph theory have proved most successful. However, publications on these two methods lack a certain amount of rigour and clarity in exposition. Certain ideas in the methods have been clarified and additional features introduced in order to make them more sensitive to practical applications. A case study in the form of an application of these ideas on data from a producing mine is presented and discussed.

Jan 1, 1986

By Bill Kyslinger

In underground mining, machine design is predominantly dictated by mine conditions and individual customer desires. In partnership with Boart Longyear Poland and KGHM, J. H. Fletcher & Company was tasked to design and manufacture a single-boom, single operator drill module for installation of 1.2 meter expansion bolt in a 1.6 meter height mine. The objective was to produce a machine to provide ergonomic improvements for the operator while working in the mine environment. This dictated the requirement for a small easily controlled, maintenance friendly design with a remote operator?s control station. The selected design method was to use starter and finisher drill steels. This combination, requiring a number of mechanized machine motions, provides the ability to drill the required depth in the specified mine height. To accomplish the task from a remote location, a conscious decision was made to employ current technology in the form of small pressure compensated hydraulics and electronic controls. The result of the design method is a modular assembly with each sub-component designed to be replaceable and adjustable independently from other machine components. The low profile remote roof bolting module is made up of six major sub-components. Each major component is painted a different color to help the operator make the visual connection from the drill module to the operator?s control/display monitor. The Stabilizer (White) secures the module between the mine top and floor. The Drillhead (Orange) produces the drilling rotation and torque but also must slide out of position to allow the machine to manipulate the drill consumables. The Drill Steel Carousel (Blue) holds and indexes the starter and finisher steel from position to position. The Manipulator Arm (Green) moves and guides the drill steels and drill consumables from position to position during installation. The Roof Reference Guide (Yellow) locates the mine roof and guides the drill steels and drill consumables into position. The Linear Bolt Carousel (Purple) holds the drill consumables. The low profile remote roof bolting module allows the operator to drill and install a roof bolt manually or automatically with the push of a button. This design substantially reduces the operator?s exposure in the mine environment, as well as inherent pinch points and rotary hazards. Positioning the operator safely in the confines of the air conditioned cab.

Jan 1, 2006

The Archaeozoic Willyama Complex at Broken Hill has suffered several periods of deformation and metamorphism. New structural and petrological information together with that available from the literature gives a picture of the metamorphic evolution of the Barrier Ranges. Several epochs of metamorphism are recognized, and potassium-argon dating of minerals has been applied with limited success to the resolution of these epochs.INTRODUCTIONAdvancements in the mineral industry at Broken Hill over the past eighty years have been accompanied by a continual striving towards increased understanding of both the geological history of the Barrier Ranges and the environment of the Broken Hill ore deposits. However, although many detailed studies of selected localities and particular-aspects of Broken Hill geology have been carried out recently, the regional geology of the Barrier Ranges as a whole has received little attention from a petrological viewpoint since the pioneer investigations of Mawson (1912) and Browne (1922). There still remains a great need for regional surveys combining field studies of the habits, structures and outcrop relationships of the various rock types with laboratory investigations of their chemistry, mineralogy and microscopic ,fabrics. Recording observations arising from three brief visits to the Broken Hill area during 1959 and 1963 may stimulate further surveys.During one of these visits, the generosity of the Zinc Corporation Limited in providing field transport and geological guidance enabled the writer to collect material and study field relationships and appearance of the various rock types at numerous localities covering most of the Willyama outcrop. A complete study has not been conducted...

Jan 1, 1963

By Grainne A. Matthews

Jan 1, 2009

By Yates C, Gillie E. W, Finucane K. J

During the year 1940 a complete investigation was made of the whole of the stoping operations throughout the Great Boulder Mine and, as a result, it was decided to convert some of the existing shrinkage stopes into cut-and-fill stopes, and also to mine many of the more recently developed ore blocks by the latter method. The necessity for filling was due primarily to the structure of the ore blocks, the character of the walls and possible excessive dilution, but was influenced also by the grade of the ore-block and by the fact that cleaner mining can be carried out by cut-and-fill stoping.The comparatively few cut-and-fill stopes in operation prior to 1940 had been filled mainly with waste rock from development work, but as the amount of this material available, or likely to become available, would have been wholly inadequate for future operations, it was proposed to construct a system of passes to supply filling material from the surface.Owing to the distribution of the stopes, no central pass or system of passes could be devised which would service all the stopes satisfactorily.However, work was commenced on two passes, one designed to service the cut-and-fill stopes in the Eastern Section of the mine, and another to service those in the Western Section. It was realised that these passes could serve only a small proportion of the total number of Stopes (Figs. 1 and 2). During the progress of this work experiments were undertaken to test the possibility of using filtered tailings underground as an adjunct to the above scheme, but for various reasons these were only partially completed.Early in 1942 it was suggested by the Mill Superintendent that an attempt be made to fill with wet classified flotation tailings as practised at Mt. Lyell in Tasmania and at the Triton Mine at Reedy, West Australia. For the purpose of testing this, an experimental stope was prepared on the 309-ft. level, "X" Lode. This was 100 feet long and averaged 4 feet in width. Water-tight rearings were built at each end of the stope and waste rock fill was spread to a height of 6 to 8 feet above the timber. Used filter cloths were laid on top of the fill and brought a few feet, up the walls of the stope. A two-inch victaulic drainage line was then placed in position, the end passing through a hole in one of the bearings and thence to a sump. In the central portion of the stope two vertical pipes were brought up from this line. These were bored with one-inch holes staggered on opposite sides of the pipe, the vertical interval between each hole being one inch. The holes were then stopped with...

Jan 1, 1945

The area around Big Bell was actively explored and sporadically mined for gold from 1904 onwards. The lease was named Big Bell in 1913. The property became established as a major mining centre with the development of the Big Bell underground mine in 1936. Mining operations commenced in late 1937 and ceased in January 1955, after milling 5.56 million tonnes of ore and producing nearly 21 tonnes of gold. In 1969 Australian Consolidated Minerals Ltd (A.C.M.) acquired the deposit then explored it alone and in joint venture until the current joint venture agreement with a subsidiary of Placer Pacific Limited (PPL) was negotiated in 1984. Following exploration and evaluation of near surface mineralisation, and a reassessment of the remnant pillars underground, the concept of a large open pit in conjunction with an underground mine evolved. The feasibility study was completed in October 1987, and the decision to go ahead was formally announced on 2nd December 1987. Placer Dome Technical Services Ltd were contracted to be the Project Managers, commencing construction on site early in January 1988 and handing the plant over to the operators 13 months later. The capital cost of the project at handover was estimated to be $133 million. The operating team commenced pre-production stripping of the open pit on 1st May 1988. By 31st January 1989 almost 16.0 million tonnes had been stripped and 350,000 tonnes of ore stockpiled.

Jan 1, 1989

By H. K. Lin

Deepwater discharges of sulfide flotation tailings have been practiced for several decades. Oxygen penetration and organic matter content in such environments are the two major factors that determine their reduction-oxidation condition and hence the rate of sulfide mineral dissolution under such discharge environments. In this study, the effects of solution redox potential and pH on the dissolution of some heavy metals from sulfide flotation tailings were examined. Zn, Pb and Cu concentrations in solution were all higher at a higher redox potential and lower pH. Dissolved Zn concentrations reached 100 ppm even at a low redox potential of 105 mV and near neutral pH after 33 days. Pb concentrations were below 2 ppm at 105 mV and near neutral pH after 165 days. At 105 mV, the Cu concentrations were below 0.2 ppm at near neutral pH after 165 days. At pH 2.3, the Fe concentrations were higher at 420 mV than at 105 mV. But at pH 6.8, the Fe concentrations were lower at 420 mV than at 105 mV, due to the oxidation of Fe2+ to Fe3+ and the subsequent precipitation of ferric hydroxide. Arsenic concentrations in solution were all less than 0.002 ppm. For Zn, Cu and Fe, no significant differences were observed between the tests in solutions prepared using seawater and those using distilled water. However, Pb concentrations reached higher levels in solutions prepared using seawater.

Jan 1, 2009