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By Shuan-cheng Gu

Roof bed separation often occurred due to the deformation incoordination of surrounding rock following the excavation of mine roadway. Bed separation has effect on the bolts, and the estimation of the influence will directly affect the safety of support systems. In this paper, the hyperbolic function model to analyze the load transfer mechanism on the bolts was simplified as the exponential function form for easy calculation. An elastic-plastic analysis model of the bolt loading occurred by the bed separation was established. And the development low that the bed separation affected to the bolt loading was discussed. According to the parameters analysis of different separation values and locations, the influence law of the bolt loading caused by roof bed separation was summarized. Finally, the effects of bed separation were considered for the bolting design, it was able to provide a reference to the anchorage design of stratified rock.

Aug 1, 2013

By R. L. Bishops

This paper discusses some of the materials, processes and systems used in motor insulation. Among the materials mentioned are epoxies, polyesters, mica paper composites and wire enamels. Two processes developed to take advantage of the special characteristics of two of these materials are described, and how these materials are used in several new insulation systems now on the market is discussed. Finally, future trends in motor insulation are outlined.

Jan 1, 1969

By Zhan Zhang, Hiromi Nagaumi, Zhen Li

"Recently, the remarkable strengthening effect of ??-Al(Mn, Fe) Si dispersoids at both ambient temperature and elevated temperature were found by several researches. A large amount of dispersoids can be formed by applying special heat treatments and within a suitable range of chemical composition of AA3xxx alloys. In the present work, the influences of Cr addition on the mechanical properties and microstructures of the Al-Mn-Mg-Si alloys were investigated. The mechanical properties at ambient and elevated temperatures were evaluated by micro-hardness and yield strength. Moreover, the microstructures in as-cast and heat-treated conditions were quantitatively analyzed by optical and electron microscopes. Results revealed that Cr also had effect on the number density and volume fraction of dispersoids. Micro-hardness and yield strength at ambient temperature increased with the increasing content of Cr, and the Cr addition increased the yield strength at elevated temperature as well. Moreover, the creep resistance at 300°C improved dramatically with the increasing content of Cr.INTRODUCTION Traditionally, AA3xxx aluminum alloys were widely used in packaging, automobile and architecture industries, because of its good formability, excellent corrosion resistance and weldability. And AA3xxx alloys were considered as non-heat-treatable alloys. However, the strengthening effect of dispersoids in AA3xxx alloys was discovered recently (Li & Arnberg, 2003;Li, Muggerud, Olsen, & Furu, 2012; Li, Zhang, & Chen, 2016; Liu & Chen, 2015).Alarge amount of dispersoids could precipitate by a proper heat treatment.In order to further improve AA3xxxalloys, the composition of the alloys should be optimized. A few previous studies were reported to investigate the influence of compositions on AA3xxx alloys. Adding Mn element could enhance the precipitation of ??-Al(Mn, Fe)Si dispersoids and improve the yield strength(Muggerud, Mørtsell, Li, & Holmestad, 2013), as long as the concentration of Mn was under the solid solution limit. Fe decreased the solubility of Mn and accelerated the precipitation rate of ??-Al(Mn, Fe)Sidispersoids(Li & Arnberg, 2003), the yield strength and creep resistance at elevated temperature could increase with an optimized content of Fe(Liu & Chen, 2016). Mg element would affect the nucleation process of ??-Al(Mn, Fe)Sidispersoids by forming metastable Mg2Si(Hirasawa, 1975; Li, Zhang, & Chen, 2017a; Lodgaard & Ryum, 2000), metastable Mg2Si precipitated during heating process and promoted the precipitation of ??-Al(Mn, Fe)Sidispersoids, moreover, Mg provided solid solution strength for AA3004 alloys(Li et al., 2016). Si increased the volume fractionof ??-Al(Mn, Fe)Sidispersoids(Muggerud et al., 2013)and decreased the size of ??-Al(Mn, Fe)Sidispersoids(Li, Zhang, & Chen, 2017b). With the addition of Mo, the size of dispersoids became finer with a higher volume fraction, the volume percentage of dispersoid free zones was reduced. Elevated temperature yield strength and creep resistance improved due to Mo addition (Liu, Ma, & Chen, 2017).However, the effect of Crelements on microstructure and mechanical properties of AA3xxx alloys were rarely reported."

Jan 1, 2018

By PAULL. BROUGHTON

Commercial deposits of sodium sulphate are harvested from alkaline lakes that are widespread throughout semi-arid southern Saskatchewan and adjacent southeastern A lberta. Concentration of sodium sulphate occurs in undrained basins under semi-arid conditions. Precipitation runoff from land adjacen1 to 1hese basins leaches 1he mineral from the soils and carries it in solu1ion 10 the basins. The process may be largely subsurface, wherein spring seeps feed basins associated with buried (preg/acial) river valleys. Evapora1ion during summer concentrates salts in the brines, and chilling of water below sa/Uration poin1 during win1er resu//s in deposi1ion of sodium sulpha1e (mirabili1e) crystals on lake bo//oms. Sodium su/pha1e, commercially known as sa/1 cake, ranks second only 10 po1ash in cen1ral-wes1ern Canada's nonme1allic mineral production. // is recovered from su,face brines, directly from intermittenl salt beds, and, until recently, by solution mining of shallow subswface deposits. Sodium sulphate is extrac1ed from seven alkaline lakes and sail f/a1s in Saska1chewan and one in Alberta. Annual produc1ion is approxima1e/y a halfmillion tonnes. Manufacture of kraft paper is the mos1 significanl marke1 for salt cake, but addi1ional quantifies are used in the glass and detergent manufac1uring indus1ries.

Jan 1, 1984

By J. B. Boniwell

The INPUT electromagnetic prospecting system was originally developed by Dr. A. R. Barringer in an effort to increase the sensitivity and penetration of airborne EM methods. Although brought to an operational state some several years ago, it is only through relatively re-cent modifications and testing that some of the potential of the system has been fully realised. This is brought into perspective by some recent results over known ore deposits and geologic environments.

Jan 1, 1967

By J. N. Van der Merwe, M. Mathey

"We present an analysis of the mechanical properties of coal specimens from various coalfields and seams in South Africa. Our database comprises of 1800 test results from uniaxial and triaxial compression tests, as well as indirect tensile strength tests, which we collected from the various mining houses and research agencies in the country. We inspected the database for possible errors and present a brief description of the verification procedure in the paper.In the analysis, we reveal that the collected samples of strength and elastic properties of South African coals can be represented by single lognormal or normal distributions with only few outliers. This finding indicates that the samples realistically approximate the population of mechanical coal properties in the country and may suggest that the properties are randomly distributed. Significant coalfield- or seamspecific trends for the mechanical properties of coal are not clearly discernible from our data.Typical coefficients of variation for the individual mechanical properties range between 25-50 % on a country-wide and seam-specific level of analysis. Average uniaxial compressive strength values, however, are closely clustered for all seams. A comparison with data available from international coal strength studies show the distinct difference between South African coals and seams in countries of the Northern Hemisphere, where differences in the average coal seam strength are more pronounced.We observe that the number of specimens whose failure mode is influenced by the presence of natural discontinuities reduces drastically with the application of very small confining pressures to the specimens. Further, the strength-reducing influence of discontinuities diminishes with increasing confining pressures."

Jan 1, 2015

By John O. Galloway

"The year 1947 was a momentous one in the history of the petroleum industry in Canada. It was in that year that Imperial Oil Limited made its discovery at Leduc, the forerunner of other discoveries, large and small, and the spark wl1ich started a most intensive exploration and development programme there.If, to use boxing parlance, Leduc was the first blow of a one-two combination which left doubting Thomases groggy, then Redwater was the number two blow which achieved the knockout. The oil industry's exploration leaders did about-face without delay and the rush of oil operators of all classifications to western Canada began. It is still continuing, and the influx of capital which the operators have brought in and are bringing in has a bouyant effect upon the over-all economy. The boom is on, but it is a sound one, and it is difficult to conceive that it will have anything but the most beneficial effect on Canada, and particularly western Canada.The petroleum industry is an important segment of the general economy. Its activities call for tremendous amounts of capital; its employees are well paid; it is a large customer for a wide range of products of other industries; its commodities are essential to the citizens and the nation.The industry is carried on by highly aggressive and independent groups and individuals, of which a small minority are integrated while the majority are relatively small operators engaged in only one or two phases of the business. Competition is the rule and, since the nature of the business is mass production, the industry is faced from time to time with serious problems, many of which are peculiar to it."

Jan 1, 1950

By Tony Szwilski

Using Unity 3D as a collaborative multi-user virtual on-line environment, an interactive virtual underground mine platform (IVUMP) is being developed to provide on-line access to mine safety preparedness training with a focus on mine emergency response exercises (MEREs). Communication and information flow among MERE participants and their actions can be monitored, recorded and evaluated. A mine ventilation simulation utility VFIRE is being incorporated to enhance the realism and interactive nature of the ?in-world? exercises as well as extend its functionality to include training in real-time ventilation and fire control.

Aug 1, 2013

By Minoru Fujita, Ian M. Johnson

"A helicopter-borne geophysical survey was flown in 1978 over selected areas on Kyushu Island, Japan. The principal sensors were a moving source electro-magnetic system and a magnetometer. Maps of apparent resistivity were generated from the EM data. Based on the resistivity signature of known deposits within the survey areas, targets were selected for ground follow-up. Drilling of one such target in late 1980 resulted in the discovery of a gold deposit from which full production will begin in the summer of 1985. The deposit contains a minimum 120 tonnes (3.86 million ounces) of recoverable gold and is the largest in Japanese history. The deposit is in a geological setting previously unsuspected of hosting precious metal deposits. The case history suggests a preferred exploration strategy which might be employed in other similar geological environments.IntroductionThe Hishikari area is located some forty-five kilometres north of Kagoshima city, Kagoshima Prefecture, Kyushu Island, Japan (Fig. I). The area and its environs is one with a number of gold deposits which have been worked with varying results since the late 1800s. The large st deposit in terms of recovered gold is the Ohkuchi (or Oguchi) Mine (Fig . 2) which was recently closed due to exhaustion of reserves. The Ohkuchi Mine started production in 1896. A total of 22.2 tonnes (714 ,000 ounces) of gold, with an average ore grade of 13.6 grams/tonne (0.39 ounces/ton), was extracted over the Life of the mine.In an attempt to discover new deposits , the Metal Mining Agency of Japan (MMAJ) carried out a regional geologic mapping program of the area between 1975 and 1977. This was followed by a helicopter-borne electromagnetic and magnetic survey. The airborne survey was flown by Scintrex and the compiled results presented to MMAJ in early 1979."

Jan 1, 1985

By F. Kitzinger

Electromagnetic testing of wire rope has become more and more reliable over the past two decades. This improvement is partly a result of an unprecedented progress of electronic technology, which permitted the development of a new breed of testing instruments. There are two basic methods for the electromagnetic testing of wire ropes, the AC method and the DC method. Both methods rely on magnetic field disturbance caused by mechanical anomalies in the rope structure. The wire rope under test is passed through a magnetic excitation field, which can be a weak alternating field or a strong static field. Because the alternating field is produced by an alternating current, these instruments are of the AC type(l). In the early days of ND-testing, strong permanent magnets were not yet available; therefore, the static magnetic field was produced electromagnetically with direct current. Instruments based on static excitation are still called DC instruments(2), even though the field is now produced by a permanent magnet. Both these methods have certain characteristic features. The AC method can detect loss of metallic area caused by corrosion or other effects, whereas localized faults such as broken wires are better detected by the DC instruments . The basic principles of the wire rope testers have remained unchanged over the years and the improvements present in the new instruments usually reside in the signal processing and recording sections. The Instrumentation Department of the Noranda Research Centre* has been involved in a four-year development program which resulted in a new type of wire rope tester, the Magnographv** . This new instrument in many ways represents a considerable departure from the traditional wire rope testers. The Magnograph has already been patented in Canada and the U.S.A.(3), and patent applications are pending in other countries.

Jan 1, 1979

By T. T. Wang, T. H. Huang, S. S. Zhan

"Fractures with diverse features dominate the hydraulic behavior of fractured rocks and are one of the major subjects for hydrogeological characterization of a site. This study investigates curve patterns obtained by packed tests, and as well the influence of fracture features based on 59 sets of in situ packer tests with different fracture combinations and fracture features. The result shows that, in the example of Heshe site, neat and tidy fractures usually provide stable channel for water flow during testing, and the hydraulic properties of fractures infilled with breccia and mud may change during testing because of leaching and/or washed out of infilling breccia and mud. Different combinations of fractures with diverse features in packed test sections lead to different curve patterns for in situ hydrogeological tests. For groundwater flowing predominately through neat and tidy fractures, the pressure-discharge curve of modified Lugeon tests are usually linear curve pattern, and the pressure decrease while the discharge increase in pressure-discharge-time curves of single-hole double packer tests, which benefit statistically determining the transmissivity of dominant fracture sets. INTRODUCTIONFractures interlaced in rock masses are major channels for groundwater flow and generally account for the anisotropic and heterogeneous characteristics of permeability for fracture rocks. To describe reasonably the permeability of a fracture rock, the Discrete Fracture Network (DFN) approach and others with similar ideals have been developed. Many methodologies and associate equipment, for instance, the televiewer and the in situ hydrogeological test, have been proposed to investigate the spatial distribution and the transmissivity for different fracture sets, which are two main parameters necessary for the DFN or similar model simulation (Pearson & Money, 1977; Barker & Black, 1983; Hsieh et al., 1985; Bernard et al., 2006; Quinn et al., 2012). However, diverse outlooks for the pressure-discharge curves and the temporal pressure and associate temporal discharge curves often confuse the investigation results by significant deviations on derived permeability (Houlsby, 1976; Zlotnik, 1994; Royle, 2009; Camilo, 2010).Aiming on technical development for in situ hydrogeological tests and fracture investigation, an experimental well site with 10 wells has been established in Heshe in central Taiwan since 2011 (Wang et al., 2011; Song, 2012; Zhan et al., 2013). Extensive geological survey and well-hole scanning by a televiewer provide spatial distributions and outlooks of fractures in detail. Additionally, a series of Lugeon tests, double packer injection tests and pumping tests have been performed to investigate the permeability of fracture rocks, and dominate fracture sets as well. Based on the results obtained from the Heshe site, this study classifies the curve patterns of hydraulic packer tests. The features of fractures involved in packed sections for packer tests are then inspected in detail. Relationship between the curve patterns of hydraulic packer tests and associated features of corresponding fractures in rock are discussed and addressed accordingly."

Jan 1, 2015

By J. G. Kim, B. G. Chae, D. S. Cheon, E. S. Park

The underground structures such as high-level radioactive waste disposal thermal energy storage should be designed and constructed considering thermal-mechanical characterization because of long term and/or cyclic thermal stress. High temperature changes in these structures can extend the existing cracks and generate new cracks in surrounding rock mass. In case of long term and/or cyclic thermal stress conditions, it is possible to lose the function of structures caused by the significant cracks and fracture growth in the rock mass. In this study, the critical thermal crack temperature of the granite, limestone and thermal Kaiser effect were evaluated. Experiments were carried out with the heating speed of 1.5?/min. To avoid thermal shock and target temperatures were set at 150? and 250?. In order to verify the thermal Kaiser effect, the samples were heated by 150 ? after 2-3 repetition to 250?. The generation and growth of cracks were observed through an acoustic emission measuring system. The variation of the physical rock properties was measured before and after thermal experiments. After compared with the thermal experiments using PFC2D, numerical simulations were carried out at higher temperatures (400?). The experiments showed that the initial thermal crack temperature of granite and limestone is about 35?, 32? and the critical thermal crack temperature were about 69? , and 49? , respectively. The experiments confirmed the thermal Kaiser effect of experimented granite and limestone due to thermal cyclic loading. From the numerical analysis, the critical crack temperature showed the same tendency as the thermal experiments. The P and S wave velocity of the sample after the experiment were reduced. Therefore, when heat is applied in long-term and repetitive conditions, these cracks may affect the function and stability of the underground structure. Therefore, further studies of thermal stress effects should be performed.

Jan 1, 2015

By James J. Scott

"In the two years since their introduction, Friction Rock Stabilizershave replaced40 per cent of the previously used fixtures in the metal and non-metal mines in the United States. The Friction Rock Stabilizer, or ""Split Set "" , is a mechanical rock stabilizing system which uses friction to prevent rock movement . The Split Set is a tapered, rolled, steel tube that is slotted along its length. As it is driven into a drilled hole smaller than its diameter, it compresses, pre-loading the surrounding rock. This paper discusses the uses and acceptance of the friction rock stabilizer in mines in the United States. IntroductionFriction Rock Stabilizers, commonly called Split Set™· Stabilizers, have been under development by the author and Ingersoll-Rand Company since early 1973. Five years of intensive laboratory and field testing led to their introduction to the metal mines in the United States in the fall of 1976. Actual sales started in February of 1977and, to date, over five million units have been marketed to metal mines. The present rate of usage is near 3 V2 million units per year, which is approximately 50070 of all roof fixtures used in the United States metal mining industry,Richard Hoppe, senior editor of Engineering & Mining Journal. , in an article in the February 1979 issue entitled ""Winning the Battle Against Bad Ground"", said: ""In hardrock mining operations in the western U.S., particularly underground uranium mines where exceedingly difficult ground is common, no roof support system has been accepted more quickly than the Split Set friction bolt invented by Dr. James J . Scott and developed by Ingersoll-Rand Co."" This paper describes how Friction Rock Stabilizers function and presents technical data to show the uniqueness of such systems."

Jan 1, 1980

By W. A. Plachner, Schiller E. A., S. P. Santiago

"The Monkman Coal Property is located in the Northeast Coal Block of British Columbia. It is divided into the Duke Mountain Block on the north east and the Dip Slope on the west. Together, these areas cover 39,503 ha of coal licences.The property is underlain by Jurassic and Lower Cretaceous marine and continental sedimentary rocks. Economic coal measures are contained within the Gates Formation. Exploration of the property began in the early I970s, with drilling commencing in 1975. To date, 255 holes have been drilled and nine adits have been driven to recover unoxidized coal samples.The property has a geological resource potential of 2.8 billion tonnes of medium and high-volatile bituminous coal. Medium-volatile bituminous reserves, totalling 68.9 million ROM tonnes at an over-all strip ratio of 6.3:1, have been identified in three pit areas in the Duke Mountain Block.Construction start-up will commence when sales contracts are arranged. The clean coal will be exported via the Ridley Island Terminal at Prince Rupert.IntroductionThe Monkman Coal Property is located in the Northeast Coal Block of British Columbia in the southern port ion of the Peace River Coalfield. The coal field encompasses a strike length of 250 km of Lower Cretaceous coal-bearing strata in which 13 companies have identified several billion tonnes of resources and several hundred million tonnes of reserves. Currently, two companies with contracts are in the construction phase, and are scheduled to produce coal by early 1984. Quintette Coal Ltd. has a contract with Japanese steel mills to supply annually 5.0 million tonnes of metallurgical and 1.5 million tonnes of thermal coal. Teck Corporation (Bullmoose property) has a contract to supply 1.7 million tonnes of metallurgical coal annually."

Jan 1, 1983

By N. Dobrin, R. Sheinman, Y. V. Kokotov, L. N. Braginsky

Increasing the production of a Mixer-Settler unit requires either increasing flow rates or increasing extractant concentration. The mixers still have to ensure complete emulsification and to maintain high values of specific interface surface area in order to provide a high rate of mass transfer. Theoretically, an increase in mixing intensity can support increased flow rates without reducing extraction efficiency. Unfortunately, conventional pump mixers and mixing systems create small droplets that do not separate easily. As pumping action and mixing intensities are increased, the quantity of small droplets increases. We describe the development and industrial application of a novel mixing system for efficient mass transfer without forming significant quantities of small droplets, targeting both high mass transfer rate and low entrainment values.

Jan 1, 2014

By Don McColman

"Tires, although not always the largest single cost item in open-pit mining operations, will place in the top three, along with explosives and fuel. How this high-cost supply is controlled is dependent upon on an efficient tire program. The success of this program is, in turn, dependent upon the people who are directly associated with tires and their use, namely: the mine's tire personnel, the tire sales representatives and a technician for the rubber company. The technician will relay his observations and information received from the mine personnel back to the manufacturer with recommendations to overcome current problems .Haulage truck tire life and costs in a hard rock open-pit mine are governed and controlled by four important factors:I) Field control.2) Operating within manufacturer's guidelines.3) Different tire purchasing methods.4) Scrap piles.Field ControlPerhaps the most influential people involved in this program are those who live with the tire through every hour of its lifespan: the truck driver, the shovel operator, the dozer operator, the grader operator and the shift boss. Of these, the truck driver has the most control, in that he can drive over or around rock s as these situations arise. The loading area, the edge of the haul road and the dump account for most of the tire injuries.This is why shovel, dozer and grader operators must appreciate their influence on haulage tire life. Spillage cleanup must be ongoing and is not being done adequately if any of these operators are idle. The shift boss that drives by a rock on the road without removing it or calling for a cleanup has little recourse with the truck driver who runs over it-he has sanctioned the driver's actions by his own neglect."

Jan 1, 1986

By Todd S. Harris

"IntroductionThe western region of North America has long been considered a dynamic market supporting such diversified industries as lumber, agriculture, cement, and electronics. In recent years however, the region has also been the focus of a great deal of activity in the extender and filler mineral s business from companies seeking to position themselves to take advantage of the large demand for these materials both here and abroad.Extender and Filler MineralsExtender and filler mineral s include 15different products used in numerous end uses. The nine most important extenders and fillers are listed in Table I. These products range in price from under $50 a ton to over $4,000 a ton and basically represent the following three different types of minerals:Particulate products-Calcium carbonate; Kaolin; Silica.Platy minerals-Talc (Montana, Canada); Mica.Fibrous minerals-Talc (California, Eastern U.S .A.);Wollastonite.What distinguishes these products from other industrial minerals? For one thing, an important feature of extender and filler minerals is that they are used primarily in such consumer non-durable good s as paper, paint, plastics, sealants, and rubber which traditionally do not react as violently to swings in the economic cycle. In addition, these minerals are sold principally on key physical properties, usually brightness, particle size and shape, oil absorption, and hardness. As part of the physical minerals segment of industrial minerals, extenders and fillers are traditionally the most stable group and typically the most profitable. Studies by C.H. Kline over the past decade on extender and filler minerals has revealed historic average profitability (expressed as a percentage on sales) nearly double that of most other industrial mineral s.The demand for these minerals in the western region (Fig. 1), closely follow s the areas of greatest population concentration. These markets include pulp and paper, mainly in the Pacific Northwest, and paint, around Los Angeles and San Fran cisco. Other significant markets for extender and filler minerals in western North America include joint cements, carpet backing, and plastics, mainly PVC pipe."

Jan 1, 1986

By Douglas H. Silvey

"The historical transformations in fire -resistant conveyor belt compositions in the past 20 years have been influenced by factors of material cost, changing flame and burn test requirements, material replacements, adhesion and oil resistance considerations, increased responsibility and legal liability. Specifically, this has resulted in a swing from neoprene-cotton belts to S.B.R. blends and synthetic fibre carcasses, and tighter quality control and documentation of test data.Flame dynamics are discussed and the function and performance of the multiple types of flame-resistant additives in the flame front are presented. Specific flame and burn test requirements are described. The belt manufacturers' requirements and criteria in selecting the types of flame-resistant additives are presented.The author will describe the composition of the types of flame-resistant compounds used in a practical production, the belts that are available on today's mark et and future developments in requirements that may further transform the composition of fire-resistant belts.IntroductionThe historical transformations of conveyor belt compositions in the past two decades have been based on factors common to those leading to changes in man y organic compositional products. These factors are material cost, new materials, the customer' s changing requirements, government regulation s and increased manufacturer' s liability.As a basis for understanding the product, I will provide a brief breakdown of the conveyor belt composite. Figure 1 represents a cross section of a typical belt. A skim rubber coats each fabric ply of the belt carcass and is of a different rubber composition than the outside layer of rubber which forms the cover. This outside cover layer is designed to protect the belt from environmental factors such as heat, oil and abrasion, and other factors involved in the service condition s under which the belt will operate. In the case of fire-retardant belt s, both the skim coat encapsulating the fabric plies and the outer cover must contain sufficient fire retardancy to overcome the contribution to burning of the decomosition products of the fabric."

Jan 1, 1982

By G. A. Highcock

"Operations started at BCL in December 1973J and the smelter is currently in the seventh year of its fifth campaign. The next major shutdown is scheduled for 1995. During the current campaign, a number of major on-line refurbishments have been carried out without any significant disruption to production. These include the complete rebuild of both drying plant electrostatic precipitators, the installation of a new electrostatic precipitator at the flash furnace, the conversion to a distributed control system throughout the smelter, and the installation of a converter air blowing control system.IntroductionBCL Limited operates a nickel-copper mine in northeastern Botswana approximately 100 km southwest of Francistown. Surface operations for the production of high-grade nickel-copper matte at a design capacity of 42 000 metric tonnes per annum, were commissioned in December 1973. Detailed descriptions of the mine and surface facilities have been presented previously(1-3).Over the years, a number of major engineering modifications and metallurgical projects have been carried out to overcome operating difficulties. improve metal recoveries, increase production rates and provide a better working environment.One of the major results of these projects was an increase in the 19805 in flash furnace feed capacity from 70 t/h to 120 t/h of new concentrate with a nominal feed rate of 105 t/h being achieved.(4)Because of the ore characteristics, i.e. a high mass fraction of ore reporting to concentrate, BCL operates one of the highest capacity spray drying plants and flash smelting furnaces in the world(5).A schematic of the BCL smelter is shown in Figure 1. The smelter is now in the seventh year of its fifth campaign, with the next shutdown scheduled for mid-l99S. In this campaign, the following major projects were completed:"

Jan 1, 1995

By A. Khan, C. Ciriello, W. Oliveira

"The purpose of this paper is to demonstrate the value of Operational Readiness (OR) in the successful delivery of capital projects. OR can be captured using several technical and practical definitions:• To ensure that the capital project being delivered is capable of an effective start up, ramp-up as planned and a sustainable productive operation.• To function as intended when started, with the appropriate people able to run it.• To increase the value in delivering the product/service through established systems, processes and procedures, while simultaneously minimize risk to both the project and the business.Historically, mining and metallurgical capital projects concentrate efforts on cost and scheduling during the implementation and design phases. The completion and subsequent handover of the operational unit is the main objective.When reviewing the mining and metallurgical industry’s capital projects, it seems many poor results and errors in terms of project design and ramp-up are self-inflicted, with the project neglecting to account for key aspects of the future operational plant. Interestingly, if the problems for the future plant occur during project implementation, they can be prevented during the project phase. It is required to connect the operational knowledge with the project in order to ensure an effective start up and operation.The benefits of OR will be shown to be applicable not only to mining capital projects but also to sustaining and business transformation projects. The paper also includes industrial examples showing both proper and improper use of OR techniques.The paper will cover 3 main areas of Operational Readiness: the OR model, OR related risk elements (i.e., risks associated specifically with the improper execution of OR) and conclude with OR specific case studies."

Jan 1, 2016